Downregulation of external death receptor genes FAS and DR5 in colorectal cancer samples positive for human papillomavirus infection

Mohamed S, Gouda W. Case-control study: Unveiling human polyomaviruses and papillomavirus in Egyptian colorectal cancer patients

BACKGROUND

Colorectal cancer (CRC) is a cancer type that is thought to be influenced by human papillomaviruses (HPVs) and human polyomaviruses (HPyVs). In Egypt, CRC ranks as the 7th most common cancer, accounting for 3.47% of male cancers and 3% of female cancers. However, there is currently a lack of information regarding the presence of PyVs and HPVs co-infection specifically in CRC cases in Egypt. Therefore, the aim of this study was to investigate the occurrence of HPVs and HPyVs (JCPyV, BKPyV, and SV40) infections, as well as co-infections, among CRC patients in Egypt. Additionally, the study aimed to assess any potential association between these viral infections and tumor stages.

METHODS

In the present study, we analyzed a total of 51 tissue samples obtained from Egyptian CRC patients, along with 19 polyps' samples. Our investigation focused on the detection and genotyping of HPyVs using Real-Time PCR. Additionally, we employed real-time PCR for the detection of HPVs, and for their genotyping, we utilized a combination of PCR amplification followed by sequencing.

RESULTS

In our study, we found evidence of HPyVs infection in the CRC patients, specifically SV40 (25.5%) and BKPyV (19.6%). However, JCPyV was not detected in the samples that were examined. Additionally, we discovered that HPV was present in 43.1% of the CRC patients. When considering viral co-infections, 19.6% of the CRC samples showed coexistence of multiple viruses, while no co-infections were found in the polyps samples. Importantly, we observed a significant correlation between the presence of HPVs and advanced colorectal tumor grades B2 and D.

CONCLUSION

Our findings provide valuable data for the detection of oncogenic viruses in colorectal cancer (CRC) and underscore the association of viral co-infections with advanced tumor stages. However, further research with larger cohorts is necessary to validate these findings and strengthen their significance in the field of CRC.

Colorectal cancer and gut viruses: a visualized analysis based on CiteSpace knowledge graph

Background

Gut microbiome is a complex community of microbes present in the human gut and plays an important role in the occurrence and progression of colorectal cancer (CRC). However, the relationship between virus and CRC has not been fully understood.

Objective

To explore the hot spots and research trends in the field of CRC and virus.

Methods

By using the bibliometric analysis tool CiteSpace and based on the articles of the Web of Science Core Collection (WoSCC) database, the country, institution, highly cited literature, keywords and so on were visually analyzed.

Results

A total of 356 research articles on CRC from 2001 to 2023 were thoroughly analyzed. The USA and China have made the largest contribution in the field of virus and CRC. The Helmholtz Association published the most papers. There were relatively few cooperations among institutions from different countries. The results of keyword cluster analysis proved that the literature on the relationship between human cytomegalovirus (CMV) and CRC was the most widely studied aspect in this field. "Gut microbiota," "inflammatory bowel disease," "hepatitis b virus," and "human papillomavirus infection" are the current research hotspots; "oncolytic virus," "apoptosis," and "gut microbiome" are the recent research frontiers and should be paid closer attention.

Conclusion

By using CiteSpace bibliometric software, the visual analysis reflected the research trends and hot topics of virus and CRC. In addition, the prevalence and mechanism of specific virus on CRC were also reviewed, which provides valuable references for future CRC research.

