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1
Xiaoqing, Liu. „Dose-banding studies on oxaliplatin“. Thesis, University of Plymouth, 2016. http://hdl.handle.net/10026.1/8081.
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Oxaliplatin is an anticancer drug widely used in cancer chemotherapy. This thesis evaluates whether a specific dose-banding scheme for oxaliplatin could replace the individual dosing method that is currently used in the oxaliplatin administration. Dose-banding was introduced into UK clinical practice in 2001, as it reduces delays in patients receiving their treatment and, through quality control and end-product testing, safeguards the infusion quality and patient safety. A range of studies were included in this thesis: an extended stability study on oxaliplatin infusions using a sequential temperature cycling design; studies on oxalate, a potential degradation product and metabolite of oxaliplatin which has been linked to oxaliplatin neurotoxicity and the development of an ex vivo pharmacokinetic (PK) simulation model to compare the effect of different oxaliplatin dosing methods on its therapeutic outcomes. The shelf-life of oxaliplatin infusions over a concentration range of 0.2 mg/mL – 0.7 mg/mL is extended to 84 days when stored at 2 – 8℃ plus a further 7 days after being left at room temperature (25℃) for 24 hours. This ensures the unused oxaliplatin infusions are safe to be re-issued to patients, which could reduce drug wastage. The oxalate study suggests that the dose-limiting neurotoxicity of oxaliplatin is unlikely to be directly related to the oxalate produced from oxaliplatin degradation in infusions or from the non-enzymic transformation of oxaliplatin in vivo because the oxalate levels from these routes are minor compared to the endogenous level. The safety and efficacy of dose-banding schemes was demonstrated by comparing the simulated PK characteristics gained from the ex vivo model. Dose-banding with the +10% maximum deviation was selected as the most promising dosing scheme for oxaliplatin. Finally, recommendations are made concerning the introduction of oxaliplatin dose-banding scheme into clinical practice, and on the benefits of harmonised dose-banding schemes.
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Vincent, Jacob Adam. „Sensorimotor Deficits Following Oxaliplatin Chemotherapy“. Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1496136263522854.
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3
Wieczerzak, Krystyna Blanka. „Sensorimotor Analysis of Oxaliplatin Treated Rats“. Wright State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=wright1432856752.
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4
Robinson, Stuart Michael. „The pathogenesis of oxaliplatin induced sinusoidal obstruction syndrome“. Thesis, University of Newcastle upon Tyne, 2013. http://hdl.handle.net/10443/1942.
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Oxaliplatin based chemotherapy has demonstrated remarkable efficacy in down staging colorectal liver metastases such that patients initially considered to have inoperable disease are able to undergo a potentially curative resection. In addition the use of neoadjuvant Oxaliplatin based chemotherapy has been shown to improve progression free survival following liver resection. Taken together this means that ever increasing numbers of patients are presenting for liver resection having received multiple cycles of chemotherapy. Whilst this approach has many advantages the use of pre-operative chemotherapy has been associated with the development of sinusoidal obstruction syndrome (SOS) in the liver parenchyma in up to 40% of patients. It is thought that the presence of SOS significantly increase the risks associated with major liver resection. More recent data also suggests that the presence of SOS within the liver may result in poorer disease specific outcomes in the long term and in particular a higher risk of early intra-hepatic recurrence. At present the pathogenesis of SOS in this context is not understood and no treatment exists to either prevent its development or reverse the histological changes in the liver associated with it. The aim of the current study was to develop a reproducible in vivo experimental model of Oxaliplatin induced SOS and to interrogate this to identify the pathophysiological mechanisms which underpin its development. With this knowledge it was hoped that potential therapeutic strategies could be suggested to ameliorate the development of SOS in patients treated with Oxaliplatin based chemotherapy. C57BL/6J mice treated with weekly intraperitoneal injections of Oxaliplatin and 5- FU/Leucovorin for 5 weeks develop histological changes of SOS when maintained on a iv purified, but not chow, diet. This is associated with increased expression of key matrix remodelling genes within the liver parenchyma such as MMP2, MMP9, TIMP1, TGFβ and Procollagen I. The development of these gene expression changes is accelerated in the presence of tumour within the liver perhaps as a consequence of increased production of inflammatory mediators such as CXCL1. The presence of SOS is associated with a dramatic increase in expression of the serine protease family member PAI-1 which is involved in a variety of processes including matrix remodelling, thrombus formation and cellular senescence. Immunohistochemistry revealed endothelial cells in areas of sinusoidal injury stained positive for the cell cycle inhibitor p21CIP1/WAF1 in keeping with senescence in these cells. This process was associated with depletion of hepatic glutathione and decreased expression of the antioxidant transcription factor NRF2 suggesting a role for oxidative stress in the pathogenesis of SOS. To explore this further the experiment was repeated but this time using dietary supplementation with either the thiol donor N-Acetylcysteine (NAC) or the NRF2 activator butyrated hydroxyanisole (BHA) alongside FOLFOX treatment. Whilst supplementation with NAC had no effect on the development of SOS its development was completely prevented by supplementation with BHA suggesting that NRF2 activating antioxidants may be a useful therapeutic strategy in preventing the development of SOS. In conclusion this study has described the first reproducible experimental model of Oxaliplatin induced SOS which accurately reflects the pathogenesis of the disease in humans. Through interrogation of this it has been possible to identify therapeutic strategies which may be of value in preventing the development of SOS in patients with colorectal liver metastases.
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MONZA, LAURA. „In vitro models for studying oxaliplatin neurotoxic effects“. Doctoral thesis, Università degli Studi di Milano-Bicocca, 2019. http://hdl.handle.net/10281/241333.
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L’oxaliplatino (OHP) è un composto del platino di terza generazione, usato in combinazione con 5-fluorouracile e leucovorin per il trattamento del tumore al colon-retto metastatico. L’assunzione di OHP è in grado di indurre l’insorgenza di due fenomeni di tossicità, acuto e cronico. La tossicità acuta è caratterizzata da disestesie e parestesie transitorie esacerbate dal contatto col freddo. La gravità di questi sintomi è predittiva per lo sviluppo della neuropatia sensoriale cronica.
Sebbene i meccanismi patogenetici alla base della tossicità acuta non siano stati del tutto chiariti, l’ipotesi più accreditata supporta un maggiore coinvolgimento dei canali del sodio voltaggio-dipendenti. Tuttavia, gli studi sino ad ora condotti si sono focalizzati solo su aspetti specifici della risposta elettrofisiologica cellulare ed hanno utilizzato concentrazioni di OHP molto elevate producendo risultati a volte controversi. Per questi motivi, il nostro obiettivo è stato quello di valutare gli effetti di una concentrazione di OHP più fisiologica sulle proprietà elettriche di diversi modelli di neuroni sensoriali. Poiché i neuroni dei gangli della radice dorsale (DRG) rappresentano il principale bersaglio farmacologico dei composti del platino, i nostri studi sono stati condotti incubando con OHP (7.5 μM) cellule F-11 differenziate. Abbiamo quindi studiato le possibili alterazioni prodotte dal farmaco sul potenziale di riposo (Vrest), sulle caratteristiche del potenziale d’azione (AP) e sulle proprietà biofisiche dei canali voltaggio-dipendenti di sodio e potassio. Le loro proprietà elettrofisiologiche sono state studiate con la tecnica del patch-clamp in configurazione whole-cell. Il cisplatino (CDDP 15 μM) è stato usato come composto di controllo per verificare l'esclusività degli effetti indotti da OHP.
Inoltre, al fine di convalidare i risultati raccolti sulle cellule F-11 differenziate, i nostri esperimenti sono stati riprodotti su culture primarie di neuroni sensoriali derivati da DRG di embrioni di ratto o di ratti adulti.
Rispetto alle cellule non trattate, l’incubazione con OHP ha determinato una depolarizzazione del Vrest, una riduzione della frequenza di scarica di AP, un aumento della densità di corrente di sodio e una riduzione della densità di corrente dei canali del potassio ERG. Tuttavia, la somministrazione di OHP non ha avuto alcuna influenza sui canali del potassio delayed-rectifier e sulla durata di AP indotti. Inoltre, OHP ha determinato uno spostamento delle curve di attivazione e di inattivazione delle correnti di sodio TTX-sensibili verso potenziali più negativi ed un aumento della risultante corrente finestra. Un comportamento simile è stato osservato anche per i canali ERG. Al contrario, il trattamento con CDDP non ha determinato variazioni del Vrest ed ha causato una riduzione della frequenza di scarica, un aumentato della durata di PA ed una riduzione della densità di corrente di potassio delayed-rectifier, di ERG e di sodio.
Nelle colture primarie di neuroni sensoriali embrionali, l'incubazione con OHP ha indotto un aumento della frazione di neuroni in grado di generare PA multipli evocati ed un aumento delle densità di corrente di sodio e di potassio.
Infine, i dati raccolti dalle colture primarie di neuroni derivati da ratti adulti hanno mostrato che la somministrazione di OHP per 24 ore aumenta la densità di corrente di sodio, mentre non ha alcun effetto sugli altri parametri studiati.
In conclusione, i nostri risultati hanno messo in luce diversi target di OHP a livello dei neuroni sensoriali, agendo sia sui canali del sodio che del potassio. Inoltre i dati raccolti, suggeriscono che le cellule F-11 differenziate rappresentano un buon modello cellulare per lo sviluppo di strategie farmacologiche volte a prevenire l'insorgenza di neurotossicità causata da un’alterazione della funzionalità dei canali del sodio.Chemotherapy-induced peripheral neurotoxicity is one of the most common and often dose limiting side effects of anticancer drugs. Among others, oxaliplatin (OHP) is a third generation platinum compound used in combination with 5-fluorouracil and leucovorin as an efficient treatment for metastatic colorectal cancer. Unlike other compounds of the same class, oxaliplatin may also cause an acute syndrome characterized by transient cold-induced dysesthesias and paresthesias located at limb extremities and at perioral area. The severity of these symptoms is predictive of the development of chronic and cumulative sensory neuropathy. Hence, unraveling the mechanisms underlying the acute syndrome should not be considered a secondary aim. Since Adelsberger et al. (Eur J Pharmacol 406:25-32, 2000) first described the effects of OHP on voltage-dependent sodium channels, many in vitro studies on different animal models supported the hypothesis of a major involvement of these channels in the acute syndrome. However, all of these works used very high OHP concentrations and focused on single aspects of the overall electrophysiological cellular response to OHP administration and gave controversial results. For these reasons, our aim was to study the effects of an OHP concentration comparable to the one estimated in patients’ blood on the electrical properties of different models of sensory neurons. We thus investigated the possible alterations produced by the drug on membrane resting potential (Vrest), on the main action potential (AP) features and on the biophysical properties of voltage-dependent sodium and potassium channels. Since dorsal root ganglion (DRG) neurons represent the main pharmacological target of platinum compounds, we incubated differentiated F-11 cells (rat DRG neurons x mouse neuroblastoma N18TG-2 cell line) for 24 or 48 h with 7.5 µM OHP. Their electrophysiological properties were investigated by the patch-clamp technique in the whole-cell configuration. Cisplatin (CDDP 15 µM) was used as reference compound to verify the exclusivity of OHP-induced effects. Finally, in order to validate the results collected with the differentiated F-11 cells, our experiments were reproduced on primary sensory neurons deriving from the dissociation of isolated embryonic and adult rat DRGs. Compared to untreated cells, treated F-11 cells displayed depolarized Vrest, decreased firing frequency, increased sodium current density and reduced ERG (ether-à-go-go-related gene) potassium current density. However, OHP administration did not affect the delayed rectifying potassium channels and the duration of induced APs. In TTX-sensitive sodium currents, OHP shifted both steady-state activation and inactivation curves towards more negative potentials and caused an expansion of the window current. A similar shift of both activation and inactivation curves was observed for ERG channels. In contrast, CDDP caused no effect on Vrest, decreased firing frequency, increased AP duration, and reduced sodium, ERG and delayed rectifier potassium current densities. In embryonic primary DRG neuron cultures, OHP incubation induced a significant increase of the fraction of sensory neurons able to generate multiple evoked APs and of voltage-dependent sodium and potassium current densities. Vrest and the firing frequency were not affected by the treatment. Lastly, data collected on primary DRG neuron cultures derived from adult rats showed that administration of OHP for 24h significantly increased sodium current density while no effects were produced on the other parameters of interest. In conclusion, the collected data indicate that OHP has different targets on DRG neurons, acting on both sodium and potassium channels, and suggest that differentiated F-11 cells represent a good cellular model for the development of pharmacological strategies aimed at preventing the onset of neurotoxicity caused by sodium channel dysfunction.
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Cerles, Olivier. „Prévention des neuropathies périphériques induites par les chimiothérapies par une modulation pharmacologique des dérives des formes réactives de l'oxygène et des récepteurs muscariniques“. Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCB106.
