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Persistent infections caused by high-risk human papillomavirus (HR-HPV) are important, for the development of cervical lesions, but environmental and genetic factors are also related in the process of carcinogenesis. Among the genetic factors, the genetic variants of HR-HPV appear to be related to the risk of persistent infections. Therefore, the present study investigates variants of HPV31 E5 oncogene in cervical scraping samples from Brazilian women to assess their functional and structural effects, in order to identify possible repercussions of these variants on the infectious and carcinogenic process. Our results detected nucleotide changes previously described in the HPV31 E5 oncogene, which may play a critical role in the development of cancer due to its ability to promote cell proliferation and signal transmission. In our study, the interaction percentage of the 31E5 sequence generated by the Immune Epitope Server database and the Analysis Resource (IEDB) allowed us to include possible immunogenic epitopes with the MHC-I and MHC-II molecules, which may represent a possible relationship between protein suppression of the immune system. In the structural analysis of the HPV31 E5 oncoprotein, the N5D, I48 V, P56A, F80I and V64I polymorphisms can be found inserted within transmembrane regions. The P56A mutation has been predicted to be highly stabilizing and, therefore, can cause a change in protein function. Regarding the interaction of the E5 protein from HPV31 with the signaling of NF-kB pathway, we observed that in all variants of the E5 gene from HPV-31, the activity of the NF-kB pathway was increased compared to the prototype. Our study contributes to a more refined design of studies with the E5 gene from HPV31 and provides important data for a better understanding of how variants can be distinguished under their clinical consequences.

Human papillomavirus (HPV) is responsible for high-grade cervical lesions and cervical cancer. The inflammation plays a key role in cervical cancer progression. In this context, studies propose an association between TNFα and IL10 SNPs and susceptibility to HPV infection. The present work aimed to investigate the possible association between IL10 and TNFα promoter polymorphisms and HPV infection in the cervical carcinogenesis risk in women from Brazil. A total of 654 samples was evaluated in this study. HPV detection was performed by PCR and HPV genotyping was performed by PCR and sequencing of positive MY09/11 PCR product. Genotyping of IL10 SNPs (rs1800871 and rs1800896) was performed by High Resolution Melt analysis. Genotyping of TNFα SNP (rs1800629) was performed by fluorogenic allele-specific probes. The distribution of TNF-308 (rs1800629) allelic (p = 0.03) and genotype (p = 0.03) frequencies and HPV-58 infection has showed a statistically significant difference between case and control groups for the assessed TNFα polymorphism. When it comes to TNFα (rs1800629) allelic and genotypic distribution and HPVs 18 and 31 infections, no statistically significant differences between case and control groups were observed for the studied TNFα polymorphism. The allelic and genotypic distribution of IL10-819 (rs1800871) and IL10-1082 (rs1800896) and HPV infection (HPVs 58, 18 and 31) has showed no statistically significant differences between case and control groups for the assessed IL10 polymorphisms. Furthermore, it was observed that haplotypes were associated with an increased cervical cancer risk in HPVs 16, 18 and 58-positive women. It was observed that women carrying the GTA and ATG haplotypes had 3.85 and 17.99-fold, respectively, increased cervical cancer susceptibility when infected by HPV-58. In women infected with HPV-16 and HPV-18, statistically significant results in women carrying the GTA and ATA haplotypes was observed. They had a 2.32 and 3.67-fold, respectively, increased cervical cancer susceptibility when infected by these two HPV types. The analysis of the haplotypes distribution in women infected with HPV-31 has showed no statistically significant results. Our study indicates that the association of genetic polymorphism in inflammation-related genes represents a risk to the susceptibility in the development of cervical cancer in women infected by HPVs 16, 18 and 58.

Persistent infections by high-risk human papillomavirus (HR-HPV) are a necessary condition, but not sufficient for cervical cancer development. Genetic variants of HR-HPV appear to be related to the risk of persistent infections. The study performed a functional evaluation of variants of the HPV-31 promoter region (LCR). For this, cloning and subcloning of variants HPV-31/UFPE-21 HPV-31/UFPE-89, HPV-31/UFPE-66, E2 gene and prototype HPV-31 were performed. Transfection with different concentrations of E2 was done and the concentration of 25 ng was determined to be ideal for LCR activation. HPV-31/UFPE-21 and HPV-31/UFPE-89 have a greater ability to alter Nluc reporter gene expression levels and HPV-31/UFPE-66 showed decreased levels of gene expression of Nluc reporter gene compared to control. Statistical analysis showed a significant difference between the polymorphic LCR regions and the control (p 0.0001). A more refined profile of variants of HPV-31 and its importance for the prognosis of cervical lesions begins to be drawn.