scholarly journals Oncogenic viruses and their role in tumor formation

2005 ◽  
Vol 133 (7-8) ◽  
pp. 384-387 ◽  
Author(s):  
Maja Cupic ◽  
Ivana Lazarevic ◽  
Nada Kuljic-Kapulica
Keyword(s):  
Cell Growth ◽  
Cell Transformation ◽  
Rna Viruses ◽  
Tumor Formation ◽  
Cellular Growth ◽  
Oncogenic Viruses ◽  
Dna Viruses ◽  
Host Chromosome ◽  
Promoter Sequences ◽  
Cellular Genes

Oncogenic viruses trigger persistent infections, which can stimulate uncontrolled cell growth by inducing cell transformation. Different oncogenic viruses use different mechanisms for infecting cells. Most oncogenic DNA viruses integrate transforming sets of genes into the host chromosome and encode proteins that bind and inactivate cell growth regulatory proteins, such as p53 and retinoblastoma gene product. Tumorous RNA viruses use different oncogenic mechanisms. Some of them encode oncogenic proteins that are almost identical to the cellular proteins involved in the control of cellular growth. The overproduction or altered function of these oncogenic materials stimulates cell growth. These RNA viruses can cause tumors rapidly. The second group of oncoviruses integrates their promoter sequences and viral enhancers near to the cellular growth-stimulating gene, initiating the transformation of the cell. The third group of RNA tumor viruses encodes a protein tax that transactivates the expression of cellular genes. Virus-induced malignant transformation of the cell represents the first step in the complex process of oncogenesis.

Oncogenesis and the Lucké Virus

1968 ◽  
Vol 26 ◽  
pp. 200-201
Author(s):  
A. E. Vatter ◽  
J. Zambernard
Keyword(s):  
Rna Viruses ◽  
Vegetative State ◽  
Temperature Sensitive ◽  
Structural Level ◽  
Oncogenic Viruses ◽  
Dna Viruses ◽  
Leopard Frogs ◽  
Renal Adenocarcinoma ◽  
Induced Tumors ◽  
Northern Leopard Frogs

Oncogenic viruses, like viruses in general, can be divided into two classes, those that contain deoxyribonucleic acid (DNA) and those that contain ribonucleic acid (RNA). The RNA viruses have been recovered readily from the tumors which they cause whereas, the DNA-virus induced tumors have not yielded the virus. Since DNA viruses cannot be recovered, the bulk of present day investigations have been concerned with RNA viruses.The Lucké renal adenocarcinoma is a spontaneous tumor which occurs in northern leopard frogs (Rana pipiens) and has received increased attention in recent years because of its probable viral etiology. This hypothesis was first advanced by Lucké after he observed intranuclear inclusions in some of the tumor cells. Tumors with inclusions were examined at the fine structural level by Fawcett who showed that they contained immature and mature virus˗like particles.The use of this system in the study of oncogenic tumors offers several unique features, the virus has been shown to contain DNA and it can be recovered from the tumor, also, it is temperature sensitive. This latter feature is of importance because the virus can be transformed from a latent to a vegetative state by lowering or elevating the environmental temperature.

Association of normal oral mucosa with DNA of the main types of oncogenic viruses

2020 ◽  
pp. 60-63
Author(s):  
S.I. Kutukova ◽  
A.B. Chukhlovin ◽  
A.I. Yaremenko ◽  
Yu.V. Ivaskova ◽  
A.Ya. Razumova ◽  
...  
Keyword(s):  
Oral Mucosa ◽  
Epstein Barr Virus ◽  
Oncogenic Viruses ◽  
Viral Dna ◽  
Dna Viruses ◽  
Normal Oral Mucosa ◽  
Barr Virus ◽  
Ebv Dna ◽  
Epstein Barr ◽  
Hpv 18

The aim of the study was to assess the prevalence of DNA viruses (HSV I and II, CMV, EBV, HPV6.11, HPV16 and HPV18) in the native oral mucosa of healthy volunteers (n=50; 30 men (60.0%), 20 women (40.0%); 25—74 years, median age — 55.0 years (95% CI 47.60-56.76)). All samples of the normal oral mucosa were detected by real-time PCR to detect viral DNA. The majority of the examined — 76% (33/50) — revealed the DNA: one type of viral DNA in 17 (38.00%) of the examined, a combination of the two types in 14 (28.00%). In the normal oral mucosa, DNA of Epstein-Barr virus was significantly more often detected: 15 (30.00%) (p = 0.0276) and human papilloma viruses 27 (54.00%) (p <0.0001), especially HPV-18 (24 (48.00%)): mono-association in 9 (18.00%) examined and in 7 (14.00%) in combination with EBV DNA (p = 0.0253).

