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HPV-16 long control region (LCR) has been shown to be the most variable region of the HPV-16 genome and may play important roles in viral persistence and the development of cervical cancer. This study aimed to assess the risk of HPV-16 LCR variants for cervical cancer in women of Southwest China. 2146 cervical scrapings of volunteer outpatients and 74 cervical cancer tissues were screened.14 entire HPV-16 LCRs from asymptomatic carriers and 34 entire HPV-16 LCRs from cervical cancer patients were successfully amplified and sequenced to align to others described. 58 different point mutations were detected in 54 nucleotide sites of HPV-16 LCR. G7193T and G7521A variants, accounting for 100% of the infections, were predicted to locate at the binding site for FOXA1 and SOX9, respectively. A7730C variant which showed a high mutation frequency in cervical cancer was predicted to be a binding site for the cellular transcription factor PHOX2A. In addition, phylogenetic analysis displayed a high prevalence of A lineage in HPV-16 LCR in this Southwest China population. This study may help understanding of the intrinsic geographical relatedness and the correlations between LCR mutations and the development of carcinogenic lesions in Southwest China population. And it provides useful data for the further study of the biological function of HPV-16 LCR variants. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are small, non-coding RNAs that are critical regulators of various diseases. MicroRNA-20a (miR-20a) has previously significantly altered in a range of cancers. In this study, we detected the relationship between miR-20a and the development of cervical cancer by qRT-PCR, we found that the expression level of miR-20a was significantly higher in cervical cancer patients than in normal controls, the aberrant expression of miR-20a was correlated with lymph node metastasis, histological grade and tumor diameter. Then we successfully established the stable anti-miR-20a cervical cancer cell lines by lentivirus. Inhibited miR-20a prevented tumor progression by modulating cell cycle, apoptosis, and metastasis in vitro and in vivo. TIMP2 and ATG7 were proved to be direct targets of miR-20a, using luciferase assay and western blot. These results indicate that miR-20a suppresses the proliferation, migration and invasion of cervical cancer cell through targeting ATG7 and TIMP2. Our results support the involvement of miR-20a in cervical tumorigenesis, especially lymph node metastasis. We propose that miRNAs might be used as therapeutic agent for cervical cancer. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the effects of miR-1246 on proliferation, invasion, and migration in the human (CSCC) cell line SiHa. Methods: SiHa cells were assigned into three groups: miR-1246 analog; miR-1246 antagonist; and control. The MTT, transwell, and wound healing assays were performed to evaluate the proliferation, invasion, and migration abilities of SiHa cells, respectively. Western blot was carried out to detect protein expression of thrombospondin-2 (THBS2) before and after transfection with miR-1246 analog, antagonist, or control. In addition, a THBS2 3′-UTR-containing dual luciferase plasmid was generated and co-transfected with miR-1246, the inhibitor, or non-specific miRNA, into SiHa cells to observe its effects on THBS2-driven luciferase enzyme activity. Results: MTT, transwell, and wound healing assays revealed that proliferation, migration, and invasion were all significantly enhanced ( P < 0.01) in SiHa cells transfected with miR-1246 analog, but were suppressed in those transfected with the miR-1246 antagonist. Western blot data showed that miR-1246 analog-transfected SiHa cells had significantly decreased THBS2 expression when compared with control-transfected cells (gray value = 6.28 ± 10.22 vs. 9.58 ± 17.58; P = 0.013) while those transfected with the miR-1246 antagonist had significantly increased THBS2 expression (gray value = 12.90 ± 19.81; P = 0.037). Moreover, SiHa cells co-transfected with miR-1246 and the THBS2 3′-UTR-containing plasmid exhibited decreased luciferase enzyme activity compared with the control. Conclusion: MiR-1246 induced CSCC SiHa cell proliferation, invasion and migration. Preliminary evidence suggests that miR-1246 might promote CSCC tumorigenesis and progression by the suppression of its target gene THBS2. [ABSTRACT FROM AUTHOR]

Backgroud: Variations in HPV LCR/E6/E7 have been shown to be associated with the viral persistence and cervical cancer development. So far, there are few reports about the polymorphisms of the HPV-58 LCR/E6/E7 sequences in Southwest China. This study aims to characterize the gene polymorphisms of the HPV-58 LCR/E6/E7 sequences in women of Southwest China, and assess the effects of variations on the immune recognition of viral E6 and E7 antigens. Methods: Twelve LCR/E6/E7 of the HPV-58 isolates were amplified and sequenced. A neighbor-joining phylogenetic tree was constructed by MEGA 7.0, followed by the secondary structure prediction of the related proteins using PSIPRED v3.3. The selection pressure acting on the HPV-58 E6 and E7 coding regions was estimated by Bayes empirical Bayes analysis of PAML 4.8. Meanwhile, the MHC class-I and II binding peptides were predicted by the ProPred-I server and ProPred server. The transcription factor binding sites in the HPV-58 LCR were analyzed using the JASPAR database. Results: Twenty nine SNPs (20 in the LCR, 3 in the E6, 6 in the E7) were identified at 27 nucleotide sites across the HPV-58 LCR/E6/E7. From the most variable to the least variable, the nucleotide variations were LCR > E7 > E6. The combinations of all the SNPs resulted in 11 unique sequences, which were clustered into the A lineage (7 belong to A1, 2 belong to A2, and 2 belong to A3). An insertion (TGTCAGTTTCCT) was found between the nucleotide sites 7280 and 7281 in 2 variants, and a deletion (TTTAT) was found between 7429 and 7433 in 1 variant. The most common non-synonymous substitution V77A in the E7 was observed in the sequences encoding the α-helix. 63G in the E7 was determined to be the only one positively selected site in the HPV-58 E6/E7 sequences. Six non-synonymous amino acid substitutions (including S71F and K93 N in the E6, and T20I, G41R, G63S/D, and V77A in the E7) were affecting multiple putative epitopes for both CD4+ and CD8+ T-cells. In the LCR, C7265G and C7266T were the most variable sites and were the potential binding sites for the transcription factor SOX10. Conclusion: These results provide an insight into the intrinsic geographical relatedness and biological differences of the HPV-58 variants, and contribute to further research on the HPV-58 epidemiology, carcinogenesis, and therapeutic vaccine development. [ABSTRACT FROM AUTHOR]

Highlights: [•] We investigated the prevalence and E6/E7 variants of HPV-58 in Southwest China. [•] 4 single nucleotide changes were observed in HPV-58 E6 sequences. [•] 8 single nucleotide changes were observed in HPV-58 E7 sequences. [•] HPV-58 E6/E7 variants identified belonged to the Southeast Asia lineage. [•] There was no evidence of positive selection in sequence alignment of HPV-58 E6/E7. [ABSTRACT FROM AUTHOR]