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Les chimiothérapies à base de sels de platine exercent leurs effets anti-tumoraux en compromettant l'intégrité de l'ADN. Cette cytotoxicité conduit à une augmentation du stress oxydant qui, à son tour, favorise les processus de mort cellulaire. L'oxaliplatine indiquée dans les cancers métastatiques secondaires du colon et dans les cancers colorectaux, induit une augmentation des espèces réactives de l’oxygène en diminuant le glutathion réduit dans les cellules cancéreuses. Similairement aux autres chimiothérapies à base de sels de platine, elle doit être utilisée avec précaution. En effet, la majorité des patients recevant de l'oxaliplatine développent des neuropathies périphériques. Cette neurodégénérescence est un facteur limitant de cette chimiothérapie puisqu'elle peut nécessiter une réduction du dosage ou même une interruption du traitement si cet effet secondaire atteint une sévérité de grade 3. Les toxicités neurologiques peuvent se manifester dans les heures suivant l'injection sous forme aiguë. La forme chronique résulte d'injections cumulées de doses élevées. La forme aiguë, caractérisée par une paresthésie transitoire et une myotonie, est réversible et se résout généralement en quelques jours tandis que la forme chronique présente une paresthésie et une thermoalgie persistantes résultant de la dégradation axonale distale et de la démyélinisation des fibres nerveuses de gros diamètre. Les voies inflammatoires ont été incriminées dans l'étiologie de cette neurodégénérescence. Le niclosamide, un ténicide modulant les voies Stat3, Wnt, Notch et Beta-caténine, a été étudié in vitro et in vivo. Ayant déjà démontré les propriétés anti-inflammatoires de ce composé dans la sclérodermie systémique, nous avons cherché à déterminer si le niclosamide pourrait également prévenir la neurotoxicité de l'oxaliplatine. Le niclosamide a démontré une neuroprotection à la fois in vitro sur les neurones traités par l'oxaliplatine et in vivo dans les modèles de neuropathies périphériques induites par l'oxaliplatine. Le niclosamide est déjà utilisé en clinique avec des effets secondaires limités. L'association de cette molécule avec l'oxaliplatine pourrait augmenter l'indice thérapeutique de cette chimiothérapie. La benztropine est un inhibiteur des récepteurs muscariniques M1 et M3 possédant un potentiel de remyélinisation démontré dans le système nerveux central en favorisant la différenciation et la prolifération des cellules précurseurs des oligodendrocytes. La répartition différentielle entre les sous-types de récepteurs peut permettre le ciblage spécifique des cellules tumorales, notamment par l'inhibition de la signalisation autocrine de l'acétylcholine. La benztropine est un composé bien toléré qui ne provoque aucune réaction immunologique lors de son administration. Cette molécule présente un effet neuroprotecteur in vitro sur les neurones traités par l'oxaliplatine au cours d’études de viabilité cellulaire ainsi qu’in vivo dans les modèles murins de neuropathies périphériques induites par l'oxaliplatine et le diabète. L'association de cette molécule avec l'oxaliplatine pourrait augmenter l'indice thérapeutique de cette chimiothérapie, en potentialisant ses effets antitumoraux tout en diminuant la neurotoxicité. L’ubiquité des propriétés neuroprotectrices de la benztropine a été démontrée sur des neuropathies périphériques résultants d’autres étiologies. Nous avons ici décrit deux molécules permettant de conserver l’efficacité antitumorale du traitement par oxaliplatine tout en limitant ses effets neurotoxiques. Nous avons décrit les mécanismes par lesquels ces molécules exercent leur neuroprotection. Les résultats prometteurs obtenus au cours de ces travaux permettent d’envisager l’utilisation en clinique de ces molécules afin de prévenir non seulement les neuropathies périphériques induites par l'oxaliplatine, mais aussi les neuropathies périphériques résultant d'autres étiologiesPlatinum-based chemotherapies have been shown to elicit their anti-tumoral effects by compromising DNA integrity. These impairments ultimately lead to a burst in oxidative stress which in turn promotes cell death processes. Oxaliplatin, a platinum-based antineoplastic drug is usually indicated in secondary metastatic colon cancers and colorectal cancers and mediates a rise in reactive oxygen species through the depletion of reduced glutathione in cancerous cells. This chemotherapy is indicated as a frontline and an adjuvant treatment and similarly to other platinum-based chemotherapies, it warrants for particular caution. Most patients receiving oxaliplatin develop peripheral neuropathies. This neurodegeneration is a limiting factor of this chemotherapy since it may require the lowering of dosage or even the interruption of the treatment if this side-effect is assessed as a grade 3 peripheral neuropathy. Neurological toxicities may manifest within hours of injection as an acute form or as a chronic form resulting from cumulated high-dosage injections. The acute form, characterized by transient paresthesia and myotonia, is reversible and usually resolves within days while the chronic form presents persistent paresthesia and thermoalgia resulting from distal axonal degradation and demyelination of large fibers. Inflammatory pathways have also been incriminated in the etiology of this neurodegeneration. Niclosamide, a teniacide known to downregulate Stat3, Wnt, Notch and Beta-catenin pathways was investigated in vitro and in vivo. Having previously demonstrated this compound’s anti-inflammatory properties in systemic sclerosis, we sought to investigate whether niclosamide could also prevent oxaliplatin’s neurotoxicity. Niclosamide demonstrated neuroprotection both in vitro on oxaliplatin-treated neurons and in vivo in models of oxaliplatin-induced peripheral neuropathies. Niclosamide is used in humans with limited side-effects. The association of this molecule with oxaliplatin could increase the therapeutic index of this chemotherapy. Benztropine is an inhibitor of muscarinic M1 and M3 receptors with known remyelinating potential in the central nervous system by promoting oligodendrocytes precursor cells differentiation and proliferation. The differential distribution between subtypes of receptors can allow the specific targeting of tumor cells, namely through the inhibition of autocrine acetylcholine signaling. This compound is well tolerated and does not elicit any immunological reaction upon its administration. These observations of potential for both, preventing neurotoxicity as well as increasing the efficacy profile of neurotoxic chemotherapies, prompted us to investigate this M1 and M3 receptors inhibitor. Benztropine demonstrated neuroprotection in vitro on oxaliplatin-treated neurons as demonstrated by viability assays studies as well as in vivo in models of oxaliplatin-induced as well as diabetic peripheral neuropathies. The association of this molecule with oxaliplatin could increase the therapeutic index of this chemotherapy, potentiate this chemotherapy’s antitumoral effects against certain cancers as well as decrease the occurrence of diabetic neuropathies, a prevalent complication of diabetes. We have herein described two molecules which allow oxaliplatin treatment to exert its cytotoxic effects without eliciting its neurotoxicity. Furthermore, we have described the mechanisms by which these molecules exert their neuroprotection. The neuroprotective abilities of one of these molecules have also been broadened by the study of other types of peripheral neuropathies, namely diabetic neuropathies. The promising results obtained over the course of these works allow for optimism in the prospect of finding therapies to counteract not only oxaliplatin-induced peripheral neuropathies but peripheral neuropathies resulting from other etiologies
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Azarm, Asieh. „Effect of oxaliplatin on HCT116 P53+/- colon cancer cells“. Thesis, Högskolan i Skövde, Institutionen för vård och natur, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-5451.
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Oxaliplatin as an effective chemotherapeutic agent in FOLFOX regimens is using to treat colorectal cancer. In this study we investigate cytotoxicity of Oxaliplatin as single chemotherapeutic agent toHCT116P53+/- to identify molecular mechanism of Oxaliplatin action in induction of apoptosis pathway. Oxaliplatin exposure to HCT116P53+/- colorectal cell lines with deficiency of mismatch repair characteristic resulted to decrease the number of viable cells through apoptosis. Effective Oxaliplatin concentrations (IC50) which inhibit 50% of cell viability were determined using XTT method. Standard curve and time-dependent assay performed to confirm IC50 concentration. Western blot analysis demonstrated relocalization of Bax to mitochondria and induction of intrinsic apoptosis pathway resulted Oxaliplatin exposure. Inactivation of Bax in HCT116P53+/- will result significant reduction in number of viable cells following treatment with Oxaliplatin
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Golf, Alexander. „Eine randomisierte Phase-II-Studie mit Capecitabin/Oxaliplatin versus Gemcitabin/Capecitabin versus Gemcitabin/Oxaliplatin bei Patienten mit lokal fortgeschrittenem inoperablem oder metastasiertem Pankreaskarzinom“. Diss., lmu, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-108951.
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Gong, Peng Chaney Stephen G. „Modeling conformational dynamics of cisplatin and oxaliplatin adducts with DNA“. Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,496.
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Thesis (M.S.)--University of North Carolina at Chapel Hill, 2006.Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Master of Science in the Department of Biomedical Engineering." Discipline: Biomedical Engineering; Department/School: Medicine.
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POZZI, ELEONORA. „OXALIPLATIN-INDUCED PERIPHERAL NEUROTOXICITY IN MOUSE MODELS: DIFFERENT TREATMENT SCHEDULES AND FOCUS ON OXIDATIVE STRESS“. Doctoral thesis, Università degli Studi di Milano-Bicocca, 2020. http://hdl.handle.net/10281/261949.
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La tossicità dei farmaci antitumorali rappresenta una delle principali limitazioni nella pratica clinica. Tra gli effetti collaterali dei farmaci chemioterapici, la neurotossicità periferica è uno dei più invalidanti per i pazienti malati di cancro.
Oxaliplatino (OHP), un composto ampiamente usato per il trattamento del carcinoma del colon-retto metastatico, è uno dei farmaci antineoplastici più neurotossici. I pazienti possono sviluppare due forme clinicamente distinte di neuropatia periferica: una forma acuta aggravata dal freddo ed una neuropatia sensoriale distale cronica. A causa della mancanza di efficaci terapie farmacologiche in grado di prevenire e/o alleviare i sintomi neuropatici, la riduzione o l'interruzione della dose di OHP è spesso necessaria. Nonostante approfondite ricerche, la patogenesi della neurotossicità periferica indotta da OHP (OIPN) è ancora in gran parte sconosciuta.
In letteratura sono descritti numerosi studi preclinici in vivo, diversi tra loro per la schedula di trattamento con OHP utilizzata, tuttavia la caratterizzazione della neurotossicità periferica è limitata. Infatti, per verificare l'insorgenza della OINP, oltre alla valutazione del dolore neuropatico, dovrebbero essere effettuate analisi neurofisiologiche ed istopatologiche.
La disfunzione mitocondriale è stata recentemente suggerita come possibile meccanismo coinvolto nell'insorgenza della neurotossicità periferica indotta dai farmaci chemioterapici.
Il primo obiettivo di questo lavoro è stato confrontare tre modelli murini di OIPN pubblicati con il modello murino di OIPN attualmente in uso nel nostro laboratorio, mediante una valutazione multimodale. Inoltre, dato il potenziale ruolo dello stress ossidativo nella patogenesi della neuropatia periferica, è stata analizzata la possibilità che il trattamento con OHP potesse indurre stress ossidativo e disfunzione mitocondriale.
I risultati di questo studio indicano che una singola dose di OHP 5 mg/kg somministrata per via endovenosa è in grado di riprodurre le caratteristiche cliniche della forma acuta della OIPN. D'altra parte, al fine di riprodurre le caratteristiche cliniche della OIPN cronica, è necessario un trattamento prolungato con OHP. Sono state osservate alterazioni delle ampiezze dei nervi caudali e digitali, allodinia meccanica ed una riduzione della densità delle fibre nervose intraepidermiche solo dopo 4 settimane di OHP 5 mg/kg somministrato per via endovenosa due volte a settimana, schedula attualmente utilizzata nel nostro laboratorio. Pertanto, il nostro modello di laboratorio OHP è quello che meglio mima le caratteristiche della OIPN.
Per quanto riguarda l'aspetto patogenetico, questo studio non ha ben chiarito il ruolo della disfunzione dei mitocondri e dello stress ossidativo nell'insorgenza della OIPN. I livelli di stress ossidativo, dosando i TBARS, non sono aumentati considerevolmente nei DRG e nei nervi caudali dopo il trattamento con OHP con qualsiasi schedula utilizzata, mentre i nervi sciatici hanno mostrato un aumento dei livelli di TBARS a 2 settimane dopo una dose cumulativa di 20 mg/kg (endovena) ed a 4 settimane dopo 30 mg/kg (intraperitoneale). Inoltre, un aumento significativo dei livelli del complesso I della catena respiratoria ed una riduzione della forma fosforilata di DRP1 sono stati rilevati nei DRG prelevati dagli animali trattati con la nostra schedula di trattamento per 4 e 2 settimane, rispettivamente.
In conclusione, un modello animale affidabile dovrebbe essere in grado di valutare la neurotossicità acuta e cronica al fine di studiare i meccanismi alla base della OIPN. Definire un metodo di valutazione standard sarebbe utile per ottenere risultati coerenti tra diversi gruppi di lavoro. Inoltre, la disfunzione mitocondriale e lo stress ossidativo possono essere implicati nell'insorgenza della OIPN, ma sono necessarie ulteriori indagini.The toxicity of anticancer drugs represents one of the major limitation in their clinical use. Among the side effects of chemotherapy, peripheral neurotoxicity is one of the most disabling for cancer patients. Oxaliplatin (OHP) is one of the most neurotoxic antineoplastic drug widely used for the treatment of metastatic colorectal cancer. Patients undergoing OHP-regimen experience two clinically distinct forms of peripheral neuropathy: an acute cold-enhanced form and a chronic distal sensory neuropathy. Due to the lack of effective pharmacological therapies in preventing and/or alleviating neuropathic symptoms, OHP dose reduction or interruption is often mandatory. Despite extensive investigation, the pathogenesis of OHP-induced peripheral neurotoxicity (OIPN) is still largely unknown. In literature several preclinical in vivo studies, different from each other in schedules of OHP treatment, are described but the characterization of peripheral neurotoxicity is limited. In fact, to verify the OINP onset, in addition to the evaluation of neuropathic pain, neurophysiological and histopathological analyses should be assessed. Mitochondrial dysfunction has recently been suggested as putative mechanisms possibly involved in the onset and development of chemotherapy-induced peripheral neurotoxicity. Mitochondrial dysfunction and associated oxidative stress may result in chronic neuronal energy impairment leading to neuropathic symptoms. The first aim of this study was to compare OIPN mouse models reported in three published studies with OIPN mouse model currently used in our laboratory, using a multimodal assessment. Moreover, given the potential role of oxidative stress in the pathogenesis of peripheral neuropathy, the possibility that OHP treatment could induce oxidative stress and eventually mitochondrial dysfunctions has also been analysed. Taken together, the results of this study indicate that a single dose of OHP 5 mg/kg administrated in tail vein is able to reproduce the clinical features of acute OIPN. On the other hand, to reproduce the clinical features of chronic OIPN, prolonged OHP treatment is required. In fact, alterations in caudal and digital nerves amplitudes and mechanical allodynia together with a reduction in intraepidermal nerve fiber density were observed only after 4 weeks of OHP 5 mg/kg administrated intravenously twice a week, the schedule currently used in our laboratory. Changes in DRG morphometry were instead more commonly observed also in the other OHP schedules reproduced in this study. As a whole, these results suggested that our laboratory OHP model is the one which better mimic the OIPN features. Regarding the pathogenic aspect, this study is far from clarifying the role of mitochondrial dysfunction and oxidative stress in the onset of OIPN, even if some results have been obtained. In general, oxidative stress levels measured with TBARS assay did not increase considerably in DRG and caudal nerves following OHP treatment with any schedule used, whereas sciatic nerves showed an increase in TBARS level at 2 weeks after a cumulative dose at 20 mg/kg (intravenous administration) and at 4 weeks after 30 mg/kg (intraperitoneal administration). Furthermore, a significant increase in protein expression levels of respiratory chain complex I in DRG collected from the animals treated for 4 weeks with our OHP schedule was detected. In the same samples, a decrease in phosphoryled form of DRP1 was observed closely approximating significance after 2 weeks of OHP treatment, indicating reduced mitochondrial fission process. In conclusion, a reliable animal model should be able to evaluate acute and chronic neurotoxicity in order to study the mechanism underlying OIPN. Setting a standard method of evaluation would be useful to obtain consistent results among different workgroups. Moreover, mitochondrial dysfunction and oxidative stress may be implicated in the onset of OIPN but further investigations are required.
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ALBERTI, PAOLA. „NERVE EXCITABILITY TESTING IN ANIMAL MODELS OF OXALIPLATIN INDUCED PERIPHERAL NEUROTOXICITY: ION CHANNEL DYSFUNCTION AS A POSSIBLE PATHOGENETIC MECHANISM“. Doctoral thesis, Università degli Studi di Milano-Bicocca, 2019. http://hdl.handle.net/10281/241091.
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Questo progetto riguarda la neurotossicità periferica conseguente alla somministrazione di Oxaliplatino (OINP). Si tratta di una entità clinicamente rilevante poiché OIPN è una delle tossicità dose limitanti per il trattamento del cancro del colon retto, una delle neoplasie più diffuse a livello globale. OIPN si manifesta nella forma di una sindrome acuta ed una cronica. La forma acuta consiste in uno stato transitorio di ipereccitabilità assonale (i pazienti riportano parestesie freddo-indotte, crampi, spasmo mandibolare nelle 24-72 ore dopo l’infusione del farmaco). Questa sindrome acuta è stata messa in relazione con una canalopatia funzionale ed una crescente letteratura suggerisce come la forma acuta sia un fattore predisponente quella cronica; un ruolo chiave è stato attribuito ai canali per il sodio voltaggio dipendenti. La forma cronica, invece, consiste in una neuropatia sensitiva persistente/di lunga durata: le principali caratteristiche cliniche sono perdita di sensibilità e dolore neuropatico alle estremità degli arti. Questa forma cronica impoverisce la qualità di vita dei pazienti che sopravvivono al cancro dato che non esiste attualmente una cura per tale condizione. L’obiettivo del progetto qui presentato è stato quello di tornare a livello preclinico per verificare la possibile relazione causale fra le due sindromi. Per caratterizzare in maniera efficace la forma acuta in un modello animale in vivo (ratto), è stata applicata una innovativa tecnica di neurofisiologia avanzata: i test di eccitabilità assonale (NET). NET permette di testare, in vivo, variazioni delle conduttanze ioniche. All’inizio del progetto il modello animale di OINP è stato raffinato affinché esprimesse l’intero spettro dei fenomeni di OIPN. Una volta verificato il profilo che la forma di OIPN acuta induce ai NET, topiramato è stato utilizzato come possibile farmaco neuroprotettore, contando sulla sua efficacia nel ridurre lo stato di ipereccitabilità assonale. Topiramato è stato, infatti, selezionato sulla base delle sue proprietà farmacodinamiche nei confronti proprio dei canali del sodio voltaggio dipendenti. In una prima fase si è dimostrato che topiramato è in grado di prevenire le modificazioni acute indotte da oxaliplatino a livello assonale. E’ stato quindi verificato se ridurre la forma di tossicità acuta potesse modificare la storia naturale di quella cronica: topiramato è stato in grado di prevenire completamente l’esordio di una neuropatia conclamata come dimostrato con gli studi di conduzione nervosa, i test comportamentali ed i riscontri neuropatologici. Pertanto, una possibile strategia per prevenire le forme acuta e cronica di OIPN potrebbe essere ora suggerita, modulando le conduttanze dei canali del sodio voltaggio dipendenti. Questi risultati hanno un profilo altamente traslazione poiché tutte le misure di outcome neurofisiologico sono direttamente mutuate dal contesto clinico ed i dati di questo progetto possono essere quindi prontamente riportati in un trial clinico; inoltre, topiramato è una molecola già impiegata per uso clinico (le sue indicazioni principali sono emicrania ed epilessia).This project is focused on Oxaliplatin (OHP) Induced Peripheral Neurotoxicity (OIPN). This is a relevant clinical entity since it is one of the main limiting toxicities of the corner stone drug to treat colorectal cancer (one of the commonest neoplasms). OIPN consists of an acute and chronic syndrome. Acute OIPN is a transient state of axonal hyperexcitability (transient cold-induced paresthesia, cramps and jaw-spasms, lasting 24-72 hours after OHP administration). Acute OIPN has been linked to a transient channelopathy and there is a growing Literature showing that acute OIPN might predispose to chronic one. A pivotal role for sodium voltage-operated channels has been advocated for acute OIPN. Chronic OIPN is, instead, a disabling long-lasting sensory neuropathy: neuropathic pain and sensory loss at limb extremities are the main features. Chronic OIPN is detrimental for cancer survivor’s quality of life and there is no treatment for it. The aim of the project was to go back to the bench side to find a possible answer to this unmet clinical need. At a preclinical level, the possible causative correlation between the 2 syndromes was investigated. To fully characterize acute OIPN, in an in vivo rat model, Nerve Excitability Testing (NET) was used; this is an advanced and relatively new technique that allows to test, in vivo, ion conductances. At first a refinement of the animal model was obtained. Once ascertained changes at NET due to acute OIPN, topiramate was used as a tentative drug to decrease the state of axonal hyperexcitability; Topiramate was selected given its known pharmacodynamic properties affecting sodium voltage-operated channels. Topiramate was able to contain alterations due to acute OIPN; it was then tested if topiramate had effects on chronic OIPN too, thanks to its ability to decrease acute one. Data were rather promising: topiramate was able to fully prevent chronic neuropathy onset as demonstrated through nerve conduction studies, behavioral tests and neuropathology. Thus, a possible strategy to prevent both acute and chronic OIPN might be suggested, modulating sodium voltage operated channels. These findings have a high translational potential since selected outcome measures (nerve conduction studies and NET) are performed with the same devices/techniques used in clinical practice and topiramate is yet approved for clinical use (its main indications are epilepsy and migraine treatment).