scholarly journals HOXB4 inhibits the proliferation and tumorigenesis of cervical cancer cells by downregulating the activity of Wnt/β-catenin signaling pathway

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Dan Lei ◽  
Wen-Ting Yang ◽  
Peng-Sheng Zheng
Keyword(s):  
Cervical Cancer ◽  
Cell Growth ◽  
Signaling Pathway ◽  
Cancer Cell ◽  
Tumor Formation ◽  
Cervical Cancer Cell ◽  
Cancer Cell Growth ◽  
Bioinformatics Analyses

AbstractHomeobox B4 (HOXB4), which belongs to the homeobox (HOX) family, possesses transcription factor activity and has a crucial role in stem cell self-renewal and tumorigenesis. However, its biological function and exact mechanism in cervical cancer remain unknown. Here, we found that HOXB4 was markedly downregulated in cervical cancer. We demonstrated that HOXB4 obviously suppressed cervical cancer cell proliferation and tumorigenic potential in nude mice. Additionally, HOXB4-induced cell cycle arrest at the transition from the G0/G1 phase to the S phase. Conversely, loss of HOXB4 promoted cervical cancer cell growth both in vitro and in vivo. Bioinformatics analyses and mechanistic studies revealed that HOXB4 inhibited the activity of the Wnt/β-catenin signaling pathway by direct transcriptional repression of β-catenin. Furthermore, β-catenin re-expression rescued HOXB4-induced cervical cancer cell defects. Taken together, these findings suggested that HOXB4 directly transcriptional repressed β-catenin and subsequently inactivated the Wnt/β-catenin signaling pathway, leading to significant inhibition of cervical cancer cell growth and tumor formation.

scholarly journals Intercellular Transmission of Naked Viruses through Extracellular Vesicles: Focus on Polyomaviruses

Viruses ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 1086
Author(s):  
Francois Helle ◽  
Lynda Handala ◽  
Marine Bentz ◽  
Gilles Duverlie ◽  
Etienne Brochot
Keyword(s):  
Immune System ◽  
Extracellular Vesicles ◽  
Rna Viruses ◽  
Viral Transmission ◽  
Viral Fitness ◽  
Host Cells ◽  
Dna Viruses ◽  
Recent Advances ◽  
Viral Particles ◽  
Similar Strategy

Extracellular vesicles have recently emerged as a novel mode of viral transmission exploited by naked viruses to exit host cells through a nonlytic pathway. Extracellular vesicles can allow multiple viral particles to collectively traffic in and out of cells, thus enhancing the viral fitness and diversifying the transmission routes while evading the immune system. This has been shown for several RNA viruses that belong to the Picornaviridae, Hepeviridae, Reoviridae, and Caliciviridae families; however, recent studies also demonstrated that the BK and JC viruses, two DNA viruses that belong to the Polyomaviridae family, use a similar strategy. In this review, we provide an update on recent advances in understanding the mechanisms used by naked viruses to hijack extracellular vesicles, and we discuss the implications for the biology of polyomaviruses.

VirusTaxo: Taxonomic classification of virus genome using multi-class hierarchical classification by k-mer enrichment

2021 ◽  
Author(s):  
Rajan Saha Raju ◽  
Abdullah Al Nahid ◽  
Preonath Shuvo ◽  
Rashedul Islam
Keyword(s):  
Genome Sequence ◽  
Rna Viruses ◽  
Hierarchical Classification ◽  
Classification Problem ◽  
Virus Genome ◽  
Taxonomic Classification ◽  
Dna Viruses ◽  
Dna And Rna ◽  
Full Length Genome

