Association between JC virus and colorectal cancer: systematic review and meta-analysis

Objective: Given the probable role of JC virus in associate with increasing the odds of colorectal cancer, this study was conducted systematically to evaluate the association between JC virus and colorectal cancer. Materials and methods: Systematic reviews of the articles published prior to January 1, 2019 without time and place limitations were done independently through the PubMed, ISI, EMBASE and Medline main databases. The heterogeneity rate was assessed through I2, Chi2 and Tau2, and the sensitivity analysis and meta-regression were used to investigate the source of heterogeneity among the studies. Results: 24 studies with a sample size of 2576 were finally entered into the meta-analysis. The results showed that the prevalence of JC virus in colorectal cancer tissues was about 43% (95% CI: 29% -58%). The meta-analysis results also showed that the presence of JCV in colorectal tissues increased the odds of colorectal cancer 4.70 times as much (OR Pooled = 4.70; 95% CI: 2.95-7.50). Also, the results of the sub-group analysis indicated that the presence of JC virus, compared with the tissues adjacent to the tumour and the healthy control tissues, increased the odds of colorectal cancer (OR Pooled = 4.50, 95% CI: 2.09-9.65 and OR Pooled = 4.70, 95% CI: 2.95-7.50) respectively. Conclusion: The meta-analysis showed that as an oncogene virus, JC could increase the odds of colorectal cancer, reinforcing the hypothesis on the role of viral factors in the pathogenesis of cancers.