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Liu, Jing. „Pharmacokinetics and pharmacodynamics of oxaliplatin alone and in combination with paclitaxel /“. The Ohio State University, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486462067843341.
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Descoeur, Juliette. „Implication des canaux ioniques dans l'hypersensibilité au froid induite par l'oxaliplatine“. Thesis, Montpellier 1, 2010. http://www.theses.fr/2010MON13509.
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L'oxaliplatine, largement utilisé dans le traitement du cancer colorectal, se singularise par la survenue très précoce, dés le début du protocole de chimiothérapie de troubles douloureux associés à la perception du froid (hypersensibilité au froid). De nombreux traitements ont été testés pour ces symptômes sans grand succès, c'est pourquoi le développement de nouveaux analgésiques est nécessaire. Le but de ce travail est de développer un modèle souris reproduisant cette hypersensibilité au froid et d'en rechercher les mécanismes physiopathologiques. Comme chez les patients, l'administration aigüe d'oxaliplatine entraîne une amplification importante de la perception du froid chez la souris. Nous montrons que ces symptômes sont médiés par les nocicepteurs exprimant le thermorécepteur TRPM8. Sur le plan du mécanisme physiopathologique, l'oxaliplatine favorise l'excitabilité de ces nocicepteurs en diminuant de manière drastique l'expression des plusieurs canaux potassiques (TREK1 et TRAAK en particulier), et en augmentant l'expression de canaux proexcitateurs tels que les canaux cationiques activés par l'hyperpolarisation (HCN1 notamment). Ces constatations sont confortées au niveau comportemental par l'analyse de la lignée de souris double KO pour TREK1 et TRAAK, et par l'utilisation de l'Ivabradine, un inhibiteur pharmacologique spécifique des canaux HCNs. L'ivabradine, déjà utilisé en clinique pour le traitement de l'insuffisance cardiaque, entraîne une disparition de l'hypersensibilité au froid induite par l'oxaliplatine. Collectivement, ces résultats suggèrent que l'oxaliplatine exacerbe la perception du froid en remodelant le patron d'expression de plusieurs canaux ioniques qui coordonnent la réponse au froid. L'ivabradine peut ainsi représenter un traitement sur mesure pour les neuropathies induites par l'oxaliplatineThe hallmark of oxaliplatin-induced neuropathy is a hypersensibility to cold that develops in nearly all patients ultimately leading to cessation of this chemotherapy treatment. To date, classical pain management strategies have failed to alleviate these painful symptoms, and hence there is a need for developing new and efficient analgesics. Here we report that, as in patients, oxaliplatin mediates a clear development of exaggerated perception of cold temperatures in mice. These symptoms are mediated by nociceptors expressing the thermoreceptor TRPM8. Mechanistically, we find that oxaliplatin promotes excitability in nociceptors drastically lowering the expression of distinct potassium channels (TREK1, TRAAK) that act as excitability brakes for cold perception, and by increasing the expression of pro-excitatory channels such as the hyperpolarisation-activated channels (HCNs). These findings are corroborated by the analysis of the TREK1-TRAAK null mice, and by the use a specific HCN channel inhibitor abolishing the oxaliplatin-induced cold hypersensibility. Collectively, these results suggest that oxaliplatin exacerbates cold perception in cold sensing neurons by transcriptionally remodeling a combination of ionic conductances that together shape the final response to cold. A direct promising clinical consequence of these findings for patients would be that the HCN inhibitor ivabradine could represent a tailored treatment for oxaliplatin-induced neuropathy
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Azevedo, Maria Isabel Carneiro de. „Effect of flavonoids rutin and quercetin in peripheral neuropathy induced sensitive oxaliplatin“. Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=10494.
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Oxaliplatin is a third-generation platinum compound and the first-line treatment for colorectal cancer. The main limiting factor in oxaliplatin treatment is painful neuropathy that is difficult to treat. This side effect has been studied for several years, but its full mechanism is still inconclusive, and effective treatment does not exist. Data suggest that oxaliplatinâs initial neurotoxic effect is peripheral and oxidative stress-dependent. A spinal target is also suggested in its mechanism of action. The flavonoids rutin and quercetin have been described as cell-protecting agents because of their antioxidant, antinociceptive, and anti-inflammatory actions. We proposed a preventive effect of these agents on oxaliplatin-induced painful peripheral neuropathy based on their antioxidant properties. Methods: Oxaliplatin (1 mg/kg, i.v.) was injected in male Swiss mice, twice per week for 4 weeks. The development of sensory alterations, such as thermal allodynia and mechanical hypernociception, was evaluated using the tail immersion test in cold water (10ÂC) and the von Frey test. Rutin and quercetin (25-100 mg/kg, i.p.) were injected 30 min before each oxaliplatin injection. The animalsâ spinal cords were removed for histopathological and immunohistochemical evaluation and malondialdehyde and non-protein sulfhydryl group assays. Results: Oxaliplatin significantly reduced thermal and mechanical nociceptive thresholds, effects prevented by quercetin and rutin at all doses. Fos immunostaining in the dorsal horn of the spinal cord confirmed these results. The oxidative stress assays mainly showed that oxaliplatin induced peroxidation in the spinal cord and that rutin and quercetin decreased this effect. The flavonoids also decreased inducible nitric oxide synthase and nitrotyrosine immunostaining in the dorsal horn of the spinal cord. These results suggest that nitric oxide and peroxynitrite are also involved in the neurotoxic effect of oxaliplatin and that rutin and quercetin can inhibit their effect in the spinal cord. We also observed the preservation of dorsal horn structure using histopathological analyses. Conclusions: Oxaliplatin induced painful peripheral neuropathy in mice, an effect that was prevented by rutin and quercetin. The mechanism of action of oxaliplatin appears to be at least partially oxidative stress-induced damage in dorsal horn neurons, with the involvement of lipid peroxidation and protein nitrosylation.Oxaliplatina (OXL) à um agente antineoplÃsico de terceira geraÃÃo, com potente atividade citotÃxica em vÃrios tipos de cÃncer, mas apresenta um efeito neurotÃxico importante que causa uma severa e dolorosa neuropatia perifÃrica. Dados da literatura tambÃm sugerem que o efeito neurotÃxico inicial da OXL seria dependente do estresse oxidativo, nos tecidos perifÃricos. Os flavonÃides Rutina (RT) e Quercetina (QC) foram descritos como agentes protetores celulares por sua aÃÃo antioxidante, assim como por seus efeitos antiinflamatÃrios e antinociceptivos. O objetivo deste estudo à investigar o efeito do tratamento com RT e QC na neuropatia sensitiva perifÃrica (NSP) induzida pela OXL em camundongos. O estudo foi aprovado pelo Comità de Ãtica em Pesquisa Animal da Universidade Federal do Cearà (n 36/2011). A neuropatia sensitiva foi induzida em camundongos Swiss machos (25-30 g), atravÃs de duas injeÃÃes por semana de OXL (1 mg/kg, e.v.) durante 4,5 semanas, no total de nove injeÃÃes, juntamente com a avaliaÃÃo de testes nociceptivos semanais. AlodÃnia tÃrmica foi avaliada pelo teste de imersÃo da cauda em Ãgua fria (10 ÂC), e hipernocicepÃÃo mecÃnica plantar pelo teste eletrÃnico de Von Frey. Os animais tratados com OXL foram divididos nos grupos: grupo controle (prÃ-tratado com salina), e trÃs grupos prÃ-tratados com RT ou QC (25, 50 e 100 mg/kg, i.p), 30 min antes de cada injeÃÃo de OXL. No final dos experimentos, as medulas espinhais foram removidas e processadas para avaliaÃÃo histopatolÃgica e imunohistoquÃmica. Em outros experimentos a medula espinha tambÃm foi retirada para testes bioquÃmicos (MDA e NP-SH). Nossos resultados mostraram que a OXL reduziu significativamente (p < 0,05) tanto o limiar nociceptivo tÃrmico como mecÃnico. O tratamento com QC, preveniu esses efeitos (p< 0,05) em todas as doses (efeito mÃximo na dose de 50 mg/kg), aumentando o limiar em 68,6 % para alodÃnia tÃrmica e em 47,6 % para hipernocicepÃÃo mecÃnica. O tratamento com RT tambÃm preveniu esses efeitos (p < 0,05) em todas as doses (efeito mÃximo na dose de 50 mg/kg) aumentando o limiar em 448 % para alodÃnia tÃrmica e em 25,5 % para hipernocicepÃÃo mecÃnica. A imunohistoquÃmica mostrou que a RT e QC diminuÃram a imunoexpressÃo para c-fos, NOSi (oxido nÃtrico sintase induzida) e nitrotirosina, no corno posterior da medula espinhal, quando comparada ao grupo controle. OXL aumentou significativamente os nÃveis de MDA, mas nÃo de NP-SH com inibiÃÃo pelo tratamento com RT e QC. Nossos resultados mostraram que RT e QC tem efeito antinociceptivo em ambos os testes, tÃrmico e mecÃnico, juntamente com a inibiÃÃo da imunoexpressÃo para c-fos pela QC na neuropatia sensitiva perifÃrica da OXL. AlÃm disso, a QC foi capaz de inibir a imunoexpressÃo para nitrotirosina e para NOSi no corno posterior da medula espinhal, indicando um possÃvel mecanismo envolvendo NO e estresse oxidativo. Os dados sugerem que RT e QC podem ter um efeito neuroprotetor, vindo a ser uma alternativa promissora na prevenÃÃo a neuropatia sensitiva perifÃrica causada pela OXL na quimioterapia do CÃncer.
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趙, 萌. „オキサリプラチンによる急性末梢神経障害におけるTRPA1チャネルの関与“. 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188729.
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Schlemmer, Frédéric. „Mécanismes de la chimiothérapie immunogène“. Thesis, Paris 11, 2013. http://www.theses.fr/2013PA11T075.
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L’amélioration constante du pronostic des pathologies cancéreuses est le fruit des progrès réalisés dans leur prévention, leur dépistage, leur diagnostic et leur traitement. Malgré l’avènement récent des thérapies ciblées, la chimiothérapie conventionnelle reste souvent le seul recours pour des patients atteints de cancer non opérable ou non éligibles pour ces thérapeutiques novatrices. Certaines chimiothérapies conventionnelles (anthracyclines et oxaliplatine notamment) ont la capacité d’entrainer une mort des cellules tumorales dont les caractéristiques permettent d’induire une réponse immunitaire antitumorale efficace. Cette réponse immunitaire antitumorale spécifique agirait en synergie avec l’effet cytotoxique direct de ces drogues, participant ainsi à leur efficacité. La réponse immunitaire antitumorale induite par la chimiothérapie dépend de plusieurs mécanismes moléculaires et cellulaires clefs identifiés récemment. L’induction d’un stress du réticulum endoplasmique (RE) est à l’origine de l’exposition d’une protéine chaperonne résidente du RE, la calréticuline (CRT), à la surface des cellules mourantes, servant alors de signal de phagocytose pour les cellules dendritiques. La libération dans le milieu extracellulaire de signaux de danger est également essentielle : la protéine nucléaire High Mobility Group Box 1 (HMGB1) sert ainsi de ligand pour le Toll-like récepteur 4 (TLR4), présent à la surface des cellules dendritiques et son activation favorise l’apprêtement et la présentation des antigènes tumoraux aux lymphocytes T cytotoxiques. L’adénosine-5'-triphosphate (ATP) est également libéré par les cellules tumorales, entrainant l’activation des récepteurs purinergiques P2RX7 présents à la surface des cellules dendritiques, activant l’inflammasome NLRP3 et entrainant la libération d’IL-1 par les cellules dendritiques, favorisant alors l’orientation de la réponse immunitaire vers une réponse de type TH1 et la production d’interféron par les lymphocytes T cytotoxiques. Dans ce travail, nous avons cherché à comparer la capacité de deux drogues issues d’une même classe de chimiothérapie, les sels de platine, à induire une mort cellulaire immunogène des cellules tumorales. Grace à des expériences in vitro et in vivo (modèles murins de vaccination antitumorale et de chimiothérapie sur tumeurs établies), nous avons pu montrer que l’oxaliplatine (OXP), contrairement au cisplatine (CDDP), avait la capacité d’induire une mort immunogène des cellules de cancer colique et que cette différence intra-classe dépendait de la capacité respective de ces deux drogues à entrainer un des phénomènes clés de l’induction d’une mort cellulaire immunogène, l’exposition de la CRT à la surface des cellules tumorales mourantes. Nous avons également pu montrer que l’induction d’une mort cellulaire immunogène des cellules de cancer colique par l’oxaliplatine avait une relevance clinique chez l’homme, l’existence d’un polymorphisme perte-de-fonction du gène tlr4 affectant le pronostic (survie sans progression) de patients traités par chimiothérapie pour un cancer colique métastatique. Par la suite, nous avons mis au point des biosondes permettant d’étudier à grande échelle, à l’aide d’une plateforme de vidéo-microscopie automatisée, la capacité de différentes drogues à induire les différents phénomènes clefs de la mort cellulaire immunogène des cellules tumorales (exposition de la CRT, libération d’HMGB1 et d’ATP). Nous avons ainsi pu montrer que la correction pharmaceutique du défaut d’activation d’un stress du réticulum endoplasmique par le cisplatine permettait de restaurer l’immunogénicité de la mort cellulaire induite par cette chimiothérapie. Ces résultats ouvrent la voie à la découverte de nouvelles molécules susceptibles, à elles seules ou en association à d’autres thérapies connues, d’améliorer le pronostic des néoplasiesThe steady improvement of cancer prognosis is the result of progress in cancer prevention, screening, diagnosis and treatment. Despite the recent advent of targeted therapies, conventional chemotherapy often remains the only solution for patients with non-operable cancer or not eligible for these novel therapies.Some conventional chemotherapy (including anthracyclines and oxaliplatin) has the ability to cause tumor cells death with characteristics able to induce an effective antitumor immune response. This specific antitumor immune response would be synergistic with the direct cytotoxic effect of these drugs and contribute to their efficacy. The antitumor immune response induced by chemotherapy depends on several key cellular and molecular mechanisms recently identified. The induction of an endoplasmic reticulum (ER) stress is necessary for the exposure of calreticulin (CRT), an ER-resident chaperone protein, on the surface of dying cells, then acting as a phagocytosis signal for dendritic cells. Release of danger signals into the extracellular medium is also essential. The nuclear protein High Mobility Group Box 1 (HMGB1) is a ligand of the Toll-like receptor 4 (TLR4) on the surface of dendritic cells. TLR4 activation promotes the processing of tumor antigens and their presentation to cytotoxic T lymphocytes. Adenosine-5'-triphosphate (ATP) is also released by tumor cells, leading to the activation of the purinergic receptors P2RX7 expressed on the surface of dendritic cells, activating the NLRP3 inflammasome and causing the release of IL-1β by dendritic cells, while promoting the orientation of the immune response towards a TH1 response and the production of γ-interferon by cytotoxic T lymphocytes.In this work, we aimed to compare the ability of two drugs of a same class of chemotherapy, the platinum derivates oxaliplatin (OXP) and cisplatin (CDDP), to induce immunogenic death of tumor cells. Thanks to in vitro and in vivo experiments (models of tumor vaccination and chemotherapy on established tumors in mice), we showed that OXP, in contrast to CDDP, has the ability to induce immunogenic death of colon cancer cells. This intra-class difference depends on the ability of each drug to cause one of the key phenomena of immunogenic cell death: the induction of the exposure of the CRT to the surface of dying tumor cells. We could also show that the induction of immunogenic death of colon cancer cells by OXP had clinical relevance in humans. Indeed, the existence of a loss-of-function polymorphism of tlr4 affects the prognosis (PFS) of patients treated with OXP-based chemotherapy regimen for a metastatic colorectal cancer. Subsequently, we developed biosensors to study the ability of different drugs to induce key phenomena of cell death immunogen tumor cells (CRT exposure, HMGB1 and ATP release) using high-content screening by an automated video-microscopy platform. We showed that a pharmaceutical correction of the inability of cisplatin to induce an endoplasmic reticulum stress could restore the immunogenicity of cisplatin-induced tumor cell death. These results open the way to the discovery of new molecules that, alone or in combination with other known therapies, could improve the prognosis of cancer
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Demontoux, Lucie. „Rôle de l’hypotonie dans la réponse à la chimiothérapie intra-péritonéale : étude des effets sur les cellules cancéreuses et la mort immunogène induite“. Thesis, Bourgogne Franche-Comté, 2018. http://www.theses.fr/2018UBFCI012/document.