AbstractTaxonomic classification of viruses is a multi-class hierarchical classification problem, as taxonomic ranks (e.g., order, family and genus) of viruses are hierarchically structured and have multiple classes in each rank. Classification of biological sequences which are hierarchically structured with multiple classes is challenging. Here we developed a machine learning architecture, VirusTaxo, using a multi-class hierarchical classification by k-mer enrichment. VirusTaxo classifies DNA and RNA viruses to their taxonomic ranks using genome sequence. To assign taxonomic ranks, VirusTaxo extracts k-mers from genome sequence and creates bag-of-k-mers for each class in a rank. VirusTaxo uses a top-down hierarchical classification approach and accurately assigns the order, family and genus of a virus from the genome sequence. The average accuracies of VirusTaxo for DNA viruses are 99% (order), 98% (family) and 95% (genus) and for RNA viruses 97% (order), 96% (family) and 82% (genus). VirusTaxo can be used to detect taxonomy of novel viruses using full length genome or contig sequences.AvailabilityOnline version of VirusTaxo is available at https://omics-lab.com/virustaxo/.

scholarly journals Fetal Bovine Serum-Derived Extracellular Vesicles Persist within Vesicle-Depleted Culture Media

2018 ◽  
Vol 19 (11) ◽  
pp. 3538 ◽  
Author(s):  
Brandon Lehrich ◽  
Yaxuan Liang ◽  
Pooya Khosravi ◽  
Howard Federoff ◽  
Massimo Fiandaca
Keyword(s):  
Cell Growth ◽  
Extracellular Vesicles ◽  
Bovine Serum ◽  
Culture Media ◽  
Fetal Bovine Serum ◽  
Cellular Growth ◽  
Primary Astrocyte ◽  
Fetal Bovine ◽  
Cell Growth And Viability

It is known that culture media (CM) promotes cellular growth, adhesion, and protects explanted primary brain cells from in vitro stresses. The fetal bovine serum (FBS) supplement used in most CM, however, contains significant quantities of extracellular vesicles (EVs) that confound quantitative and qualitative analyses from the EVs produced by the cultured cells. We quantitatively tested the ability of common FBS EV-depletion protocols to remove exogenous EVs from FBS-supplemented CM and evaluated the influence such methods have on primary astrocyte culture growth and viability. We assessed two methodologies utilized for FBS EV removal prior to adding to CM: (1) an 18-h ultracentrifugation (UC); and (2) a commercial EV-depleted FBS (Exo-FBS™). Our analysis demonstrated that Exo-FBS™ CM provided the largest depletion (75%) of total FBS EVs, while still providing 6.92 × 109 ± 1.39 × 108 EVs/mL. In addition, both UC and Exo-FBS™ CM resulted in poor primary astrocyte cell growth and viability in culture. The two common FBS EV-depletion methods investigated, therefore, not only contaminate in vitro primary cell-derived EV analyses, but also provide a suboptimal environment for primary astrocyte cell growth and viability. It appears likely that future CM optimization, using a serum-free alternative, might be required to advance analyses of cell-specific EVs isolated in vitro.

scholarly journals Patient-individual cancer cell lines and tissue analysis delivers no evidence for a role of DNA virus infection on colorectal cancer oncogenesis

2019 ◽  
Author(s):  
Michael Gock ◽  
Marcel Kordt ◽  
Stephanie Matschos ◽  
Christina S. Mullins ◽  
Michael Linnebacher
Keyword(s):  
Cell Lines ◽  
Molecular Subtypes ◽  
Morphological Changes ◽  
Tissue Analysis ◽  
Oncogenic Viruses ◽  
Dna Viruses ◽  
Viral Particles ◽  
Specific Sequences

Abstract Background Several DNA viruses are highly suspicious to have oncogenic effects in humans. This study investigates the presence of potentially oncogenic viruses such as SV40, JCV, BKV and EBV in patient-derived colorectal carcinoma (CRC) cells typifying all molecular subtypes of CRC. Methods Sample material (gDNA and cDNA) of a total of 49 patient-individual CRC cell lines and corresponding primary material from 11 patients, including normal, tumor-derived and metastasis-derived tissue were analyzed for sequences of SV40, JVC, BKV and EBV using endpoint PCR. In addition, the susceptibility of CRC cells to JCV and BKV was examined using a long-term cultivation approach of patient-individual cells in the presence of viruses. Results No virus-specific sequences could be detected in all specimens. Likewise, no morphological changes were observed and no evidence for viral infection or integration could be provided after long term CRC cell cultivation in presence of viral particles. Conclusions In summary, the presented data suggest that there is no direct correlation between tumorigenesis and viral load and consequently no evidence for a functional role of the DNA viruses included into this analysis in CRC development.

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