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Relevant bibliographies by topics / DNA topoisomerasa II beta

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Academic literature on the topic 'DNA topoisomerasa II beta'

Author: Grafiati

Published: 28 June 2021

Last updated: 17 February 2022

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Journal articles on the topic "DNA topoisomerasa II beta"

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Sharma, Kaushal K., Brijendra Singh, Somdutt Mujwar, and Prakash S. Bisen. "Molecular Docking Based Analysis to Elucidate the DNA Topoisomerase IIβ as the Potential Target for the Ganoderic Acid; A Natural Therapeutic Agent in Cancer Therapy." Current Computer-Aided Drug Design 16, no. 2 (March 25, 2020): 176–89. http://dx.doi.org/10.2174/1573409915666190820144759.

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Introduction: Intermediate covalent complex of DNA-Topoisomerase II enzyme is the most promising target of the anticancer drugs to induce apoptosis in cancer cells. Currently, anticancer drug and chemotherapy are facing major challenges i.e., drug resistance, chemical instability and, dose-limiting side effect. Therefore, in this study, natural therapeutic agents (series of Ganoderic acids) were used for the molecular docking simulation against Human DNATopoisomerase II beta complex (PDB ID:3QX3). Methods: Molecular docking studies were performed on a 50 series of ganoderic acids reported in the NCBI-PubChem database and FDA approved anti-cancer drugs, to find out binding energy, an interacting residue at the active site of Human DNA-Topoisomerase II beta and compare with the molecular arrangements of the interacting residue of etoposide with the Human DNA topoisomerase II beta. The autodock 4.2 was used for the molecular docking and pharmacokinetic and toxicity studies were performed for the analysis of physicochemical properties and to check the toxicity effects. Discovery studio software was used for the visualization and analysis of docked pose. Results and Conclusion: Ganoderic acids (GS-1, A and DM) were found to be a more suitable competitor inhibitor among the ganoderic acid series with appropriate binding energy, pharmacokinetic profile and no toxicity effects. The interacting residue (Met782, DC-8, DC-11 and DA-12) shared a chemical resemblance with the interacting residue of etoposide present at the active site of human topoisomerase II beta receptor.

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Bernard, F. X., S. Sablé, B. Cameron, J. Provost, J. F. Desnottes, J. Crouzet, and F. Blanche. "Glycosylated flavones as selective inhibitors of topoisomerase IV." Antimicrobial Agents and Chemotherapy 41, no. 5 (May 1997): 992–98. http://dx.doi.org/10.1128/aac.41.5.992.

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Three flavonoids which promoted Escherichia coli topoisomerase IV-dependent DNA cleavage were isolated from cottonseed flour and identified as quercetin 3-O-beta-D-glucose-[1,6]-O-alpha-L-rhamnose (rutin), quercetin 3-O-beta-D-galactose-[1,6]-O-alpha-L-rhamnose, and quercetin 3-O-beta-D-glucose (isoquercitrin). The most active one (rutin) also inhibited topoisomerase IV-dependent decatenation activity (50% inhibitory concentration, 64 microg/ml) and induced the SOS response of a permeable E. coli strain. Derivatives of quercetin glycosylated at position C-3 were shown to induce two site-specific DNA cleavages of pBR322 DNA, which were mapped by DNA sequence analysis to the gene encoding resistance to tetracycline. Cleavage at these sites was hardly detectable in cleavage reactions with quercetin or fluoroquinolones. None of the three flavonoids isolated from cottonseeds had any stimulatory activity on E. coli DNA gyrase-dependent or calf thymus topoisomerase II-dependent DNA cleavage, and they were therefore specific to topoisomerase IV. These results show that selective inhibitors of topoisomerase IV can be derived from the flavone structure. This is the first report on a DNA topoisomerase inhibitor specific for topoisomerase IV.

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Strehl, Sabine, Karin Nebral, Helmut H. Schmidt, and Oskar A. Haas. "Topoisomerase (DNA) II Beta 180 kDa TOP2B) - A New NUP98 Fusion Partner." Blood 106, no. 11 (November 16, 2005): 2849. http://dx.doi.org/10.1182/blood.v106.11.2849.2849.