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La Chimiothérapie IntraPéritonnéale (CIP) est utilisée couramment pour traiter le cancer colorectal métastatique. Cependant il n'existe pas de protocole standardisé.Le but de ce projet a été de modéliser cette chimiothérapie in vitro et de comprendre le rôle de l'hypotonie dans ce modèle et son impact sur la mort des cellules cancéreuses.Nous avons déterminé les conditions optimales de traitement sur les cellules cancéreuses coliques humaines HCT116 à savoir une exposition des cellules pendant 30 minutes à 400µM d'oxaliplatine en conditions hypotoniques (G2.5%) à 37°C. Ces résultats ont été validés sur différentes lignées cancéreuses coliques humaines et murine. Nous avons également montré que ces conditions de traitements étaient également capables d’augmenter la cytotoxixité d’autres dérivés du platine comme le cisplatine et le carboplatine.La mort cellulaire induite par ce traitement en hypotonie est de type apoptotique, Et peut s’expliquer par une augmentation de l’incorporation intracellulaire d'oxaliplatine, en partie due à l'activation et à la trimérisation du transporteur du cuivre CTR1.Le traitement par l'oxaliplatine et le cisplatine (mais pas par le carboplatine) en hypotonie entraine également les stigmates de la mort immunogène, à savoir l'exposition de la calréticuline à la membrane, la libération d'ATP et le relargage d'HMGB1, suggérant que l'hypotonie permettrait d'entrainer la mort immunogène et une réponse du système immunitaire lors de cette modélisation de CIP.Enfin, in vivo nous avons pu mettre en évidence que le traitement de métastases intrapéritonéales de souris Balb/c par une injection intrapéritonéale d'oxaliplatine en hypotonie permettait un ralentissement de l’apparition de nodules tumoraux et une augmentation de la survie des souris.Ainsi, nous avons pu mettre en évidence dans ce travail que l'hypotonie est un des paramètres fondamentaux de la CIP et suggère que son utilisation pourrait permettre d'augmenter l’efficacité de la CIP et de prolonger la survie des patientsIntraPeritoneal Chemotherapy (IPEC) is commonly used to treat colorectal cancer metastases. However there is no standardized protocol.The aim of this work was to model this chemotherapy in vitro and to understand the role of hypotonic conditions in this model and its impact on cell death.We determined that the optimal treatment parameters on HCT116 human colon cancer cells, were an exposure of the cells for 30 minutes to 400μM of oxaliplatin under hypotonic conditions (G2.5%) at 37 °C. These results have been validated on various human and murine colic cancer cell lines. We have also shown that these treatment conditions are also able to increase the cytotoxicity of other platinum derivatives such as cisplatin and carboplatin.The cell death induced by this treatment in hypotonia is apoptosis, and can be explained by an increase in the intracellular incorporation of oxaliplatin, partly due to the activation and trimerization of the CTR1 copper transporter.Treatment with oxaliplatin and cisplatin (but not carboplatin) in hypotonia also leads to the stigmata of immunogenic death, e.i. exposure of calreticulin at the membrane, release of ATP and HMGB1 in the supernatant, suggesting that hypotonia would entail immunogenic death and an immune system response during this IPEC modeling.Finally, we have been able to demonstrate in vivo that the treatment of intraperitoneal metastases of Balb/c mice by an intraperitoneal injection of oxaliplatin in hypotonia slowed down tumor nodules appearance and increased survival of the mice.Thus, in this work we highlighted that hypotonia is one of the fundamental parameters of IPEC which suggests that its use could make it possible to increase the efficacy of IPEC and maybe to prolong the survival of patients
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Novotna, Jaroslava. „Exposition von OP-Personal gegenüber Cis/Oxaliplatin bei Operationen nach dem HIPEC-Verfahren“. Diss., lmu, 2012. http://nbn-resolving.de/urn:nbn:de:bvb:19-151475.
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Cushing, Merta, und Thao Truong. „Efficacy and toxicity of capecitabine/oxaliplatin (XELOX) versus 5-fluorouracil/leucovorin/oxaliplatin (FOLFOX) in adjuvant and metastatic treatment of colorectal cancer in patients at the Southern Arizona Veteran Affairs Health Care System“. The University of Arizona, 2017. http://hdl.handle.net/10150/624166.
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Class of 2017 AbstractObjectives: To determine the efficacy and toxicity of fluorouracil/leucovorin/oxaliplatin (FOLFOX) versus capecitabine/oxaliplatin (XELOX) in the treatment of colorectal cancer (CRC) in the adjuvant (aCRC) and metastatic (mCRC) setting in Veterans at the Southern Arizona Veteran Affairs Health Care System (SAVAHCS). Methods: A retrospective chart review was conducted to collect efficacy and toxicity data. Subjects were included based on age, treatment setting and regimen in the preset 5-year period, and appropriate diagnosis via International Classification of Diseases-Revision 9 (ICD-9) codes. Efficacy was measured via 1-year disease-free survival (DFS) for aCRC, progression-free survival (PFS) for mCRC, and overall survival (OS) for both settings. Results: A total of 79 subjects were initially enrolled with 51 and 54 all-male subjects included in the efficacy and toxicity analysis, respectively. Mean range of age was 63-72 years old. Subjects were divided into four groups: FOLFOX aCRC (17) and mCRC (19), XELOX aCRC (10) and mCRC (8). No difference was found in 1-year DFS and OS between aCRC groups, and PFS between mCRC groups; a higher incidence of 1-year OS with FOLFOX in the mCRC setting was noted (p = 0.03). No difference was found in toxicity between FOLFOX and XELOX, except a higher incidence of hand-foot syndrome in XELOX (p = 0.0007). Conclusions: Efficacy between FOLFOX and XELOX in aCRC and mCRC is similar, while toxicity is slightly more prevalent in XELOX due to increased hand-foot syndrome incidence. These findings agreed with the results reported by prospective clinical trials.
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Ruiz, de Porras Fondevila Vicente. „Estudi de l'efecte de la curcumina en la reversió de la resistència adquirida a oxaliplatí mitjançant la inhibició de la via de senyalització de NF-kB en models cel·lulars de càncer colorectal“. Doctoral thesis, Universitat Autònoma de Barcelona, 2016. http://hdl.handle.net/10803/399823.
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La resistència a oxaliplatí és un procés multifactorial i complex que afecta al desenllaç clínic dels pacients amb càncer colorectal (CRC) metastàtic tractats amb aquest fàrmac. La desregulació de la via de senyalització de NF-κB ha estat proposada com un important mecanisme implicat en aquest fenòmen. En aquest treball, hem observat que NF-κB es troba hiperactivat en models in vitro de resistència adquirida a oxaliplatí però la seva activació és atenuada mijançant l’addició de curcumina, un inhibidor no tòxic de NF-κB. El tractament concomitant d’oxaliplatí + curcumina va resultar ser més efectiu i sinèrgic en les línies cel·lulars amb resistència adquirida a oxalipatí promovent la reversió del seu fenotip resistent mitjançant la inhibició de la cascada de senyalització de NF-κB. L’anàlisi transcriptòmic va revelar la sobreexpressió de tres quimiocines regulades per NF-κB a nivell transcripcional , CXCL8, CXCL1 i CXCL2, en la línia resistent a oxaliplatí. Alhora, l’expressió d’aquestes quimiocines disminuia de manera més eficient en la línia resistent després del tractament combinat d’oxaliplatí + curcumina en comparació amb les cèl·lules sensibles a oxaliplatí. A més a més, el silenciament gènic de CXCL8 i CXCL1 es va traduir en un augment de la sensibilitat a oxaliplatí en les cèl·lules resistents mitjançant la inhibició de la via de senyalització Akt/NF-κB. Una alta expressió de CXCL1 en mostres fixades amb formol i incloses en parafina d’explants de metàstasis hepàtiques derivades de pacients amb CCR avançat es va associar amb la resposta al tractament combinat d’oxaliplatí + curcumina. En conclusió, els nostres resultats suggereixen que la combinació d’oxaliplatí + curcumina pot ser un tractament efectiu en pacients amb CCR i que l’expressió de CXCL1 podria utilitzar-se com a marcador predictiu de bona resposta a aquest tractament.Resistance to oxaliplatin is a complex process affecting the outcome of metastatic colorectal cancer (CRC) patients treated with this drug. De-regulation of the NF-κB signalling pathway has been proposed as an important mechanism involved in this phenomenon. In this work, we show that NF-κB was hyperactivated in in vitro models of oxaliplatin-acquired resistance but was attenuated by the addition of curcumin, a non-toxic NF-κB inhibitor. The concomitant combination of curcumin + oxaliplatin was more effective and synergistic in cell lines with acquired resistance to oxaliplatin, leading to the reversion of their resistant phenotype, through the inhibition of the NF-κB signalling cascade. Transcriptomic profiling revealed the up-regulation of three NF-κB-regulated CXC-chemokines, CXCL8, CXCL1 and CXCL2, in the resistant cells that were more efficiently down-regulated after oxaliplatin + curcumin treatment as compared to the sensitive cells. Moreover, CXCL8 and CXCL1 gene silencing made resistant cells more sensitive to oxaliplatin through the inhibition of the Akt/NF-κB pathway. High expression of CXCL1 in FFPE samples from explant cultures of CRC patients-derived liver metastases was associated with response to oxaliplatin + curcumin. In conclusion, we suggest that combination of oxaliplatin + curcumin could be an effective treatment, for which CXCL1 could be used as a predictive marker, in CRC patients.
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Puyo, Stéphane. „Recherche d’alternatives thérapeutiques aux taxanes dans les cancers de la prostate de hauts grades : identification d’une signature prédictive de la réponse à l’oxaliplatine“. Thesis, Bordeaux 2, 2011. http://www.theses.fr/2011BOR21842/document.
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Les cancers de la prostate sont classés en deux catégories. Les cancers de haut grade se distinguent des cancers de bas grade par une plus forte agressivité et un pronostic plus mauvais. Lorsqu’ils deviennent résistants à l’hormonothérapie, les cancers de haut grade sont traités par une chimiothérapie basée sur les taxanes. Néanmoins, les taux de réponse restent faibles. Il existe donc un réel besoin quant à l'identification d'alternatives thérapeutiques qui soient spécifiques de ce type de tumeur. Dans cette optique, notre travail a été de proposer une telle alternative par une approche qui prenne en compte la génétique spécifique des cancers de haut grade. Nous avons exploité une signature de 86 gènes dont le niveau d’expression permet de discriminer entre les tumeurs de haut et de bas grade. Par une approche in silico originale utilisant la banque de données du NCI, nous avons identifié 382 corrélations entre le niveau d’expression de 50 gènes et la sensibilité à 139 agents antiprolifératifs. Parmi ces corrélations, nous avons identifié une signature de 9 gènes qui est spécifique de la réponse à l’oxaliplatine. Cette signature a été confirmée sur le plan fonctionnel dans les lignées cancéreuses prostatiques DU145 et LNCaP. Nous avons donc fourni la preuve de concept que notre approche permet d’identifier de nouvelles molécules pouvant être utilisées en alternative aux taxanes pour traiter spécifiquement les cancers de haut grade. Cette stratégie permet aussi d’identifier de nouveaux marqueurs (gènes) régulant la sensibilité à certains médicaments. Nos résultats démontrent par exemple le rôle des gènes SHMT, impliqués dans la régulation du métabolisme monocarboné, dans la sensibilité spécifique à l’oxaliplatine par un mécanisme qui fait intervenir, du moins en partie, une dérégulation du niveau de méthylation global de l’ADNProstate cancers are classified in two categories. High grade cancers are distinguished from low grade cancers by their higher agressivity and worse prognostic. When they become refractory to hormone therapy, high grade cancers are treated with a taxane-based chemotherapy. However, response rates remain low. Therefore, there is a real need for the discovery of new therapeutic alternatives which are specific for this type of tumors. For that purpose, our work aimed at proposing such an alternative with a strategy that took into account the high grade genetic background. We exploited a signature of 86 genes for which expression level could distinguish between low grade and high grade tumours. With an original in silico approach, we searched the NCI databases and identified 382 correlations between 50 genes and the sensitivity to 139 antiproliferative agents. Among these, a signature of 9 genes was able to specifically predict cell response to oxaliplatin. This signature was validated at the functional level in two prostate cancer cell lines, DU145 and LNCaP. We have thus provided the proof-of-concept that our approach allows the identification of new drugs that can be used alternatively to taxanes in order to specifically treat high grade prostate cancers. This strategy also allows the identification of new markers (genes) regulating the sensitivity to various drugs. Our results demonstrate for example the implication of SHMT genes, which are involved in the regulation of the one-carbon metabolism, in the specific sensitivity to oxaliplatin, by a mechanism which involves, at least in part, the deregulation of the global level of DNA methylation
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Bouslimani, Amina. „Etude de la pénétration et du métabolisme intra-tumoral de l'oxaliplatine : proposition d'un nouveau mécanisme d'action“. Thesis, Montpellier 1, 2012. http://www.theses.fr/2012MON13506.