Coinfection of HPVs Is Associated with Advanced Stage in Colorectal Cancer Patients from Qatar

High-risk human papillomaviruses (HPVs) are considered risk factors in the origin of several human malignancies, such as breast, cervical, head and neck, as well as colorectal cancers. However, there are no data reported on the HPV status in colorectal cancer in the State of Qatar. Therefore, we herein examined the presence of high-risk HPVs (16, 18, 31, 33, 35, 45, 51, 52, and 59), using polymerase chain reaction (PCR) in a cohort of 100 Qatari colorectal cancer patients, and their association with tumor phenotype. We found that high-risk HPV types 16, 18, 31, 35, 45, 51, 52, and 59 were present in 4, 36, 14, 5, 14, 6, 41, and 17% of our samples, respectively. Overall, 69 (69%) of the 100 samples were HPV positive; among these, 34/100 (34%) were positive for single HPV subtypes, while 35/100 (35%) of the samples were positive for two or more HPV subtypes. No significant association was noted between the presence of HPV and tumor grade, stage, or location. However, the presence of coinfection of HPV subtypes strongly correlated with advanced stage (stage 3 and 4) colorectal cancer, indicating that the copresence of more than one HPV subtype can significantly worsen the prognosis of colorectal cancer. The results from this study imply that coinfection with high-risk HPV subtypes is associated with the development of colorectal cancer in the Qatari population.

Viruses in Cancers of the Digestive System: Active Contributors or Idle Bystanders?

The human virome, which is a collection of all the viruses that are present in the human body, is increasingly being recognized as an essential part of the human microbiota. The human gastrointestinal tract and related organs (e.g., liver, pancreas, and gallbladder)-composing the gastrointestinal (or digestive) system-contain a huge number of viral particles which contribute to maintaining tissue homeostasis and keeping our body healthy. However, perturbations of the virome steady-state may, both directly and indirectly, ignite/sustain oncogenic mechanisms contributing to the initiation of a dysplastic process and/or cancer progression. In this review, we summarize and discuss the available evidence on the association and role of viruses in the development of cancers of the digestive system.

Does human papillomavirus cause human colorectal cancer? Applying Bradford Hill criteria postulates

The role of human papillomavirus (HPV) in human colorectal cancer (CRC) has already been widely investigated worldwide with conflicting results. Although researchers have tried to establish the link between HPV and CRC through a statistical meta-analysis of the previous studies associating HPV with CRC, they failed to establish a more reliable link due to the shortcomings of the statistical meta-analysis. In the present study, we identified population-wide studies relating HPV with CRC through the PubMed search engine. Then, we examined the available data of HPV prevalence in CRC and normal/benign samples and applied the postulates of Bradford Hill criteria on the available evidence to investigate the association between HPV and CRC. The Bradford Hill criteria are very old, reliable and widely accepted for establishing a link between the cause and disease. In addition, to further enhance the reliability of the outcomes, we have also evaluated the methodologies of the previous studies to address the possibility of false-negative and false-positive results. After a careful evaluation of the extracted data against the postulates of Bradford Hill criteria, it was observed that none of the studies fulfil all the major postulates of Bradford Hill criteria for causation including temporality, consistency, biological gradient, experiment, coherence, specificity and analogy. Hence, no causal relationship has been suggested between HPV and CRC patients of the any included population. The results failed to prove the causal relationship between HPV and CRC and suggested HPV as a coparticipant in the pathogenesis of CRC.

Detection of Human papillomavirus and the role of p16INK4a in colorectal carcinomas

INTRODUCTION

Human papillomavirus (HPV) infection is associated with the development of anogenital and head and neck cancers. In recent years a potential role of HPV in colorectal cancer (CRC) has been suggested.

OBJECTIVE

To investigate the presence of HPV in colorectal carcinomas and to study the role of p16INK4a as a marker of transcriptionally active HPV infection. In addition, to investigate the correlation between these findings and the CRC prognostic factors.

METHODS

Case control study with 92 cases of colorectal cancers, 75 controls of normal tissue adjacent to the tumor, and 30 controls of precursor lesions, including polyps and colorectal adenomas. Paraffinized samples were used, HPV detection and genotyping were performed by PCR and reverse hybridization by using the INNO LIPA kit, with SPF10 plus primers. The expression of the p16INK4a protein was investigated using immunohistochemistry. Data analysis was performed using descriptive, univariate statistics and survival curves were calculated by using the Kaplan Meier and log-rank method.