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Abstract The nucleoporin 98 kDa (NUP98) gene has been reported to be fused to 18 different partner genes in various hematological malignancies with 11p15 aberrations. The most frequently observed fusion partners of NUP98 belong to the homeobox family of transcription factors, whereas the non-HOX NUP98 fusion partners comprise a heterogeneous group of genes that are associated with a wide range of biological functions. Cytogenetic analysis of an adult de novo acute myeloid leukemia (AML-M5a) revealed a t(3;11)(p24;p15) indicating fusion of NUP98 with a novel partner gene. Fluorescence in situ hybridization (FISH) analysis with the NUP98-specific clone 1173K1 showed a split signal, suggesting that NUP98 was indeed disrupted. Selection of possible NUP98 partner genes was performed by computer-aided analysis of the 3p24 region using the University of California Santa Cruz genome browser. Out of the genes located at 3p24, TOP2B was selected as a fusion partner candidate gene. Dual-color fusion gene-specific FISH and RT-PCR analyses verified that NUP98 was indeed fused to TOP2B. In addition to the reciprocal NUP98-TOP2B and TOP2B-NUP98 in-frame fusion transcripts, an alternatively spliced out-of-frame TOP2B-NUP98 transcript that resulted in a premature stop codon was detected. Analysis of the genomic breakpoints revealed typical signs of non-homologous end joining resulting from error-prone DNA repair. TOP2B encodes a type II topoisomerase, which is involved in DNA transcription, replication, recombination, and mitosis. Type II DNA topoisomerases exist as homodimers, with each subunit consisting of three functional domains: an N-terminal ATPase domain, a central DNA breakage-rejoining domain, which contains a nucleotide-binding motif and the catalytic tyrosine, and a relatively poorly conserved C-terminal domain. The C-termini of the two TOP2 isoforms seem to be important for subcellular localization and functional bipartite nuclear localization signal (NLS) sequences as well as nuclear export signals (NES) are located in these domains. The NUP98-TOP2B fusion transcript fuses the N-terminal FG repeat and GLEBs motifs of NUP98 with the C-terminal domain of TOP2B, thereby retaining the functional NLS but eliminating the NES. Consequently, the putative reciprocal TOP2B-NUP98 chimeric protein retains the ATPase, the DNA breakage-rejoining, and the NES domains of TOP2B that are fused to the ribonucleoprotein-binding and the NLS domains of NUP98. The shorter out-of-frame TOP2Bexon24-NUP98exon14 fusion transcript might encode a truncated TOP2B isoform that consists of the ATPase, the DNA breakage-rejoining, and NES domains, which are fused to 18 fusion partner-unrelated amino acids. All proteins encoded by non-HOX NUP98 fusion partners described to date contain regions with a significant probability to adopt a coiled-coil conformation, and protein analysis with the COILS 2.2 and the MULTICOIL programs revealed this remarkable feature also in the C-terminal region of TOP2B. Intriguingly, this is only the second description of a chromosomal rearrangement that involves a topoisomerase and both TOP1 and TOP2B are fused to NUP98. This suggests that the choice of partner genes for NUP98 is not random, and that NUP98-TOP fusions may represent a distinct group, similar to the NUP98-HOX fusions.

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Biersack, H., S. Jensen, I. Gromova, I. S. Nielsen, O. Westergaard, and A. H. Andersen. "Active heterodimers are formed from human DNA topoisomerase II alpha and II beta isoforms." Proceedings of the National Academy of Sciences 93, no. 16 (August 6, 1996): 8288–93. http://dx.doi.org/10.1073/pnas.93.16.8288.

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Jenkins, J. R., M. J. Pocklington, and E. Orr. "The F1 ATP synthetase beta-subunit: a major yeast novobiocin binding protein." Journal of Cell Science 96, no. 4 (August 1, 1990): 675–82. http://dx.doi.org/10.1242/jcs.96.4.675.

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Novobiocin affects DNA metabolism in both prokaryotes and eukaryotes, resulting in cell death. In prokaryotes, the drug is a specific inhibitor of DNA gyrase, a type II topoisomerase that can be purified on a novobiocin-Sepharose column. The yeast type II topoisomerase is neither the biochemical, nor the genetic target of the antibiotic. We have purified the major yeast novobiocin binding proteins and identified one of them as the beta-subunit of the yeast mitochondrial F1 ATP synthetase, a protein highly conserved throughout evolution. The inactivation of this protein might explain the toxic effects of novobiocin on higher eukaryotic cells.