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L'oxaliplatine est un médicament anticancéreux utilisé dans la chimiohyperthermie intrapéritonéale (CHIP), pour le traitement des carcinoses péritonéales (CP). En dépit de l'efficacité de la CHIP, l'infiltration de l'oxaliplatine dans les tumeurs traitées est très peu connue. L'étude de la pénétration du médicament dans des tumeurs prélevées à partir de patients atteints de CP et traités CHIP, a fait l'objet de la première partie du projet de recherche. Par ailleurs, les mécanismes de transport du médicament jusqu'à l'ADN cellulaire n'ont pas été bien déterminés. Néanmoins, des hypothèses suggèrent que certains métabolites soufrés de l'oxaliplatine pourraient constituer des "formes réservoirs", capables de transporter le médicament jusqu'à l'ADN. La deuxième partie du projet a consisté à étudier de manière plus approfondie la réactivité d'un des métabolites soufrés de l'oxaliplatine. Nous avons développé une méthode d'imagerie par spectrométrie de masse MALDI/TOF, qui permet de déterminer la distribution de l'oxaliplatine et ses métabolites, dans les tumeurs humaines traitées CHIP. Nos résultats révèlent une pénétration du médicament limitée à quelques millimètres et une détection exclusive du métabolite oxaliplatine-méthionine (Ox-M) : un métabolite considéré « inactif », puisqu'il serait stable et incapable d'interagir avec l'ADN. Afin de démontrer la réactivité de ce métabolite, nous avons tout d'abord étudié son interaction avec les cibles de l'oxaliplatine, à savoir la guanine et l'ADN. Nos résultats démontrent la capacité de Ox-M à libérer la partie réactive de la molécule pour interagir avec la guanine, et former des adduits sur des duplexes d'oligonucléotides qui miment la structure de l'ADN. De plus, les adduits formés par Ox-M induisent un arrêt de l'élongation de l'ADN. Ces résultats démontrent la réactivité du métabolite Ox-M de l'oxaliplatine, et suggèrent son implication dans une nouvelle voie active du médicamentOxaliplatin is an anticancer drug used in Heated Intraoperative Chemotherapy (HIPEC) to treat peritoneal carcinomatosis. In spite of HIPEC efficiency, oxaliplatin penetration in treated tumors is not very well known. Study of oxaliplatin penetration in tumors of patients suffering from CP and treated with HIPEC, was the first part of the research project. Furthermore, transport mechanisms of the drug to cell DNA are not well established. Nevertheless, hypotheses suggest that some sulfur metabolites of oxaliplatin, could constitute "tanks" which are able to transport drug until DNA. The second part of this project aimed to study more deeply the reactivity of oxaliplatin sulfur metabolites. We have developed a MALDI imaging mass spectrometry method, which allows studying the distribution of oxaliplatin and its metabolites in human tumors. Our results reveal a drug penetration limited to few millimeters and an exclusive detection of the oxaliplatin- methionine metabolite (Ox-M): a supposed "Inactive" metabolite, because of its stability that prevents its interaction with DNA. To provide evidence of Ox-M reactivity, we studied its interaction with oxaliplatin targets: guanine and DNA. Our results showed that Ox-M is able to release the active part of the molecule to interact with guanine, and to form adducts on oligonucleotides duplexes that mimic DNA structure. Moreover, Ox-M adducts induce an arrest of DNA elongation. These results suggest the implication of Ox-M in a new active pathway of oxaliplatin cytotoxicity
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Delmotte, Jean-Baptiste. „Etude des marqueurs de la neuropathie à l’oxaliplatine“. Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS600/document.
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L’oxaliplatine (OXA) est un anticancéreux couramment employé en oncologie, son efficacité étant reconnue en première ligne dans le traitement de nombreux cancers. Cependant, son utilisation est limitée par l’apparition de neuropathies impactant la qualité de vie du patient. Pour identifier et étudier des marqueurs cliniques, plasmatiques et électrochimiques de neuropathie chronique induite par l’oxaliplatine (NPIO), deux études pilotes (LIPIDOXA et CANALOXA) ont été réalisées. Les patients de l’étude LIPIDOXA ont été inclus avant traitement par OXA et ont été évalués avant traitement, tout au long du traitement et six mois après l’arrêt. Entre mai 2014 et juin 2016, 35 patients ont été inclus. L’apparition d’une hypoesthésie thermique a été mise en évidence six mois après arrêt de l’OXA, révélateur d’un processus neurotoxique qui se poursuit même après l’arrêt du traitement. L’étude des marqueurs plasmatiques a révélé, en fin de traitement, une augmentation de la production de prostaglandines E2, un niveau moins élevé de stress oxydant chez les patients souffrant d’une neuropathie de grade 2 ainsi qu’une diminution de la concentration des triglycérides polyinsaturés associée à une tendance à l’augmentation des acides gras libres polyinsaturés. Les patients de l’étude CANALOXA, tous neuropathiques, ont été inclus en cours de traitement par OXA et évalués une seule fois. Entre avril 2016 et mars 2017, 36 patients ont été inclus. Les valeurs des conductances électrochimiques de la peau (ESC) étaient pathologiques pour un tiers des patients. Les valeurs d’ESC étaient bien corrélées avec le score de douleur neuropathique.Ces marqueurs sont cependant peu spécifiques et semblent d’apparition tardive. Aussi, ils sont difficilement utilisables en pratique clinique pour un éventuel suivi de la tolérance neurologique au traitement. Au-delà de l’apport clinique et thérapeutique modéré, ce travail renforce la compréhension de la physiopathologie de la NPIO dans le domaine de la neuropathie à petites fibres, les processus inflammatoires associés et la perturbation du métabolisme lipidique chez le patient traité par oxaliplatine.La complémentarité et les similarités de ces travaux rappellent que la prise en charge du patient doit être globale et conjuguer des éléments variés au sein desquels le patient doit rester au cœur de la gestion de la NPIO. Ce projet de recherche s’inscrit dans une dynamique d’amélioration continue et les résultats des études pilotes constituent une base pour approfondir les travauxOxaliplatin (OXA) is an anti-cancer drug widely used in oncology, its effectiveness is recognized in first-line chemotherapy regimen in many cancers. However, its use is limited by an onset of a disabling peripheral neuropathy with a negative association with quality of life. To identify and study clinical, plasma and electrochemical markers of oxaliplatin-induced chronic neuropathy (OIPN), two pilot studies (LIPIDOXA and CANALOXA) were conducted.Patients in the LIPIDOXA study were included prior to OXA treatment and were evaluated before treatment, during treatment, and six months after discontinuation. Between May 2014 and June 2016, 35 patients were included. The onset of thermal hypoaesthesia was highlighted six months after OXA completion, revealing a neurotoxic process that extends beyond treatment. The study of plasma markers revealed, at the end of treatment, an increase of prostaglandins E2 release, a lower level of oxidative stress in patients suffering from grade-2 neuropathy as well as a decrease in the concentration of polyunsaturated triglycerides associated with a tendency in polyunsaturated free fatty acids increase. The patients in the CANALOXA study, all neuropathic, were included during treatment with OXA and evaluated once. Between April 2016 and March 2017, 36 patients were included. The values of the electrochemical conductances of the skin (ESC) were pathological for one third of patients. ESC values were well correlated with the neuropathic pain score.However, these markers are sparsely specific and seem to be of late onset. Thus, they are are not suitable for a possible monitoring of the neurological tolerance of the treatment in the current care practice. Beyond the moderate clinical and therapeutic contribution, this work strengthens the understanding of the pathophysiology of OIPN in the field of small-fiber neuropathy, the associated inflammatory processes and the disruption of lipid metabolism in the patient treated with oxaliplatin.The complementarity and similarity of this work remind us that the patient care must be global and combine various elements in which the patient must remain at the heart of the management of the OIPN. This project takes part in a dynamic of continuous improvement and the results of these pilot studies constitute the basis for further research in this field
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Köhne, Claus-Henning. „Palliative Therapie des kolorektalen Karzinoms“. Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-135026.
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Die zytostatische Chemotherapie ist wesentlicher Bestandteil der palliativen Therapie von Patienten mit metastasiertem kolorektalen Karzinom. Gegenüber einer rein supportiven Behandlung verbessert eine auf 5-Fluorouracil (5-FU) basierende Chemotherapie die Lebensqualität und verlängert das Überleben der Patienten. 5- FU-Dauerinfusion moduliert mit Folinsäure ist die beste Grundlage für die Kombination mit Irinotecan oder Oxaliplatin. Randomisierte Studien zum Einsatz von Irinotecan zeigten signifikante Vorteile im Hinblick auf die Remissionsrate, das progressionsfreie Überleben und auch die mediane Überlebenszeit. Randomisierte Studien zum Einsatz von Oxaliplatin zeigten ebenfalls höhere Remissionsraten und ein verlängertes progressionsfreies Überleben ohne eine verlängerte Überlebenszeit nachweisen zu können. Heutzutage sollten alle Patienten mit einer Kombinationschemotherapie behandelt werden und im Verlauf ihrer Erkrankung, soweit möglich, alle zur Verfügung stehenden Medikamente erhalten. Nur dadurch können mediane Überlebenszeiten von über 20 Monaten erreicht werden. Der Einsatz oraler Fluoropyrimidine statt einer 5-FU-Dauerinfusion in Kombination mit Irinotecan und Oxaliplatin ist viel versprechend, jedoch Gegenstand laufender Studien. Monoklonale Antikörper gegen den EGF-Rezeptor bzw. gegen VEGF haben ebenfalls viel versprechende Ergebnisse gezeigt und werden wahrscheinlich die Behandlungsmöglichkeiten in der Zukunft wesentlich verbessernSystemic chemotherapy has a key role in the palliative treatment of patients with metastatic colorectal cancer. Compared to best supportive care, 5-fluorouracil (5-FU)-based therapy prolongs survival and improves quality of life. 5-FU continuous infusion modulated by Leukovorin (LV) is the optimal basis for a combination therapy with irinotecan or oxaliplatin. Randomized trials investigating the role of irinotecan in combination with 5-FU/LV relative to 5-FU/LV alone demonstrated a significant improvement in the response rate, progression free survival and overall survival. Randomized studies using oxaliplatin/ 5-FU/LV vs. FU/LV alone resulted in a higher response rate and longer progression-free survival while the overall survival was not significantly different. Today, all patients should receive combination treatment in first line and should be offered all active compounds during the course of their disease. Hereby, median survival times of more than 20 months are achievable. The use of oral fluoropyrimidines as a substitute of infusional 5-FU in combination with irinotecan or oxaliplatin is promising and subject of clinical trials. Monoclonal antibodies directed against the EGF-receptor or against VEGF have demonstrated interesting results and may be a treatment option in the future
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Reister, Emily. „High-Throughput Sequencing for Investigation of RNA Targets of Pt(II) Chemotherapy Drugs“. Thesis, University of Oregon, 2018. http://hdl.handle.net/1794/23758.
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Pt(II) chemotherapies, including cisplatin and oxaliplatin, have been used in cancer treatment since the 1970s, however, a full understanding of the mechanism by which these drugs function is still lacking. While the interaction between Pt(II) drugs and DNA has been extensively studied and subsequently indicted in the cellular response to Pt(II) drugs, recent data indicates non-DNA targets play important roles as well. To gain insight into the non-DNA damage-based effects induced by these drugs, MDA-MB-468 cells were treated at therapeutic concentrations of cisplatin between 30 minutes and 24 hours. Not only does this data provide insight into the complex time-dependent nature of the cellular response to cisplatin, but novel responses were also observed.
First, I describe how the expression of numerous snoRNAs decreases as early as 30 minutes post-treatment with either cisplatin or oxaliplatin, and differential expression analysis indicates this occurs before activation of the DNA damage response. Since snoRNAs are necessary components in ribosome processing, we sought to determine the role snoRNAs play in the cellular response to Pt(II) drugs. A subgroup of our identified snoRNAs direct modification of helix 69 on the 28S ribosome. Quantification of methylation of helix 69 and other locations suggests cisplatin induced changes in snoRNA expression leads to dysregulation of rRNA modification, likely altering ribosome activity. I also observe varied activation of different types of DNA damage and cell cycle arrest between 3 and 12 hours of cisplatin treatment while early expression changes show downregulation of mitochondrial genes. We also identify a number of lncRNAs previously associated with TNBC that are downregulated after cisplatin treatment. This study establishes a gene expression profile induced by cisplatin treatment of triple-negative breast cancer that demonstrates the complex interplay of multiple means of stress induction. Lastly, we establish a method for analyzing direct DNA binding targets of platinum(II) chemotherapeutics. This pilot study confirms high accumulation of platinum(II) compounds on guanine-rich DNA and suggests DNA binding of significant genes leads to changes in their RNA expression.10000-01-01
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Zamoryn, Regina. „Optimierung einer Kombinations-Chemotherapie mit Docetaxel, Gemcitabin und Oxaliplatin bei Patienten mit fortgeschrittenen soliden Tumoren“. [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=969333358.
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Sehgal, Rippa. „Binding of Oxaliplatin and its Analogs with DNA Nucleotides at Variable pH and Concentration Levels“. TopSCHOLAR®, 2016. http://digitalcommons.wku.edu/theses/1602.
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Oxaliplatin is one of the three FDA-approved platinum anticancer drugs and considered a third generation drug, discovered after the first generation drug cisplatin and second generation drug carboplatin. It is known to react with proteins and DNA nucleotides in the body. Reaction with DNA occurs primarily at guanosine residues and secondarily at adenine residues for oxaliplatin and other platinum drugs. We have previously studied oxaliplatin and an analog with additional steric hindrance in the amine ligand and found that the analog had different reactivity with methionine. Now, we have prepared oxaliplatin and its three analogs Pt(Me2dach)(ox), Pt(en)(ox) and Pt(Me4en)(ox) and have reacted each platinum compound with both guanine and adenine nucleotides at pH 4 and pH 7 at different molar ratios. These reactions have been characterized by Nuclear Magnetic Resonance (NMR) spectroscopy equipment over time to observe the formation of products and compare them on the basis of their kinetics and binding affinities. NMR has shown that even under the conditions of excess platinum, the dominant products are usually those with two nucleotides coordinated to one platinum center. Reactions are faster at pH 7 than pH 4 due to deprotonation of phosphate group. Reactions of GMP with a platinum center are faster than reaction with AMP because of the chelate formed by the oxalate ligand. The extra methyl groups on the oxaliplatin analogs do not appear to slow down the reactions with nucleotides considerably. The pH generally affects the rate but does not substantially affect the product distribution.
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Seignez, Cédric. „Etude des mécanismes d'action d'une immunothérapie par un lipide A, seul ou associé à l'oxaliplatine, dans des modèles de cancers coliques“. Thesis, Dijon, 2013. http://www.theses.fr/2013DIJOMU01/document.
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Le cancer colorectal est un problème de santé publique majeur pour lequel la recherche de nouveaux traitements est indispensable. Notre équipe a démontré l’efficacité d’une immunothérapie par un lipide A dans un modèle de cancer du colon chez le rat. Lorsque les rats sont porteurs de petites carcinomatoses, le lipide A induit la guérison de 95% des rats. L’étude des mécanismes d’action de cette immunothérapie nous a permis de montrer que l’effet antitumoral du lipide A est dépendante de la cytotoxicité induite par le granzyme B produit par les neutrophiles intratumoraux. En effet, nous avons montré que, dans le microenvironnement tumoral, les neutrophiles produisent du granzyme B et présentent un phénotype de type N2 protumorigène. Lorsque les rats sont traités par lipide A, il y a modification du phénotype des neutrophiles en type N1 antitumoral et libération du granzyme B qui induit l’apoptose des cellules tumorales. Lorsque les rats développent des tumeurs beaucoup plus volumineuses, l’efficacité du lipide A est diminuée et seul 40% des animaux sont guéris. L’injection préalable d’oxaliplatine permet alors de maintenir l’efficacité de l’immunothérapie par le lipide A. Nous avons montré que l’oxaliplatine induit la sénescence des cellules tumorales, générant ainsi un microenvironnement propice au recrutement au sein des tumeurs des neutrophiles, lesquels sont activables par l’immunothérapie subséquente. L’association de l’induction de la sénescence et de l’activation des cellules immunitaires par immunothérapie est une approche efficace et originale sur laquelle les recherches doivent se poursuivreColorectal cancer is a major public health concern in France. Resistance to standard chemotherapy requires development of novel therapeutic approaches. In the past decades, our team showed the immunotherapeutic properties of lipid A in a model of colon cancer in rats. 95% of rats bearing small carcinomas were cured following treatment by lipid A. The study of mechanisms underlying this immunotherapy allowed us to show that the antitumor effect of lipid A was dependent on cytotoxicity induced by granzyme B produced by intratumoral neutrophils. Indeed, we have shown that, in the tumor microenvironment, neutrophils produced granzyme B and had a pro-tumorigenic N2 phenotype. When rats were treated with lipid A, neutrophils shifted to an antitumor N1 phenotype and released granzyme B, thus inducing apoptosis of tumor cells. In rats bearing advanced carcinoma, the effectiveness of lipid A was reduced and only 40% of animals were cured. An injection of oxaliplatin prior to lipid A treatment allowed sustaining the effectiveness of lipid A immunotherapy. In the present study, we showed that oxaliplatin injection induced tumor cell senescence. The microenvironment produced by senescent cells enabled then the recruitment of neutrophils within tumors, subsequently activated by lipid immunotherapy.Combining the induction of tumor cells senescence and activation of immune cells by an immunotherapeutic agent constitute an original and interesting therapeutic approach, but still studies must be carrying out to better understand underlying mechanisms
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Combès, Eve. „Mise en évidence d’intéractions létales par criblage phénotypique dans le contexte de la résistance aux thérapies du cancer colorectal“. Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTT134/document.