RESULTS

HPV was detected in 13% of the cases and the most prevalent genotype was HPV 16. HPV DNA was not detected in either control groups. The high expression of p16INK4a was observed in 30% of the cases, but it was not associated to the presence of HPV. The overall survival was 53.3% and was influenced by prognostic factors such as later stage, lymph node and distant metastasis.

CONCLUSIONS

Based on these results, HPV is unlikely to be involved in colorectal carcinogenesis and p16INK4a expression is not a relevant marker of transcriptionally active HPV infection in CRC.

Polymorphisms rs763110 in FASL is linked to hepatitis C virus infection among high-risk populations

BACKGROUND

The Fas cell surface death receptor (FAS) and Fas ligand (FASL) can participate in the apoptosis of immune cells and target cells infected with a virus through the FAS-FASL signalling pathway. The decoy receptor 3 (DCR3) can competitively inhibit the binding of FAS to FASL. Our aim is to investigate the effect of single nucleotide polymorphisms (SNPs) in FAS, FASL and DCR3 on hepatitis C virus (HCV) infection.

METHODS

Four SNPs (rs763110 in FASL, rs1324551 and rs2234767 in FAS and rs2257440 in DCR3) were genotyped in 1495 controls free of HCV, 522 individuals with spontaneous HCV clearance and 732 patients with hepatitis C virus infection. The RegulomeDB database and RNAfold web servers were used to explore potential biological functions of SNPs.

RESULTS

FASL rs763110 was associated with susceptibility to HCV infection, and not to CHC. The odds ratio (95% confidence interval) of HCV infection in high-risk populations carrying FASL rs763110-TT was 1.82 (1.36-2.51, P < 0.001) compared to that of CC genotypes and 1.93 (1.43-2.60, P < 0.001) higher than that of CC + CT genotypes. Based on computer simulation, FASL rs763110-T may affect the transcription of mRNA by affecting the binding of a transcription factor, leading to structural changes in mRNA.

CONCLUSION

The genetic variant in FASL is linked with HCV infection, but not to spontaneous HCV clearance.

Human Papillomaviruses and Epstein-Barr Virus Interactions in Colorectal Cancer: A Brief Review

Human papillomaviruses (HPVs) and the Epstein-Barr virus (EBV) are the most common oncoviruses, contributing to approximately 10%-15% of all malignancies. Oncoproteins of high-risk HPVs (E5 and E6/E7), as well as EBV (LMP1, LMP2A and EBNA1), play a principal role in the onset and progression of several human carcinomas, including head and neck, cervical and colorectal. Oncoproteins of high-risk HPVs and EBV can cooperate to initiate and/or enhance epithelial-mesenchymal transition (EMT) events, which represents one of the hallmarks of cancer progression and metastasis. Although the role of these oncoviruses in several cancers is well established, their role in the pathogenesis of colorectal cancer is still nascent. This review presents an overview of the most recent advances related to the presence and role of high-risk HPVs and EBV in colorectal cancer, with an emphasis on their cooperation in colorectal carcinogenesis.

Reversine induces cell cycle arrest and apoptosis via upregulation of the Fas and DR5 signaling pathways in human colorectal cancer cells