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LONN, Ulf, and Sigrid LONN. "5,6-Dichloro-1-beta-O-ribofuranosylbenzimidazole induces DNA damage by interfering with DNA topoisomerase II." European Journal of Biochemistry 164, no. 3 (May 1987): 541–45. http://dx.doi.org/10.1111/j.1432-1033.1987.tb11160.x.

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Khazeem, Mushtaq M., Ian G. Cowell, Lauren F. Harkin, John W. Casement, and Caroline A. Austin. "Transcription of carbonyl reductase 1 is regulated by DNA topoisomerase II beta." FEBS Letters 594, no. 20 (August 30, 2020): 3395–405. http://dx.doi.org/10.1002/1873-3468.13904.

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Vassetzky, Y. S., Q. Dang, P. Benedetti, and S. M. Gasser. "Topoisomerase II forms multimers in vitro: effects of metals, beta-glycerophosphate, and phosphorylation of its C-terminal domain." Molecular and Cellular Biology 14, no. 10 (October 1994): 6962–74. http://dx.doi.org/10.1128/mcb.14.10.6962.

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We present a novel assay for the study of protein-protein interactions involving DNA topoisomerase II. Under various conditions of incubation we observe that topoisomerase II forms complexes at least tetrameric in size, which can be sedimented by centrifugation through glycerol. The multimers are enzymatically active and can be visualized by electron microscopy. Dephosphorylation of topoisomerase II inhibits its multimerization, which can be restored at least partially by rephosphorylation of multiple sites within its 200 C-terminal amino acids by casein kinase II. Truncation of topoisomerase II just upstream of the major phosphoacceptor sites reduces its aggregation, rendering the truncated enzyme insensitive to either kinase treatments or phosphatase treatments. This is consistent with a model in which interactions involving the phosphorylated C-terminal domain of topoisomerase II aid either in chromosome segregation or in chromosome condensation.

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Vassetzky, Y. S., Q. Dang, P. Benedetti, and S. M. Gasser. "Topoisomerase II forms multimers in vitro: effects of metals, beta-glycerophosphate, and phosphorylation of its C-terminal domain." Molecular and Cellular Biology 14, no. 10 (October 1994): 6962–74. http://dx.doi.org/10.1128/mcb.14.10.6962-6974.1994.

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We present a novel assay for the study of protein-protein interactions involving DNA topoisomerase II. Under various conditions of incubation we observe that topoisomerase II forms complexes at least tetrameric in size, which can be sedimented by centrifugation through glycerol. The multimers are enzymatically active and can be visualized by electron microscopy. Dephosphorylation of topoisomerase II inhibits its multimerization, which can be restored at least partially by rephosphorylation of multiple sites within its 200 C-terminal amino acids by casein kinase II. Truncation of topoisomerase II just upstream of the major phosphoacceptor sites reduces its aggregation, rendering the truncated enzyme insensitive to either kinase treatments or phosphatase treatments. This is consistent with a model in which interactions involving the phosphorylated C-terminal domain of topoisomerase II aid either in chromosome segregation or in chromosome condensation.

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Muller, M. T., and V. B. Mehta. "DNase I hypersensitivity is independent of endogenous topoisomerase II activity during chicken erythrocyte differentiation." Molecular and Cellular Biology 8, no. 9 (September 1988): 3661–69. http://dx.doi.org/10.1128/mcb.8.9.3661.

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Endogenous topoisomerase II cleavage sites were mapped in the chicken beta A-globin gene of 12- to 14-day embryonic erythrocytes. A major topoisomerase II catalytic site was mapped to the 5' end of the globin gene which contained a nucleosome-free and DNase I-hypersensitive site and additional but minor sites were mapped to the second intron and 3' of the gene to a tissue-specific enhancer. Cleavage sites, mapped in situ by indirect end labeling, were aligned to single-base-pair resolution by comparison to a consensus sequence derived for vertebrate topoisomerase II catalytic sites. In contrast to embryonic erythrocytes, endogenous topoisomerase II cleavages were not detected in erythrocytes from peripheral blood of adult chickens; therefore, as the transcriptional activity of the beta A-globin gene declines during terminal differentiation of erythrocytes, the activity of topoisomerase II in situ declines as well, despite the fact that DNase I hypersensitivity persists. The results showed that DNase I-hypersensitive chromatin can be maintained in the absence of topoisomerase II activity and suggested that topoisomerase II acts at hypersensitive sites because of an inherent attraction to some preexisting combination of DNA sequence or chromatin structure associated with DNase I-hypersensitive regions.

