MicroRNA-15b is induced with E2F-controlled genes in HPV-related cancer.
Ontology highlight
ABSTRACT: Background
MicroRNAs (miRNAs) are important regulators of cellular processes and are found to be deregulated in many cancers. We here analysed the miRNA expression in anal carcinomas. In a previous study, we found that our anal carcinoma tumours were divided into two groups based on the expression of E2F-regulated genes. Therefore, we searched for miRNAs that could reproduce this grouping.Methods
A global screen of the miRNA population was performed using real-time quantitative PCR (RT-qPCR) array methods and differentially expressed miRNAs were identified. Real-time-qPCR was used to verify the expression levels of selected miRNAs and genes in a larger collection of biopsies. A siRNA-mediated knockdown of human papilloma virus (HPV)16 E7 in a cervical cell line was performed to assess the effect of E7 on miR-15b.Results
The grouping of tumours into two groups based on the expression of E2F-controlled genes was confirmed in a larger collection of anal carcinoma tumours. The expression of miR-15b was shown to be highly correlated with that of five selected E2F-induced genes (CCNA2, CCNB1, CCNB2, MSH6 and MCM7). A knockdown of HPV16 E7 resulted in decreased levels of miR-15b in Ca Ski cells.Conclusion
MiR-15b expression correlates with E2F-regulated genes in anal carcinoma and appears to be part of the E2F-regulatory network.
SUBMITTER: Myklebust MP
PROVIDER: S-EPMC3242611 | biostudies-literature |
REPOSITORIES: biostudies-literature
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