Reversine, a 2,6‑diamino‑substituted purine analogue, has been reported to be effective in tumor suppression via induction of cell growth arrest and apoptosis of cancer cells. However, it remains unclear whether reversine exerts anticancer effects on human colorectal cancer cells. In the present study, in vitro experiments were conducted to investigate the anticancer properties of reversine in human colorectal cancer cells. The effect of reversine on human colorectal cancer cell lines, SW480 and HCT‑116, was examined using a WST‑1 cell viability assay, fluorescence microscopy, flow cytometry, DNA fragmentation, small interfering RNA (siRNA) and western blotting. Reversine treatment demonstrated cytotoxic activity in human colorectal cancer cells. It also induced apoptosis by activating poly(ADP‑ribose) polymerase, caspase‑3, ‑7 and ‑8, and increasing the levels of the pro‑apoptotic protein second mitochondria‑derived activator of caspase/direct inhibitor of apoptosis‑binding protein with low pI. The pan‑caspase inhibitor Z‑VAD‑FMK attenuated these reversine‑induced apoptotic effects on human colorectal cancer cells. Additionally, reversine treatment induced cell cycle arrest in the subG1 and G2/M phases via increase in levels of p21, p27 and p57, and decrease in cyclin D1 levels. The expression of Fas and death receptor 5 (DR5) signaling proteins in SW480 and HCT116 cells was upregulated by reversine treatment. Reversine‑induced apoptosis and cell cycle arrest were suppressed by inhibition of Fas and DR5 expression via siRNA. In conclusion, Reversine treatment suppressed tumor progression by the inhibition of cell proliferation, induction of cell cycle arrest and induction of apoptosis via upregulation of the Fas and DR5 signaling pathways in human colorectal cancer cells. The present study indicated that reversine may be used as a novel anticancer agent in human colorectal cancer.

Prevalência de câncer colorretal associado ao papilomavírus humano: uma revisão sistemática com metanálise

RESUMO: Introdução: O câncer colorretal é um dos tipos de tumor mais prevalentes na população mundial. A mortalidade causada por esses tumores malignos continua elevada e mantém-se praticamente no mesmo nível nas últimas décadas. Entre os fatores de risco já estabelecidos para o desenvolvimento do câncer estão as infecções por patógenos ou vírus. Entre os vírus, o papilomavírus humano (HPV) é o mais prevalente, tendo mais de 180 cepas, das quais 40 estão diretamente relacionadas com infecções anogenitais. Objetivo: Avaliar de forma sistemática, com metanálise, os principais estudos que associam o HPV ao câncer colorretal. Métodos: Como estratégia de busca foi adotada a lógica baseada em descritores específicos (idioma inglês), vinculados aos operadores booleanos (AND/OR). As buscas foram aplicadas nas bases de dados PubMed, ScienceDirect e Scientific Electronic Library Online (SciELO), no período de abril e maio de 2015. Resultados: Foram avaliadas 1.549 amostras, sendo 956 (61,7%) do sexo masculino. Foram diagnosticados 630/1.358 casos de câncer colorretal por HPV (51,9%). Destes, 408/767 (51,9%) eram do sexo masculino e 404/598 (67,5%) foram associados aos HPVs 16 e 18, com prevalência tumoral na região do colo (253/411; 61,3%). Do total de 598 amostras para estimativa das prevalências de HPV-16 e HPV-18, a quantidade de casos com valores muito semelhantes foi de 204 (31,7%) e 200 (35,8%), respectivamente. Foram verificados valores relativamente expressivos na região do colo, 253 (61,3%), e na região retal, 158 (38,7%). Conclusão: Após a realização do presente estudo, a associação entre HPV e câncer colorretal ficou evidente, não havendo distinção entre gêneros, com valores muito semelhantes entre o HPV-16 e o HPV-18.

Mathematical model of tumor-immune surveillance

We present a novel mathematical model involving various immune cell populations and tumor cell populations. The model describes how tumor cells evolve and survive the brief encounter with the immune system mediated by natural killer (NK) cells and the activated CD8(+) cytotoxic T lymphocytes (CTLs). The model is composed of ordinary differential equations describing the interactions between these important immune lymphocytes and various tumor cell populations. Based on up-to-date knowledge of immune evasion and rational considerations, the model is designed to illustrate how tumors evade both arms of host immunity (i.e. innate and adaptive immunity). The model predicts that (a) an influx of an external source of NK cells might play a crucial role in enhancing NK-cell immune surveillance; (b) the host immune system alone is not fully effective against progression of tumor cells; (c) the development of immunoresistance by tumor cells is inevitable in tumor immune surveillance. Our model also supports the importance of infiltrating NK cells in tumor immune surveillance, which can be enhanced by NK cell-based immunotherapeutic approaches.