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Dissertations / Theses on the topic "DNA topoisomerasa II beta"

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Errington, Fiona. "An investigation into the cytotoxic mechanisms of DNA topoisomerase II poisons and catalytic inhibitors : the role of DNA topoisomerase II alpha and beta." Thesis, University of Newcastle Upon Tyne, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340718.

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Padget, Kay. "Quantitative analysis and drug sensitivity of human DNA topoisomerase II alpha and beta." Thesis, University of Newcastle Upon Tyne, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246093.

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McNamara, Suzan. "Topoisomerase II beta negatively modulates retinoic acid receptor alpha function : a novel mechanism of retinoic acid resistance in acute promyelocytic leukemia." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=115693.

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Interactions between the retinoic acid receptor alpha (RARalpha) and coregulators play a key role in coordinating gene transcription and myeloid differentiation. In acute promyelocytic leukemia (APL), RARalpha is fused with the promyelocytic leukemia (PML) gene, resulting in the expression of the fusion protein PML/RARalpha. Here, I report that topoisomerase II beta (topoIIbeta) associates with and negatively modulates PML/RARalpha and RARalpha transcriptional activity, and increased levels and association of topoIIbeta cause resistance to retinoic acid (RA) in APL cell lines. Knock down of topoIIbeta was able to overcome resistance by permitting RA-induced differentiation and increased RA-gene expression. Overexpression of topoIIbeta, in clones from an RA-sensitive cell line, conferred resistance by a reduction in RA-induced expression of target genes and differentiation. Chromatin immunoprecipitation assays indicate that topoIIbeta is bound to an RA-response element, and inhibition of topoIIbeta causes hyper-acetylation of histone 3 at lysine 9 and activation of transcription. These results identify a novel mechanism of resistance in APL and provide further insights to the role of topoIIbeta in gene regulation and differentiation.
Studies to determine the mechanism by which topoIIbeta protein is regulated found that levels of protein kinase C delta (PKCdelta) correlated with topoIIbeta protein expression. Moreover, activation of PKCdelta, by RA or PMA, led to an increase of topoIIbeta protein levels. Most notably, in NB4-MR2 cells, we observed increased phosphorylation levels of threonine 505 on PKCdelta, a marker of activation. Inhibition of PKCdelta was able to overcome the topoIIbeta repressive effects on RA-target genes. In addition, the combination of RA and PKCdelta inhibition led to increased expression of the granulocytic marker, CD11c, in NB4 and NB4-MR2 cells. These results suggest that PKCdelta regulates topoIIbeta expression, and a constitutively active PKCdelta in the NB4-MR2 cell line leads to overexpression of topoIIbeta.
In conclusion, these studies demonstrate that topoIIbeta associates with RARalpha, binds to RAREs and plays a critical role in RA dependent transcriptional regulation and granulocytic differentiation. In addition, I show that topoIIbeta overexpression leads to RA resistance and provide evidence that topoIIbeta protein levels are regulated via a mechanism involving the PKCdelta pathway. This work has contributed to an enhanced understanding of the role of topoIIbeta in gene regulation and brings novel perspectives in the treatment of RA-resistance in APL.

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Xue, Yu Lord Susan T. "Study protein-protein interaction in methyl-directed DNA mismatch repair in E. coli exonuclease I Exo I and DNA helicas II UvrD; A minimal exonuclease domain of WRN forms a hexamer on DNA and possesses both 3'-5' exonuclease and 5'-protruding strand endonuclease activities; Solving the structure of the ligand-binding domain of the pregnane-xenobiotic-receptor with 17[beta] estradiol and T1317 /." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2008. http://dc.lib.unc.edu/u?/etd,2015.

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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2008.
Title from electronic title page (viewed Feb. 17, 2009). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Chemistry." Discipline: Chemistry; Department/School: Chemistry.

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Burns, Kristi Lee. "An exploration of biochemistry including biotechnology, structural characterization, drug design, and chromatographic analyses." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/29593.

