Expression of miRNAs dysregulated by Human papillomavirus 16 E5/E6/E7 oncoproteins in cervical carcinogenesis

Abstract

Cervical cancer is the third most common malignancy in women worldwide. Almost all cervical cancers are associated with human papilloma viruses (HPV), but the majority of women infected with HPV do not develop cervical cancer. We aimed to find putative microRNAs (miRNAs) that serve as diagnostic biomarkers for cervical cancer in high-risk HPV positive patients. We analyzed the miRNA expression profiles of 12 cervical tissues using the hybridization method (nCounter Human v3 miRNA Expression Assay). Significant miRNAs, based on arbitrary

fold change

≥ 2 (p ≤ 0.01), were verified by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) using StepOnePlusTM Real-time PCR System (Applied Biosystems, Foster City, CA, USA). We additionally performed the same qRT-PCR analysis on 29 cervical tissues. For verified miRNAs by qRT-PCR, we investigated the effects of HPV16 E5/E6/E7 on dysregulated miRNAs through cervical cancer cell experiments. Upon screening of 800 human miRNAs, eight genes (miR-9-5p, -136-5p, -148a-3p, -190a-5p, -199b-5p, -382-5p, -597-5p, -655-3p) showed significant differences in the HPV16-positive cervical cancer (PC) group compared to the HPV16-positive normal (PN) group. QRT-PCR analysis showed miR-148a-3p, -190a-5p, -199b-5p and -655-3p were significantly decreased in the PC group compared to the PN group (p < 0.05). In the silencing experiment of HPV16 E5 and HPV16 E6/E7, miR-148a-3p was inversely increased in both cervical cancer cell lines at silencing 72 hrs. The silencing of HPV16 E6/E7 in SiHa cells induced the increase of miR-199b-5p and miR-190a-5p. In conclusion, three miRNAs (miR-148a-3p, miR-199b-5p, miR-190a-5p) might be serve as early biomarkers in women with HPV16 infection for cancer development. Especially, all three oncoproteins of HPV16 were associated with down-regulation of miR-148a-3p and HPV16 E6/E7 reduced miR-199b-5p and miR-190a-5p expression in cervical carcinoma.