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Aujourd’hui, les traitements du cancer colorectal métastatique ont évolué grâce à la combinaison de chimiothérapies conventionnelles à base de 5-FU, oxaliplatine et/ou Irinotécan et de thérapies ciblées dirigées contre le récepteur de l’EGF ou le VEGF. Malgré un taux de survie amélioré par la combinaison de ces drogues, la résistance innée et acquise aux traitements est une cause fréquente d'échec thérapeutique.Dans le but de découvrir de nouvelles cibles thérapeutiques nous avons effectué plusieurs criblages phénotypiques en utilisant des modèles cellulaires de résistance acquises aux chimiothérapies (oxaliplatine et irinotécan) générés au laboratoire ainsi que la lignée HCT116 qui présente une résistance innée aux thérapies anti-EGFR (cétuximab, panitumumab, Erlotinib). Le but final de ce projet étant de révéler des gènes, dont l’inhibition permet de rétablir la sensibilité à l’un de ces traitements, affichant ainsi une interaction létale avec le médicament.Une fois les kinases potentiellement impliquées dans la résistance aux thérapies du CCR identifiées, une inhibition spécifique par shRNA et/ou un inhibiteur spécifique a été effectuée afin de confirmer les potentielles cibles thérapeutiques et/ou biomarqueurs de réponse aux traitements. La cible la plus prometteuse, identifiée comme un déterminant de la résistance à l’oxaliplatine est la protéine ATR (Ataxia-telangiectasia mutated and rad3 related). Une protéine jouant un rôle clé dans la réparation de l'ADN et qui est activée en réponse à la présence d'ADN simple brin persistant (ssDNA) ou de stress réplicatif, pouvant être généré par certaines thérapies anticancéreuses.L’inhibition ATR via son inhibiteur pharmacologique VE-822 (VX-970) combinée à l’oxaliplatine a alors été étudiée par l’utilisation de tests cytotoxiques complétés par une étude d’additivité. Ainsi, nous avons démontré que l’inhibition d’ATR combinée avec l’oxaliplatine entraine une forte synergie dans la lignée HCT116-R1 à la fois en 2D et en 3D. Cet effet est également retrouvé dans d’autres lignées clonales résistantes à l’oxaliplatine (HCT116-R2, SW48-R1) ainsi que dans les lignées cellulaires à l’origine de ces dernières (HCT116, SW48). Nous avons également montré que l'effet synergique de l’oxaliplatine et du VE-822 dans la lignée HCT116-R1 s'accompagne d'une augmentation de la présence d’ADN simple brins suivie de nombreuses cassures double brins de l’ADN, d'un arrêt de la prolifération et d'une induction de l'apoptose. L'apparition de ces dommages à l'ADN est également corrélée avec l'activation de la voie ATM, de p53 et l'inhibition de l'activité CDK2. De plus, in vitro le double traitement provoque une induction des signaux moléculaires à l’origine de la mort immunogène équivalente ou bien supérieure aux traitements par l’oxaliplatine seul. Enfin, l'association d'oxaliplatine + VE-822 est également efficace in vivo, sur des souris immunodéprimées xénogreffées avec les cellules HCT116-R1 ainsi que sur des souris immunologiquement compétentes, avec un effet synergique plus élevé indiquant que la mort immunitaire (ICD) fait partie du mécanisme de cette combinaison de médicaments. En conclusion, toutes ces données confirment l’intérêt du criblage phénotypique dans la découverte de nouvelles cibles thérapeutiques en démontrant pour la première fois le rôle fonctionnel de l'ATR dans la sensibilité à l’oxaliplatineToday, treatments for metastatic colorectal cancer have evolved through the combination of conventional chemotherapy 5-FU, oxaliplatin and / or Irinotecan and targeted therapies directed against the EGF receptor or VEGF. Despite an improved survival rate through the combination of these drugs, innate and acquired resistance to treatment is a common cause of therapeutic failure.In order to discover new therapeutic targets we carried out several phenotypic screenings using cellular resistance models acquired to chemotherapies (oxaliplatin and irinotecan) generated in the laboratory as well as the HCT116 line which exhibits an innate resistance to anti-EGFR therapies (cetuximab , panitumumab, Erlotinib). The ultimate goal of this project is to reveal genes, whose inhibition restores sensitivity to one of these treatments, thus displaying a lethal interaction with the drug.Once the kinases potentially involved in resistance to CCR therapies identified, specific inhibition by shRNA and / or a specific inhibitor was performed to confirm the potential therapeutic targets and / or biomarkers for response to treatments. The most promising target, identified as a determinant of resistance to oxaliplatin is the ATR protein (Ataxia-telangiectasia mutated and rad3 related). A protein that plays a key role in DNA repair and is activated in response to the presence of persistent single stranded DNA (ssDNA) or replicative stress, which can be generated by certain anti-cancer therapies.The inhibition of ATR via its pharmacological inhibitor VE-822 (VX-970) combined with oxaliplatin was then studied by the use of cytotoxic tests supplemented by an additivity study. Thus, we demonstrated that the inhibition of ATR combined with oxaliplatin leads to a strong synergy in the HCT116-R1 cell line in both 2D and 3D. This effect is also found in other oxaliplatin resistant clonal lines (HCT116-R2, SW48-R) as well as in the cell lines originating from them (HCT116, SW48).We have also shown that the synergistic effect of oxaliplatin and VE-822 in the HCT116-R1 line is accompanied by an increase in the presence of single-stranded DNA followed by numerous double-stranded DNA breaks, stopping proliferation and inducing apoptosis. The occurrence of this damage to DNA is also correlated with activation of the ATM pathway, p53 and inhibition of CDK2 activity. Moreover, in vitro the double treatment causes an induction of the molecular signals triggering the immunogenic cell death equivalent or superior to the treatments by oxaliplatin alone.Finally, the combination of oxaliplatin + VE-822 is also effective in vivo in immunodeficient mice xenografted with HCT116-R1 cells as well as in immunologically competent mice with a higher synergistic effect indicating that immune death (ICD ) is part of the mechanism of this combination of drugs.In conclusion, all these data confirm the interest of phenotypic screening in the discovery of new therapeutic targets by demonstrating for the first time the functional role of ATR in sensitivity to oxaliplatin
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Turkington, Richard Calvin. „A systems biology approach to define pathways of oxaliplatin and 5-fluorouracil resistance in colorectal cancer“. Thesis, Queen's University Belfast, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580110.
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The discovery of underlying mechanisms of drug resistance and the development of novel agents to target these pathways is a priority for patients with advanced colorectal cancer (CRC). The aim of this study was to identify novel targets whose knock-down is important in mediating sensitivity to 5-FU and oxaliplatin in Kras wild type and mutant CRC models. Materials and Methods. Transcriptional profiling (Almac Diagnostics Colorectal Cancer Disease Specific Array'") of pre-treatment metastatic CRC liver biopsies and oxaliplatin/5-FU resistant HCTl16 cell lines followed by Pathway Analysis and Gene Set Enrichment Analysis (GSEA) were used to identify individual genes from novel drug-sensitivity pathways for incorporation into a RNAi screen. Results. We identified panels of genes whose expression is altered (acutely and basally) between sensitive and 5-FU- or oxaliplatin-resistant models. The significant pathways involved in 5-FU/oxaliplatin resistance included Cell Cycle, Focal Adhesion, Insulin and MAPK signalling. In the MAPK pathway, we found that FGFR4 silencing potently increased apoptosis in Kras wild type and mutant CRC cells, and this was further enhanced when FGFR4 siRNA was combined with 5-FU or oxaliplatin. FGFR4 inhibition completely inhibited migration of Kras mutant HCTl16 cells and we found that FGFR4 silencing resulted in strong inhibition of ST A T3 activity in Kras mutant, but not Kras wild type, CRC cells. Conclusions. This study demonstrates the utility of microarray expression data, obtained from pre-clinical and clinical samples, and analyzed by pathway and Gene Set Enrichment Analysis to identify pathways of oxaliplatin/5-FU sensitivity in CRC. In addition FGFR4 inhibition in combination with 5-FU or oxaliplatin could represent a novel treatment strategy for Kras mutant and wild type CRC tumours. We are currently investigating FGFR4 small molecule inhibitors in preclinical in vitro and in vivo models.
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Stordal, Britta Kristina. „Regrowth resistance in platinum-drug resistant small cell lung cancer cells“. Bill Walsh Cancer Research Laboratories, Royal North Shore Hospital and The University of Sydney, 2007. http://hdl.handle.net/2123/2467.
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Doctor of Philosophy (PhD)The H69CIS200 cisplatin-resistant and H69OX400 oxaliplatin-resistant cell lines developed as part of this study, are novel models of low-level platinum resistance. These resistant cell lines do not have common mechanisms of platinum resistance such as increased expression of glutathione or decreased platinum accumulation. Rather, these cell lines have alterations in their cell cycle allowing them to proliferate rapidly post drug treatment in a process known as ‘regrowth resistance’. This alteration in cell cycle control has come at the expense of DNA repair capacity. The resistant cell lines show a decrease in nucleotide excision repair and homologous recombination repair, the reverse of what is normally associated with platinum resistance. The alterations in these DNA repair pathways help signal the G1/S checkpoint to allow the cell cycle to progress despite the presence of DNA damage. The decrease in DNA repair capacity has also contributed to the development of chromosomal alterations in the resistant cell lines. Similarities in chromosomal change between the two platinum resistant cell lines have been attributed to inherent vulnerabilities in the parental H69 cells rather than part of the mechanism of resistance. The H69CIS200 and H69OX400 resistant cells are cross-resistant to both cisplatin and oxaliplatin. This demonstrates that oxaliplatin does not have increased activity in low-level cisplatin-resistant cancer. Oxaliplatin resistance also developed more rapidly than cisplatin resistance suggesting that oxaliplatin may be less effective than cisplatin in the treatment of SCLC. The resistant cell lines have also become hypersensitive to taxol but show no alterations in the expression, polymerisation or morphology of tubulin. Rather, the PI3K/Akt/mTOR pathway is involved in both platinum resistance and taxol sensitivity as both are reversed with rapamycin treatment. mTOR is also phosphorylated in the resistant cell lines indicating that platinum resistance is associated with an increase in activity of this pathway. The mechanism of regrowth resistance in the platinum-resistant H69CIS200 and H69OX400 cells is a combination of activation of PI3K/Akt/mTOR signalling and alterations in control of the G1/S cell cycle checkpoint. However, more work remains to determine which factors in these pathways are governing this novel mechanism of platinum resistance.
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Nicolay, N. H. „The role of DNA polymerase eta in determining cellular responses to chemo-radiation treatment“. Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:73cef89c-319d-4a14-a3a6-93e8b8dd186a.
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DNA polymerase η (pol η), a crucial component of the cellular translesion synthesis pathway, allows cells to bypass and thereby temporarily tolerate DNA damage. Inherited deficiency of pol η, as reported in the variant form of xeroderma pigmentosum, predisposes to UV light-induced skin cancers. To date, pol η is the only DNA polymerase shown to exhibit a causal link to the formation of cancers in humans. However, the role of pol η in the cellular response to forms of DNA damage other than UV-induced lesions is largely unknown. In the first part of this thesis, it is shown that cells deficient in pol η are resistant to ionising radiation. Deficiency in the polymerase was associated with accumulation of cells in S phase of the cell cycle. Cells deficient in pol η demonstrated increased homologous recombination-directed repair of DNA double-strand breaks created by ionising radiation, and depletion of the homologous recombination protein X-ray repair cross-complementing protein 3 (XRCC3), abrogated the radioresistance observed in pol η-deficient cells compared to pol η-complemented cells. These findings suggest that homologous recombination mediates S phase-dependent radioresistance associated with pol η-deficiency. In the second part of this thesis, it is shown that pol η-deficient cells have increased sensitivity to the chemotherapeutic compound, oxaliplatin, compared to pol η-deficient expressing cells, but not to the drug 5-fluorouracil that is usually administered in combination with oxaliplatin in the clinical setting. Despite the importance of pol η for cellular survival following exposure to oxaliplatin, the drug did not upregulate the enzyme after either short-term or long-term exposure. Inhibition of pol η activity by siRNA-mediated knockdown of the protein sensitised cells to oxaliplatin treatment, and partially reversed acquired resistance in oxaliplatin-resistant tumour cell lines. These data suggest that pol η is an interesting target whose function can potentially be interfered with to optimise oxaliplatin-based chemotherapy. In the third part of this thesis, clinical samples obtained from oesophageal cancer patients before and after treatment with oxaliplatin-containing chemotherapy were analysed for POLH mRNA levels encoding pol η protein. Malignant tissue specimens obtained before treatment demonstrated a significantly higher level of POLH mRNA than matched normal oesophageal tissue samples. Contrary to the preclinical data, high POLH mRNA expression before therapy was shown to correlate with increased overall and disease-free survival of the patient cohort in the clinical trial. Additionally, patients with high POLH mRNA-expressing cancers had better therapeutic responses (measured by PET-CT) to oxaliplatin-based treatment than those with low levels. These data suggest that POLH mRNA expression should be tested as a biomarker to predict survival and therapeutic responses in oesophageal cancer patients treated with oxaliplatin-containing chemotherapy.
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Köhne, Claus-Henning. „Palliative Therapie des kolorektalen Karzinoms“. Karger, 2003. https://tud.qucosa.de/id/qucosa%3A27613.
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Die zytostatische Chemotherapie ist wesentlicher Bestandteil der palliativen Therapie von Patienten mit metastasiertem kolorektalen Karzinom. Gegenüber einer rein supportiven Behandlung verbessert eine auf 5-Fluorouracil (5-FU) basierende Chemotherapie die Lebensqualität und verlängert das Überleben der Patienten. 5- FU-Dauerinfusion moduliert mit Folinsäure ist die beste Grundlage für die Kombination mit Irinotecan oder Oxaliplatin. Randomisierte Studien zum Einsatz von Irinotecan zeigten signifikante Vorteile im Hinblick auf die Remissionsrate, das progressionsfreie Überleben und auch die mediane Überlebenszeit. Randomisierte Studien zum Einsatz von Oxaliplatin zeigten ebenfalls höhere Remissionsraten und ein verlängertes progressionsfreies Überleben ohne eine verlängerte Überlebenszeit nachweisen zu können. Heutzutage sollten alle Patienten mit einer Kombinationschemotherapie behandelt werden und im Verlauf ihrer Erkrankung, soweit möglich, alle zur Verfügung stehenden Medikamente erhalten. Nur dadurch können mediane Überlebenszeiten von über 20 Monaten erreicht werden. Der Einsatz oraler Fluoropyrimidine statt einer 5-FU-Dauerinfusion in Kombination mit Irinotecan und Oxaliplatin ist viel versprechend, jedoch Gegenstand laufender Studien. Monoklonale Antikörper gegen den EGF-Rezeptor bzw. gegen VEGF haben ebenfalls viel versprechende Ergebnisse gezeigt und werden wahrscheinlich die Behandlungsmöglichkeiten in der Zukunft wesentlich verbessern.Systemic chemotherapy has a key role in the palliative treatment of patients with metastatic colorectal cancer. Compared to best supportive care, 5-fluorouracil (5-FU)-based therapy prolongs survival and improves quality of life. 5-FU continuous infusion modulated by Leukovorin (LV) is the optimal basis for a combination therapy with irinotecan or oxaliplatin. Randomized trials investigating the role of irinotecan in combination with 5-FU/LV relative to 5-FU/LV alone demonstrated a significant improvement in the response rate, progression free survival and overall survival. Randomized studies using oxaliplatin/ 5-FU/LV vs. FU/LV alone resulted in a higher response rate and longer progression-free survival while the overall survival was not significantly different. Today, all patients should receive combination treatment in first line and should be offered all active compounds during the course of their disease. Hereby, median survival times of more than 20 months are achievable. The use of oral fluoropyrimidines as a substitute of infusional 5-FU in combination with irinotecan or oxaliplatin is promising and subject of clinical trials. Monoclonal antibodies directed against the EGF-receptor or against VEGF have demonstrated interesting results and may be a treatment option in the future.