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Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2007.
Committee Chair: Sheldon W. May ; Committee Members: Donald F. Doyle, Leslie T. Gelbaum, Stanley H. Pollock, and James Powers. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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Jaščevská, Nikola. "Vliv topoisomerasy II beta na citlivost nádorových buněk k protinádorové terapii." Master's thesis, 2021. http://www.nusl.cz/ntk/nusl-446116.

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Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Nikola Jaščevská Supervisor: PharmDr. Anna Jirkovská, Ph.D. Title of diploma thesis: The effects of topoisomerase II beta on the sensitivity of the cancer cells to the antineoplastics Topoisomerase II (TOP II) is a cellular enzyme responsible for solving topological problems of double-stranded DNA. Alpha and beta isoforms of TOP II are different gene products having similar catalytic activities. The expression of TOP IIα is cell-cycle dependent, peaking in G2/M phase, while TOP II isoform is expressed constitutively throughout the cell cycle. It is therefore present also in non-proliferating differentiated cells. Anthracycline antibiotics are an old class of anticancer drugs, belonging to TOP II poisons. Although their clinical usefulness is high, the incidence of side effects (especially myelotoxicity and cardiotoxicity) may limit the therapy. The key role of TOP II inhibition, which is present also in cardiomyocytes, has been increasingly discussed. Dexrazoxane, the only clinically used cardioprotective, leads to depletion of TOP II in cardiomyocytes, which may explain its cardioprotection. Although TOP II was previously shown to be dispensable for cellular proliferation, its possible...

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Schmidt, Uta [Verfasser]. "Das multifunktionelle Signalprotein Topoisomerase-IIβ-Bindeprotein-1 [Topoisomerase-II-Beta-Bindeprotein-1] (TopBP1) und seine Funktion in der DNA-Schadenserkennung und Replikation / von Uta Schmidt." 2008. http://d-nb.info/990000516/34.

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Karešová, Aneta. "Detekce kovalentních komplexů DNA s proteiny jako metoda stanovení poškození DNA topoizomerázovými jedy." Master's thesis, 2016. http://www.nusl.cz/ntk/nusl-345331.

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Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Aneta Karešová Supervisor: PharmDr. Anna Jirkovská, PhD. Title of diploma thesis: DNA-protein covalent complexes detection as the means for the assessment of the DNA damage induced by topoisomerase poisons. Topoisomerase II is essential cellular enzyme, which modifies the secondary structure of DNA. By introducing a temporary double strand break to DNA it relieves a structural tension raised during transcription and translation. Absolutely indispensable is the role of topoisomerase II in the separation of sister chromatids synthesized in the S-phase of the cell cycle. The mechanism of DNA cleavage involves a covalent bond formed between active site tyrosine and 5' phosphate on both of the DNA strands and through the formed break the other strand or the other DNA molecule can pass. After that, the DNA strands are rejoined and topoisomerase II is detached. The indispensability of topoisomerase II mainly for proliferating cells makes it a great target for the antineoplastic drugs and the molecules belonging to the class of topoisomerase II inhibitors (etoposide, anthracyclines) are amongst the most useful anticancer drugs in the clinical practice. These clinically used "topoisomerase...

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Klieber, Robin. "Použití RNA interference pro ovlivnění hladin DNA topoisomerasy II v nádorových buňkách a její vliv na protinádorový účinek antracyklinových cytostatik." Master's thesis, 2019. http://www.nusl.cz/ntk/nusl-396819.

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Charles University Faculty of Pharmacy in Hradec Králové Department od Biochemical Sciences Candidate: Bc. Robin Klieber Supervisor: PharmDr. Anna Jirkovská, Ph.D. Title of thesis: The use of RNA interference for the modification of DNA topoisomerase II levels in cancer cells and its influence on the antineoplastic effect of anthracyclines. Topoisomerase II (TOP II) is an enzyme that alters the topological state of the DNA double helix during physiological processes through the formation of transient DNA double strand breaks. Two TOP II isoforms are known: TOP IIα is essential for proper separation of chromosomes in mitotic cells, whereas TOP IIβ is primarily associated with gene transcription. Anthracycline antibiotics (ANT) belong to the group of topoisomerase poisons that stabilize the covalent complex of TOP II and DNA. This prevents the religation of the DNA double strand breaks and thus causes irreversible DNA damage leading to programmed cell death. Although ANTs are frequently administered in various antineoplastic protocols (hematooncological malignancies, hormone-dependent tumors and others), the therapy still possess a high risk of irreversible cardiotoxicity. The mechanism of cardiotoxicity remains unraveled. However, it has been previously discussed that TOP IIβ inhibition could play a...

