This study aimed to investigate the role of miRNAs in HPV-mediated cervical pre-cancer and cancer cases in Indian population. We analysed the HPV infection and its genotypes in uterine cervical pre-cancer (n = 80), cancer (n = 200) and normal cervical samples (n = 150) by consensus sequence PCR followed by type specific PCRs. Also, microRNA profiling was done in a subset of cervical pre-cancer (n = 20), cancer cases (n = 50) and normal samples (n = 30) by real-time quantitative PCR (qRT-PCR). The prevalence of HPV infection in pre-cancer was found to be 81 % (65/80) and 94 % (188/200) in cancer cases, with most predominant high-risk HPV type-16 (HR-HPV-16) in 83 % of cancer and 91 % of pre- cancer cases, respectively. Whereas in controls, the HPV infection was found to be very low (5 %). The miRNA profiling revealed that in cervical pre-cancer, 100 miRNAs were significantly (p < 0.001) differentially expressed with 70 miRNAs upregulated and 30 miRNAs downregulated. In cervical cancer cases, 383 miRNA were found to be differentially expressed (p < 0.001), of which 350 miRNAs were upregulated and 33 miRNAs were downregulated. We also observed that 182 miRNAs were differentially expressed (p < 0.001) in HPV-16/18-positive (SiHa/HeLa) cell lines compared with HPV-negative (C33A) cell line. In addition, we identified the novel microRNAs such as miR-892b, miR-500, miR-888, miR-505 and miR-711 in cervical precancerous lesions and cervical cancer cases in Indian population. Taken together, the study demonstrates a crucial role of microRNAs in cervical cancer, which may serve as potential early diagnostic markers for cervical carcinogenesis.
Keywords: Cervical cancer; HPV; MicroRNAs.