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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Ip, Virginia. „The expression of copper transporters in rat dorsal root ganglion neurons and its role in oxaliplatin neurotoxicity“. Thesis, University of Auckland, 2011. http://hdl.handle.net/2292/18999.
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Oxaliplatin is a platinum-based anticancer agent used for the treatment of colorectal cancer. Oxaliplatin chemotherapy is associated with peripheral neuropathy and dorsal root ganglia neurons are the putative target, however the mechanism of toxicity is currently unknown. Recent evidence suggests that copper transporters may be implemented in the transport and neurotoxicity of platinum drugs. We hypothesis that platinum drugs induce neurotoxicity by mechanisms involving copper transporters. To examine the mechanisms by which dorsal root ganglia neurons are damaged by oxaliplatin, the mRNA and protein expressions of copper transporters were investigated in healthy and oxaliplatin treated adult rats. Adult rat dorsal root ganglion tissue exhibited a specific pattern of expression of copper transporters with distinct subsets of neurons intensely expressing either ATP7A or CTR1, but not both or ATP7B. Neurons expressing the copper influx transporter, CTR1, were more susceptible to oxaliplatin-induced neurotoxicity compared to neurons expressing the copper efflux transporter ATP7A. Based on the abovementioned findings, a series of compounds used for the treatment of Menkes and Wilson's disease were tested in a rat model of oxaliplatin-induced neurotoxicity. Copper histidine (0.02-20 mg/kg) and ammonium tetrathiomolybdate (1 - 30 mg/kg) showed initial protection in a pilot study but did not significantly reduce the neurotoxicity of oxaliplatin, based on DRG morphometric changes, in a subsequent definitive study. Copper treatment did not increase the systemic copper level or reduce the neurotoxicity of oxaliplatin in the current in vivo rat model. Primary cultures of dorsal root ganglion neurons were employed to investigate the expressions of copper transporters in untreated and in oxaliplatin treated neurons. It was found that CTR1 and ATP7A were expressed in distinct sub-population of cultured rat DRG neurons. Oxaliplatin caused atrophy in the neurons expressing CTR1 and a loss of membrane staining frequency without altering the number of neurons. Neurons expressing ATP7A was not affected by oxaliplatin treatment.
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Bednarsch, Jan [Verfasser]. „Einsatz des 13C-Leberfunktionstests LiMAx im Kontext Oxaliplatin-basierter Chemotherapie und extrakorporaler Membranoxygenierung sowie Allgemeinanästhesie / Jan Bednarsch“. Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2016. http://d-nb.info/1119803071/34.
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Bezu, Lucillia. „Mort cellulaire immunogène : du stress du reticulum endoplasmique à l'exposition de la calréticuline“. Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLS246.
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Les traitements actuels anticancéreux ont une action cytotoxique directe sur les cellules tumorales mais également sur les cellules saines des systèmes immunitaires et hématopoïétiques. De plus, ces traitements ont l’incapacité de stimuler le système immunitaire et de prévenir les récidives. Cependant, certains agents tels que les anthracyclines, la radiothérapie ou encore la thérapie photodynamique ont la capacité d’induire une mort cellulaire dite immunogène. Durant cette modalité, l’exposition à la surface des cellules tumorales mourantes d’une protéine chaperonne du reticulum endoplasmique (RE), la calréticuline (CALR), est une étape essentielle et caractéristique de l’immunogénicité ainsi que la libération d’HMGB1, l’autophagie et la sécrétion d’ATP. Des données issues de la littérature prouvent que les anthracyclines sont également capables d’activer des marqueurs du stress du RE. Notre travail a consisté à étudier les liens moléculaires entre le stress du RE et les marqueurs de la mort cellulaire immunogène. Grâce à un criblage à haut débit, nous avons déterminé que les drogues dites immunogènes activaient la phosphorylation d’eIF2α (eukaryotic initiation factor 2 alpha) et qu’il existait une corrélation forte avec l’exposition de la CALR (R score 0,73 ; p<0,01). De manière surprenante, ces agents échouent à activer la voie de signalisation sous-jacente ainsi que les deux autres voies du stress du RE médiées par ATF6 (activating transcription factor 6) et XBP1s (spliced X-box binding protein 1). Par ailleurs, une anthracycline appelée mitoxantrone inhibe activement les trois voies du stress du RE en co-traitement avec un inducteur du stress du RE et inhibiteur de la N-glycosylation: la tunicamycine. Ces données in vitro ont également été validées dans un modèle in vivo de souris immunodéficientes xénogreffées. De plus, grâce à un algorithme reliant les propriétés physico-chimiques des drogues anti-cancéreuses avec leurs capacités à induire les marqueurs de mort cellulaire immunogène suivants: P-eIF2α, CALR, HMGB1, granules de stress et autophagie, un score prédictif d’immunogénicité a pu être déterminé. Nous devrons déterminer dans le futur comment utiliser ce score comme marqueur prédictif d’une réponse immunogène au cours des traitements cliniquesConventional anticancer chemotherapies display a high degree of toxicity with certain specificity for tumor cells. However most of these approaches fail to activate immune system-related bystander effects and thus do often fail to prevent from recurrence. Despite these premises, certain anticancer treatments (including anthracycline-based chemotherapy, radiotherapy and photodynamic therapy) have the ability to induce an immunogenic cell death (ICD) modality. The exposure of calreticulin (CALR) during the course of ICD is quintessential for the transfer of tumor antigen from dying tumors to dendritic cells of the immune system as well as translocation of high mobility group box 1 (HMGB1), autophagy and ATP secretion. Previous studies have shown that certain anticancer agents including anthracylins are able to activate markers of endoplasmic reticulum stress (ER stress). Here we investigated the molecular mechanisms that link ER stress responses with hallmarks of ICD. In a drug screening approach, we showed that ICD-inducing drugs triggered the phosphorylation of the eukaryotic initiation factor 2 alpha (P-eIF2α) and that this correlated with CALR exposure (R score 0.73, p<0.01). Surprisingly though the agents failed to induce downstream ER stress pathways including the transcriptional activation of activating transcription factor 4 (ATF4), the alternative splicing of X-box binding protein 1 (XBP1s) mRNA and the proteolytic cleavage of activating transcription factor 6 (ATF6). In addition, we found that mitoxantrone actively inhibited all three arms of the unfolded protein response, when co-administered with the inhibitor of N-linked glycosylation tunicamycin, whereas tunicamycin alone triggered all arms of ER-stress. These findings were validated in vivo in immunodeficient animals xenografted with biosensors for ER-stress responses. Moreover, using a machine learning approach that integrates physicochemical properties of oncologic drugs with their ability to elicit immunogenic hallmarks including the phosphorylation of eIF2α, the exposure of CALR, the translocation of HMGB1, the formation of stress granules and the induction of autophagy we established an in silico approach for ICD prediction. For the future, we further aim to investigate the possibility to use these score comprising P-eIF2α and its downstream consequences as biomarker for immunogenic responses during anticancer treatment in patients
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Muniz, Viviane Palhares. „The role of Parf, a novel partner of ARF, in pancreatic ductal adenocarcinoma and in ARF signaling“. Diss., University of Iowa, 2012. https://ir.uiowa.edu/etd/3503.
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Pancreatic ductal adenocarcinoma (PDAC) is an incurable, highly metastatic cancer resistant to current treatments. A better understanding of the genetic basis of PDAC progression is urgently needed to improve treatment options. The ARF tumor suppressor is inactivated in ~45% of PDAC. My thesis lab identified a new, uncharacterized ARF binding protein, Partner of ARF isoform 1A (Parf-1A). This thesis explores the hypothesis that Parf-1A plays an important role in PDAC and ARF tumor suppressor signaling
Initial studies sought to develop a novel mouse xenograft model of PDAC metastasis that would expedite testing of putative PDAC genes. Human PDAC cell lines stably expressing luciferase were generated and introduced by intracardiac injection into immunodeficient mice to model hematogenous dissemination of cancer cells. Tumor development was monitored non-invasively by bioluminescence imaging and found to recapitulate PDAC tumor formation and metastatic distribution. The model was validated by the ability of ARF to suppress PDAC cancer cell migration in vitro and reduce tumor cell colonization in vivo; establishing a new bioluminescent mouse model for rapidly assessing the significance of suspected PDAC genes.
Using human PDAC cell lines and tumor specimens, we investigated the role and significance of Parf-1A to PDAC. RNAi analyses demonstrated Parf-1A is required for PDAC cell survival, proliferation and resistance to the PDAC therapeutic, oxaliplatin. PDAC cells are ARF-null; therefore these tumor promoting activities of Parf-1A were independent of ARF. Notably, immunohistochemical analyses of Parf-1A in human PDAC tumors showed Parf-1A expression is a prognostic marker of poor survival in PDAC patients. These data suggest Parf-1A is a novel biomarker of PDAC and potential target for anticancer therapy.
Other studies tested how Parf-1A influenced ARF signaling. Parf-1A depletion and overexpression showed it inhibits ARF anti-proliferative activity by mobilizing ARF from the nucleus (where it is functional) into the cytoplasm. These data show Parf-1A is a new inhibitor of ARF. Considered with findings that Parf-1A can act independent of ARF to promote PDAC tumorigenesis, such results suggest Parf-1A is a novel oncoprotein that acts through multiple pathways to facilitate tumorigenesis. Thus, Parf-1A may have broad relevance to many types of human cancers.
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Novotná, Jaroslava [Verfasser], und Dennis [Akademischer Betreuer] Nowak. „Exposition von OP-Personal gegenüber Cis/Oxaliplatin bei Operationen nach dem HIPEC-Verfahren / Jaroslava Novotna. Betreuer: Dennis Nowak“. München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2012. http://d-nb.info/1031379452/34.
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Chocry, Mathieu. „Etude des mécanismes de résistance à l'oxaliplatine dans le cancer colorectal : rôle des voies NOX1/Calpaïnes“. Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0667.
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Le cancer colorectal est un cancer majeur en termes de fréquence et de mortalité. Il s’agit de la deuxième cause de décès par cancer, avec 17 500 décès en France en 2011. Le traitement des stades avancés repose sur différentes molécules anti-cancéreuses telles que l’oxaliplatine. Cependant le développement de résistances entraine des échecs thérapeutiques expliquant le faible taux de survie observé. Il est donc crucial d’identifier les mécanismes de résistance et ses acteurs et de découvrir de nouvelles pistes de traitements.Dans un premier temps, nous nous sommes donc intéressés aux rôles joués par les calpaïnes et NOX1 dans le développement de la résistance à l’oxaliplatine en étudiant des cellules tumorales colorectales résistantes à cette drogue. Ce qui nous a permis d'identifier une voie de signalisation impliquée dans la résistance à cette chimiothérapie.Dans un second temps nous nous sommes intéressés à étudier la réversion de cette résistance à l’oxaliplatine. En criblant différentes chimiothérapies ce qui a permis de mettre en évidence une inversion du statut résistant/sensible dans nos cellules sélectionnées.La première partie de nos données met en évidence de nouvelles régulations de Nox1 qui diffèrent en fonction de la sensibilité des cellules à l’oxaliplatine. Nos résultats montrent aussi que p38 MAPK pourrait être une cible thérapeutique de choix. Dans la deuxième partie nous avons identifié un nouveau traitement permettant l'induction de l'apoptose dans nos cellules résistantes. Ainsi la gemcitabine pourrait être une solution pour traiter les patients ne répondant pas ou plus aux protocoles basés sur l’oxaliplatineColorectal cancer is a major cancer in terms of frequency and mortality. This is the second leading cause of cancer death, with 17,500 deaths in France in 2011. The treatment of advanced stages is based on different chemotherapeuties including oxaliplatin. However, the development of resistance leads to therapeutic failures explaining the low survival rate. It is therefore crucial to identify the mechanisms of resistance and the actors involved and to discover new therapeutic approaches. We first investigated the role played by calpains and NOX1 in the development of resistance to oxaliplatin, studying oxaliplatin-resistant colorectal tumor cells. This allowed us to identify a signaling pathway involved in resistance to this chemotherapy.Secondly, we have studied the reversion of this resistance to oxaliplatin. A screening of different chemotherapies revealed a reversal of the resistant / sensitive status in our selected cells In the first part, our data highlight novel Nox1 regulations which differ according to the sensitivity of the cells to oxaliplatin. Our results also show that p38 MAPK could be a therapeutic target for treating colorectal cancers resistant to oxaliplatin. In the second part, we have identified a new treatment to induce apoptosis in our resistant cells. Indeed, gemcitabine may be a solution to treat patients who do not respond to oxaliplatin-based protocols
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Ferrier, Jeremy. „Douleurs neuropathiques induites par l'oxaliplatine. Physiopathologie et approches thérapeutiques“. Thesis, Clermont-Ferrand 1, 2013. http://www.theses.fr/2013CLF1PP06/document.