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萩原, 和美. "Prox 1 overexpression of Hela cells inhibits PKC beta II transcription through promoter DNA methylation." Thesis, 2012. http://hdl.handle.net/2237/16914.

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Book chapters on the topic "DNA topoisomerasa II beta"

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Mohammed Ali Jassim, Marwa, Majid Mohammed Mahmood, and Murtada Hafedh Hussein. "Human Herpetic Viruses and Immune Profiles." In Innate Immunity in Health and Disease. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.96340.

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Herpesviruses are large, spherical, enveloped viral particles with linear double-stranded DNA genome. Herpesvirus virion consists of an icosahedral capsid containing viral DNA, surrounded by a protein layer called tegument, and enclosed by an envelope consisting of a lipid bilayer with various glycoproteins. Herpesviruses persist lifelong in their hosts after primary infection by establishing a latent infection interrupted recurrently by reactivations. The Herpesviridae family is divided into three subfamilies; α-herpesviruses, β-herpesviruses, and γ-herpesviruses based on the genome organization, sequence homology, and biological properties. There are eight human herpes viruses: Herpes simplex virus type 1 and 2 (HSV-1, −2) andVaricella-zoster virus (VZV), which belong to the α-herpesvirus subfamily; Human cytomegalovirus (HCMV), and Human herpesvirus type 6 and 7 (HHV-6,HHV-7), which belong to the β-herpesvirus subfamily; and Epstein–Barr virus (EBV) and Kaposi’s sarcoma-associated herpesvirus (KSHV) or Human herpesvirus 8 (HHV-8), which belong to the γ-herpesvirus subfamily. Within this chapter, we summarize the current knowledge about EBV and CMV, regarding their genome organization, structural characteristics, mehanisms of latency, types of infections, mechanisms of immune escape and prevention. Epstein–Barr Virus (EBV) genome encodes over 100 proteins, of which only (30) proteins are well characterized, including the proteins expressed during latent infection and lytic cycle proteins. Based on major variation in the EBNA-2 gene sequence, two types of EBV are recognized, EBV type 1 and 2. Epstein–Barr virus types occur worldwide and differ in their geographic distribution depending on the type of virus. EBV spreads most commonly through bodily fluids, especially saliva. However, EBV can also spread through blood, blood transfusions, and organ transplantations. The EBV is associated with many malignant diseases such as lymphomas, carcinomas, and also more benign such as infectious mononucleosis, chronic active infection. The EBV has also been suggested as a trigger/cofactor for some autoimmune diseases. Overall, 1–1.5% of the cancer burden worldwide is estimated to be attributable to EBV The latently infected human cancer cells express the most powerful monogenic proteins, LMP-1 and LMP-2(Latent Membrane Protein-1,-2), as well as Epstein–Barr Nuclear Antigens (EBNA) and two small RNAs called Epstein–Barr Encoded Small RNAs (EBERs). The EBV can evade the immune system by its gene products that interfering with both innate and adaptive immunity, these include EBV-encoded proteins as well as small noncoding RNAs with immune-evasive properties. Currently no vaccine is available, although there are few candidates under evaluation. Human cytomegalovirus (HCMV) is a ubiquitous beta herpesvirus type 5 with seroprevalence ranges between 60 to 100% in developing countries. CMV is spread from one person to another, usually by direct and prolonged contact with bodily fluids, mainly saliva, but it can be transmitted by genital secretions, blood transfusion and organ transplantation. In addition, CMV can be transmitted vertically from mother to child. CMV infection can result in severe disease for babies, people who receive solid organ transplants or bone marrow/stem cell transplants and people with severe immune suppression such as advanced human immunodeficiency virus (HIV) infection. The HCMV has several mechanisms of immune system evasion. It interferes with the initiation of adaptive immune responses, as well as prevent CD8+ and CD4+ T cell recognition interfering with the normal cellular MHC Class I and MHC Class II processing and presentation pathways. Challenges in developing a vaccine include adeptness of CMV in evading the immune system. Though several vaccine candidates are under investigation.

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