Background: High-risk human papillomavirus (HR-HPV) persistent infection is the main cause of cervical cancer and its precancerous lesions. A previous study showed that HPV16 and HPV58 infections were the most common infection types in the local region. Some studies also declared that HPV58 E7 variants increased the risk of cervical cancer among Asian populations. Objective: This study aimed to determine whether the HPV58 E7 T20I (C632T) variant promotes the malignant behavior of cervical cancer cells and the underlying mechanism of the HR-HPV E7 oncoprotein involved in the development of cervical cancer. Methods: CCK-8 and clone formation assays were used to detect cell proliferation ability. Transwell assays and cell wound healing assays were used to evaluate cell migration ability. Targeted knockdown of E2F1 expression using specific siRNA, RT-qPCR and Western blot were performed to assess gene expression changes. A chromatin immunoprecipitation assay was used to verify that E2F1 interacted with the TOP2A promoter region. Results: HPV58 E7 and HPV58 E7M oncoproteins increased the proliferation and migration ability of cervical cancer cells. However, the HPV58 E7 T20I variant did not promote malignant behaviors compared with wild-type HPV58 E7. HPV E7 and E7M oncoproteins increased the expression of TOP2A, BIRC5 and E2F1, and knockdown of HPV E7 decreased their expression. Low E2F1 expression reduced the expression of TOP2A and BIRC5 and inhibited the proliferation and migration ability of cervical cancer cells. E2F1 interacted with the TOP2A gene promoter region to promote its transcriptional expression. Conclusion: The HPV58 E7 T20I variant did not promote malignant behaviors compared with wild-type HPV58 E7. The HR-HPV E7 oncoprotein enhanced the proliferation and migration of cervical cancer cells, which was considered to be due to the HPV E7 oncoprotein, increasing the expression of BIRC5 and TOP2A by upregulating the transcription factor E2F1.
This meta-analysis systematically reviews the association between Toll-like receptor 9 polymorphisms and the risk of cervical cancer. Case-control studies focused on the association were collected from the PubMed, Web of Science, Cochrane Library, Embase, MEDLINE, CNKI, VIP, and Wanfang databases from inception to July 2017. We screened the studies and assessed the methodological quality of the included studies and extracted data. A meta-analysis was performed using RevMan 5.3 and Stata 12.0 software. Pooled odds ratios and 95% confidence intervals were employed to evaluate the strength of the associations between Toll-like receptor 9 polymorphisms and cervical cancer risk. A total of 9 studies comprising 3331 cervical cancer patients and 4109 healthy controls met the inclusion criteria. Of these, 8 studies contained information about G2848A (rs352140) and 4 studies contained information about -1486T/C (rs187084). Our results revealed that the associations between rs187084 and cervical cancer risk in the dominant model (p = 0.002) and heterozygous model (p = 0.002) were significant, with 1.30- and 1.32-fold increases in susceptibility, respectively, compared to that in the wild-type model. However, rs352140 was not related to cervical cancer regardless of whether the subgroup analysis was conducted (p > 0.05). In conclusion, there is a significant correlation between rs187084 and cervical cancer risk with the minor C allele increasing the risk of occurrence of cervical cancer. However, rs352140 is not associated with the occurrence of cervical cancer.
To evaluate the effectiveness of Human papillomavirus16/18 infection referral to colposcopy in cervical cancer screening for women aged 25 years and older in Chinese northwest region Shaan'xi province. A total of 2224 women were diagnosed with primary high‐risk HPV infection by HPV‐DNA genotyping technology during August 2014 to August 2015. A total of 1916 cases referred for colposcopy with histological evidence were enrolled, including 1124 women with HPV16/18 genotype and 792 with other High‐risk human papillomavirus genotypes. A total of 1916 women aged 25 years and older with HR‐HPV positive were referred to colposcopy. The distribution of HPV16, HPV18, and other HR‐HPVs infection were 49.22%, 9.45%, and 41.33%, respectively. 71.56% had normal cervical histology, 7.05% had Cervical Intraepithelial Neoplasia1, 8.82% had CIN2, 7.25% had CIN3, and 5.32% had cervical cancer. The percentage of positivity of HPV16 and HPV18 was highly associated with the relative risk of cervical lesion. The sensitivity and specificity of HPV16/18 for detection of CIN2+ (CIN3+) was 82.68% (92.12%) and 47.87% (46.15%), respectively. The positive predictive value and negative predictive value of HPV16/18 for detection of CIN2+ (CIN3+) was 30.16% (19.75%) and 91.03% (97.60%), respectively. HPV16 and HVP18 are the most common genotypes in high grade cervical lesions in Shaan'xi province. Meanwhile, these two types play predominant roles in the progression of high grade cervical lesion. Primary HPV16/18 detection has high sensitivity and negative predictive value in cervical cancer screening and the strategy for women with HPV16 and HPV18 infection referral to colposcopy is efficient and feasible in northwestern region of China.