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L’oxaliplatine, anticancéreux utilisé pour le traitement du cancer colorectal, est responsable d’une neurotoxicité périphérique dose-limitante affectant une grande majorité de patients. La neurotoxicité de l’oxaliplatine se présente sous deux formes : une forme immédiate, se traduisant par des paresthésies transitoires, et une forme retardée et cumulative, caractérisée par l’apparition d’une neuropathie périphérique douloureuse fortement invalidante. A l’heure actuelle, la prise en charge des douleurs neuropathiques est souvent incomplète, principalement à cause du manque de traitements efficaces et bien tolérés. Dans ce contexte, il existe un réel besoin d’innovation thérapeutique pour améliorer le traitement de ces neuropathies, nécessitant au préalable une meilleure compréhension de leur physiopathologie. La première partie de ce travail porte sur l’évaluation de l’effet d’une alimentation sans polyamines sur l’apparition et la chronicisation de la neurotoxicité de l’oxaliplatine chez le rat. En effet, en modulant positivement la sous-unité NR2B des récepteurs NMDA, les polyamines alimentaires pourraient faciliter la sensibilisation douloureuse. Un régime sans polyamines a permis de prévenir l’hypersensibilité thermique et mécanique induite par l’oxaliplatine. Bien que ces symptômes nociceptifs ne soient pas associés à une augmentation de l’expression de la sous-unité NR2B au niveau spinal, l’ifenprodil (antagoniste NR2B spécifique) permet d’en diminuer l’intensité de manière dose-dépendante. Enfin, une étude métabolomique réalisée par spectroscopie RMN du proton a montré que le régime sans polyamines permettait de réguler la neurotransmission excitatrice (glutamate) au niveau de la corne dorsale de la moelle épinière des animaux, expliquant ainsi son effet antalgique. Dans un deuxième temps, nous nous sommes intéressés aux mécanismes supraspinaux impliqués dans la neuropathie chronique induite par l’oxaliplatine, à l’aide d’une approche métabolomique par 1 H-RMN HRMAS. Cette étude a révélé d’importantes modifications métaboliques cérébrales chez les animaux traités par oxaliplatine, notamment une augmentation de la choline dans le cortex insulaire postérieur corrélée de manière significative aux seuils douloureux. Une analyse transcriptomique et pharmacologique a permis de mettre en évidence une implication de la neurotransmission cholinergique dans cette structure. Le ciblage pharmacologique de cette neurotransmission pourrait représenter une stratégie potentiellement intéressante pour le développement de nouveaux traitements antalgiques. L’ensemble de ces résultats expérimentaux a permis l’identification de nouvelles pistes pour la compréhension et le traitement des douleurs neuropathiques chimio-induites. Dans une perspective de recherche translationnelle, ces deux approches précliniques sont en cours de transposition dans des protocoles de recherche clinique. Un essai clinique de phase II (NEUROXAPOL, NCT01775449) a débuté afin de confirmer l’intérêt d’un régime appauvri en polyamines chez des patients recevant une chimiothérapie à base d’oxaliplatine. Une seconde étude clinique (INSULOX) est actuellement en cours de préparation au CHU de Clermont-Ferrand afin de mesurer par IRM les concentrations en choline dans l’insula de patients souffrant de douleurs neuropathiques induites par oxaliplatineOxaliplatin, an anticancer drug used for the treatment of colorectal cancer, is responsible for a dose-limiting peripheral neurotoxicity in the majority of treated patients. This neurotoxicity appears with two components: a rapid-onset acute neurotoxicity manifesting as transient paresthesias and cold-induced dysesthesias; and a late-onset cumulative neurotoxicity characterized by the development of a painful chronic neuropathy. To date, the management of chemotherapy- induced neuropathic pain is still challenging because of the lack of effective treatments. In this context, a better understanding of the pathophysiological mechanisms underlying this neurotoxicity could lead to the identification of new therapeutic targets. Firstly, we aimed to assess the preventive effect of a polyamine deficient diet on the development of oxaliplatin-induced acute neurotoxicity. Exogenous polyamines, by positively modulating spinal NR2B-containing NMDA receptors, could facilitate pain sensitization. This study has shown that a polyamine deficient diet for 7 days totally prevented oxaliplatin-induced acute cold and mechanical hypersensitivity in rats. Although we observed no change in spinal NR2B expression or phosphorylation, intrathecal ifenprodil (a specific NR2B antagonist) reduced oxaliplatin-induced allodynia in a dose-dependent manner. Finally, proton NMR spectroscopy- based metabolomic analysis has revealed a regulation of spinal glutamate neurotransmission as the most likely mechanism underlying the preventive effect of the diet. Secondly, the metabolic variations associated with oxaliplatin-induced chronic neuropathy were assessed at the supraspinal level using a 1 H-NMR HRMAS-based metabolomic approach. Among the neurochemical changes evidenced in this study, we observed a significant increase in choline within the posterior insular cortex, significantly correlated with the mechanical pain thresholds. A transcriptomic and pharmacological approach have revealed an implication of cholinergic neurotransmission in this brain area. Targeting the cholinergic system using centrally active muscarinic agents could represent an interesting strategy for the treatment of oxaliplatin- induced neuropathic pain. These experimental results led to the identification of new molecular targets for the comprehension and the treatment of chemotherapy-associated painful neuropathy. In a translational approach, these preclinical data will be extended to the clinical setting. A phase II clinical trial (NEUROXAPOL, NCT01775449) is undergoing to confirm the therapeutic interest of a polyamine free diet in patients receiving oxaliplatin. A second clinical project (INSULOX) aiming at assessing the choline concentrations in the insula of patients suffering from oxaliplatin-induced neuropathy is in preparation
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Teng, Christina Sian Hwa. „Chemotherapy-induced peripheral neuropathy: Novel approaches to assessment, prevention and treatment“. Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/29993.
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Chemotherapy-induced peripheral neuropathy (CIPN) is a common and often persistent problem of cancer treatment, with no proven preventative and few effective treatment strategies. Consensus is lacking about the appropriate tools to diagnose and monitor CIPN. With improved survival outcomes, it is increasingly important to understand the impact of CIPN and improve its management.
The research in this thesis was conducted to characterise challenges that CIPN presents to patients and clinicians, and explore potential solutions. The thesis addresses the prevalence, assessment, and impact of CIPN at several stages of cancer survivorship. Early thesis chapters focus on better defining the problem of CIPN in published literature and real-world populations. Later chapters of the thesis transition into the exploration of innovative strategies to improve the function and quality of life of cancer survivors at risk of, or currently affected by, CIPN.
A systematic review and meta-analysis of the prevalence of long term CIPN following adjuvant oxaliplatin demonstrated rates of 58%, 45%, 32% and 24% at 6, 12, 24 and 36 months respectively. The evaluation of CIPN was heterogenous, highlighting the need for a uniform assessment strategy.
In a cohort of ‘real world’ colorectal cancer survivors (n=233, 55% who received adjuvant oxaliplatin), CIPN was more frequent than reported in clinical trials. Prevalence of CIPN symptoms was 57%, (74% of oxaliplatin recipients) at mean 6 months after chemotherapy. CIPN was associated with presence of pain and lower quality of life.
In a longitudinal study exploring virtual reality (VR) to assess balance as a surrogate measure for CIPN (n=34), patient-reported CIPN was a more sensitive indicator than the VR tool. Balance impairment measured by VR was associated with falls, indicating it may be a useful objective functional measure of global falls risk.
Ibudilast, an oral selective phosphodiesterase inhibitor, was co-administered with oxaliplatin-containing chemotherapy in a before vs after pilot study to evaluate its ability to prevent CIPN in patients with gastrointestinal cancer (n=16). Stable or improved neuropathy was suggested following a single cycle, with no apparent pharmacokinetic interactions or serious toxicities.
Laser photobiomodulation for CIPN was evaluated in a randomised non-comparative phase 2 trial (n=44). Both control and intervention groups demonstrated CIPN improvement post intervention. Sustained improvement was observed 6 weeks post intervention in the laser group alone, suggesting a latent benefit to this modality as a CIPN treatment warranting further study.
In conclusion, this work provides insights into the differences between CIPN in trial and real-world populations, with a focus on adjuvant colorectal cancer. It furthers the understanding that CIPN is complex to assess, suggesting a combination of patient-reported and objective measures to be the most appropriate strategy. While innovative modalities to prevent and treat CIPN show early promise in the work of this thesis, further validation and larger studies are required to evaluate their benefit; one of which is already in progress.
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Stieg, Mareike. „Chemoimmuntherapie des Pankreaskarzinoms: Kombination aus bifunktioneller 5'-Triphosphat-modifizierter siRNA gegen TGFβ1 und den Chemotherapeutika Gemcitabin, Oxaliplatin und 5-Fluoruracil“. Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-172083.
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Michels, Beate [Verfasser]. „Oxaliplatin in der perioperativen, multimodalen Behandlung (präoperative Chemoradiotherapie, TME-Chirurgie und postoperative Chemotherapie) des Rektumkarzinoms – eine monozentrische Analyse – / Beate Michels“. Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2021. http://d-nb.info/1227707266/34.
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Timme, Cindy R. „Drug Resistance Mechanisms to Gamma-secretase Inhibitors in Human Colon Cancer Cells“. Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4954.
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Colorectal cancer is the third leading cause of cancer-related mortality. Much progress has been achieved in combating this disease with surgical resection and chemotherapy in combination with targeted drugs. However, most metastatic patients develop drug resistance so new modalities of treatment are needed.
Notch signaling plays a vital role in intestinal homeostasis, self-renewal, and cell fate decisions during post-development and is activated in colorectal adenocarcinomas. Under debate is its role in carcinomas and metastatic disease. In theory, blocking Notch activation using gamma-secretase inhibitors (GSIs) may show efficacy alone or in combination with chemotherapy in the treatment of colon cancer.
In Chapter Three, we tested the capacity for GSIs to synergize with oxaliplatin in colon cancer cell lines and evaluated the underlying molecular mechanisms. GSI alone had no effect on colon cancer cell lines. Surprisingly, we show that GSIs blocked oxaliplatin-induced apoptosis through increased protein levels of the anti-apoptotic Bcl-2 proteins Mcl-1 and/or Bcl-xL. Restoration of apoptosis was achieved by blocking Mcl-1 and/or Bcl-xL with obatoclax (an anti-apoptotic Bcl-2 agonist) or siRNA. An unexpected result was the induction of cell death with the combination of GSI and obatoclax.
In Chapter Four, we examined the mechanism of GSI + obatoclax-mediated cell death. We found that apoptosis played a minimal role. Rather, we identified blockage of cytoprotective autophagy played a causative role. Interestingly, we also saw autophagy induction in GSI-treated cells, which could explain the insensitivity of colon cancer cells to GSI. When autophagy was blocked in GSI-treated cells, cells became sensitive to GSI and cell death was elicited. The mechanism by which induction of autophagy occurs in GSI- treated cells is an area for further research.
Overall, our work questions the validity of the use of GSIs in the treatment of colorectal cancers. We show that GSIs may block apoptosis and induce cytoprotective autophagy simultaneously, resulting in increased drug resistance and cellular survival. Whether these two cellular survival processes occurs in patients needs to be examined before GSIs can be utilized in a clinical setting. If so, these two hurdles must be overcome.
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Marquardt, Goentje-Gesine [Verfasser], und Dorothee [Akademischer Betreuer] Dartsch. „Vergleich der Verträglichkeit von Irinotecan und Oxaliplatin zwischen älteren und jüngeren Patienten mit kolorektalem Karzinom / Goentje-Gesine Marquardt. Betreuer: Dorothee Dartsch“. Hamburg : Staats- und Universitätsbibliothek Hamburg, 2011. http://d-nb.info/1020458690/34.
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Lleshi, Arben. „Studio prospettico sul trattamento di prima linea nel cancro del colon-retto metastatico degli anziani“. Doctoral thesis, Università di Catania, 2012. http://hdl.handle.net/10761/948.
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Malieno, Paula Braz. „Avaliação sensitiva de doentes com câncer colorretal tratados com oxaliplatina“. Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/5/5138/tde-05012017-163025/.
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A avaliação sensitiva de pacientes tratados com oxaliplatina tem se tornado objeto de estudo, pelo fato deste medicamento causar como efeito colateral, uma neuropatia periférica com características sensitivas, imediatamente após início da infusão. Sintomas que causam restrições nas atividades de vida diárias e na qualidade de vida do paciente durante o tratamento. Para uma melhor compreensão do mecanismo das alterações sensitivas, atualmente tem se utilizado o teste quantitativo da sensibilidade (TQS), que através da mensuração quantitativa dos limiares de detecção aos estímulos quente, frio e de vibração, nos concede um perfil para melhor relacionar com as possibilidades de manejo ou tratamento. Neste estudo propomos uma análise da através do TQS e de instrumentos que quantificam e qualificam a neuropatia, a dor neuropática e suas características. Objetivos: Descrever de forma prospectiva as alterações de sensibilidade exteroceptiva somática causadas pelo uso da oxaliplatina em doentes com câncer colorretal. Métodos: Foram incluídos 110 doentes (média 55 anos) com câncer colorretal que realizaram tratamento antineoplásico com oxaliplatina por seis meses, e foram avaliados por mais seis após a quimioterapia. Os pacientes realizaram avaliação sensitiva com TQS e responderam questionário sócio demográfico e questionários específicos para dor e neuropatia na visita basal (VB), ao término da quimioterapia (VT) e novamente após 6 meses de seguimento (VS). Resultados: Os questionários de dor e neuropatia mostraram seu início e as suas características, na qual foi evidente a dor com características neuropáticas na visita término do tratamento em 21,7% dos participantes manifestada pela dormência, choque elétrico, alfinetadas e agulhadas e a sensibilidade ao frio. As principais alterações demonstradas pelo TQS foram: nos limiares de detecção mecânica; aumento dos limiares dolorosos térmicos; diminuição da hiperalgesia mecânica; diminuição do limiar de detecção vibratória na mão e aumento no pé. O TQS indicou alterações entre os participantes do estudo e o grupo de voluntários saudáveis em algum momento das avaliações. Conclusão: Os pacientes com câncer colorretal submetidos ao tratamento com oxaliplatina cursam com dor com características neuropáticas que interferem em suas atividades diárias. O TQS caracterizou as principais alterações relacionadas ao início do tratamento, término do tratamento e durante o seguimento. As comparações com voluntários saudáveis sugerem que a presença da neoplasia e outras comorbidades são capazes de causarem alterações no TQSSensory evaluation of patients treated with oxaliplatin has become an object of study, because this medication cause as a side effect, peripheral neuropathy with sensory characteristics, immediately after start of infusion. Symptoms that cause restrictions in daily activities and in the patient\'s quality of life during treatment. For a better understanding of the mechanism of sensory changes, currently it has used quantitative sensitivity testing (QST). That by the quantitative measurement of thresholds to warm stimuli, cold and vibration, gives us a profile to better relate to the possibilities of management or treatment. In this study we propose an analysis by QST and tools to quantify and qualify neuropathy, neuropathic pain and its features. Objectives: To describe prospectively the somatic exteroceptive sensitivity changes caused by the use of oxaliplatin in patients with colorectal cancer. Methods: We included 110 patients (mean 55 years) with colorectal cancer who underwent anticancer treatment with oxaliplatin for six months and were evaluated for six after chemotherapy. Patients underwent sensory evaluation with QST and answered sociodemographic questionnaire and specific questionnaires for pain and neuropathy at baseline, at the end of chemotherapy (visit six months) and again after 6 months of follow-up (visit twelve months). The instruments used were reduced McGill Pain Questionnaire (MPQ), Inventory symptoms of neuropathic pain (ISDN), Brief Pain Inventory (BPI-Brief Pain Inventory) Questionnaire neuropathic pain 4 (DN4), hospital scale of anxiety and depression (HADS). Results: The pain questionnaires and neuropathy showed its beginning and its characteristics, which was evident pain with neuropathic characteristics in the end visit of treatment in 21.7% of participants manifested by numbness, electric shock, pins and needles and sensitivity to cold. The main changes demonstrated by QST were in mechanical thresholds; painful increase in thermal thresholds; reduction in mechanical hyperalgesia; reduction of vibration detection limit for the hand and foot increases. The QST indicated changes between the study participants and the group of healthy volunteers at some point of the evaluations. Conclusion: Patients with colorectal cancer undergoing treatment with oxaliplatin occur with pain with neuropathic characteristics that interfere with their daily activities. QST characterized the major changes related to the start of treatment, end of treatment and during follow-up. Comparisons with healthy volunteers suggest that the presence of neoplasia and other comorbid conditions are capable of causing changes in the QST
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Duran, M. Ortega. „Investigation of mechanisms of drug resistance in colorectal cancer : a proteomic and pharmacological study using newly developed drug-resistant human cell line subclones“. Thesis, University of Bradford, 2017. http://hdl.handle.net/10454/15064.
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Despite therapeutic advances, colorectal cancer still has a 45% mortality rate, and one of the most crucial problems is the development of acquired resistance to treatment with anticancer drugs. Thus the aims of this project are to develop drug-resistant colon cancer cell lines in order to identify mechanisms of resistance for the most commonly drugs used in colorectal cancer: 5-fluorouracil, oxaliplatin, and irinotecan. Following evaluation of drug sensitivity to these agents in an initial panel of eight colorectal cancer cell lines, 3 lines (DLD-1, KM-12 and HT-29) were selected for the development of 5-FU (3 lines), oxaliplatin (2) and irinotecan (1) resistant sublines by continuous drug exposure, with resistance confirmed using the MTT assay. Consistently resistant sublines were subject to a „stable isotope labelling with amino acids in cell culture‟ (SILAC) approach and a MudPIT proteomics strategy, employing 2D LC and Orbitrap Fusion mass spectrometric analysis, to identify novel predictive biomarkers for resistance. An average of 3622 proteins was quantified for each resistant and parent cell line pair, with on average 60-70 proteins up-regulated and 60-70 down-regulated in the drug resistant sublines. The validity of this approach was further confirmed using immunodetection techniques. These studies have provided candidate proteins which can be assessed for their value as predictive biomarkers, or as therapeutic targets for the modulation of acquired drug resistance in colorectal cancer.
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Duwe, Gregor [Verfasser]. „Etablierung eines Tiermodells zur Untersuchung des Sinusoidalen Obstruktionssyndroms in der Leber von Mäusen, behandelt mit Oxaliplatin, einem VEGF-Inhibitor und anschließender Leberteilresektion / Gregor Duwe“. Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2020. http://d-nb.info/1223926176/34.
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Stieg, Mareike [Verfasser], und Max [Akademischer Betreuer] Schnurr. „Chemoimmuntherapie des Pankreaskarzinoms: Kombination aus bifunktioneller 5'-Triphosphat-modifizierter siRNA gegen TGFβ1 und den Chemotherapeutika Gemcitabin, Oxaliplatin und 5-Fluoruracil / Mareike Stieg. Betreuer: Max Schnurr“. München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2014. http://d-nb.info/1055907572/34.
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