Nanog, in Cooperation with AP1, Increases the Expression of E6/E7 Oncogenes from HPV Types 16/18.

Persistent infections with some types of human papillomavirus (HPV) constitute the major etiological factor for cervical cancer development. Nanog, a stem cell transcription factor has been shown to increase during cancer progression. We wanted to determine whether Nanog could modulate transcription of E6 and E7 oncogenes. We used luciferase reporters under the regulation of the long control region (LCR) of HPV types 16 and 18 (HPV16/18) and performed RT-qPCR. We found that Nanog increases activity of both viral regulatory regions and elevates endogenous E6/E7 mRNA levels in cervical cancer-derived cells. We demonstrated by in vitro mutagenesis that changes at Nanog-binding sites found in the HPV18 LCR significantly inhibit transcriptional activation. Chromatin immunoprecipitation (ChIP) assays showed that Nanog binds in vivo to the HPV18 LCR, and its overexpression increases its binding as well as that of c-Jun. Surprisingly, we observed that mutation of AP1-binding sites also affect Nanog's ability to activate transcription, suggesting cooperation between the two factors. We searched for putative Nanog-binding sites in the LCR of several HPVs and surprisingly found them only in those types associated with cancer development. Our study shows, for the first time, a role for Nanog in the regulation of E6/E7 transcription of HPV16/18.

Methylation in the promoter regions of WT1, NKX6-1 and DBC1 genes in cervical cancer tissues of Uygur women in Xinjiang

Abstract This study aimed to explore: 1) DNA methylation in the promoter regions of Wilms tumor gene 1 (WT1), NK6 transcription factor related locus 1 gene (NKX6-1) and Deleted in bladder cancer 1 (DBC1) gene in cervical cancer tissues of Uygur women in Xinjiang, and 2) the correlation of gene methylation with the infection of HPV16/18 viruses. We detected HPV16/18 infection in 43 normal cervical tissues, 30 cervical intraepithelial neoplasia lesions (CIN) and 48 cervical cancer tissues with polymerase chain reaction (PCR) method. Methylation in the promoter regions of the WT1, NKX6-1 and DBC1 genes in the above-mentioned tissues was measured by methylation-specific PCR (MSP) and cloning sequencing. The expression level of these three genes was measured by real-time PCR (qPCR) in 10 methylation-positive cervical cancer tissues and 10 methylation-negative normal cervical tissues. We found that the infection of HPV16 in normal cervical tissues, CIN and cervical cancer tissues was 14.0, 36.7 and 66.7%, respectively. The infection of HPV18 was 0, 6.7 and 10.4%, respectively. The methylation rates of WT1, NKX6-1 and DBC1 genes were 7.0, 11.6 and 23.3% in normal cervical tissues, 36.7, 46.7 and 30.0% in CIN tissues, and 89.6, 77.1 and 85.4% in cervical cancer tissues. Furthermore, WT1, NKX6-1 and DBC1 genes were hypermethylated in the high-grade squamous intraepithelial lesion (CIN2, CIN3) and in the cervical cancer tissues with infection of HPV16/18 (both P< 0.05). The expression of WT1, NKX6-1 and DBC1 was significantly lower in the methylation-positive cervical cancer tissues than in methylation-negative normal cervical tissues. Our findings indicated that methylation in the promoter regions of WT1, NKX6-1 and DBC1 is correlated with cervical cancer tumorigenesis in Uygur women. The infection of HPV16/18 might be correlated with methylation in these genes. Gene inactivation caused by methylation might be related to the incidence and development of cervical cancer.

Population-based prevalence of cervical infection with human papillomavirus genotypes 16 and 18 and other high risk types in Tlaxcala, Mexico.

BACKGROUND: Cervical cancer remains an important cause of cancer mortality for Mexican women. HPV 16/18 typing may help to improve cervical cancer screening. Here we present the prevalence of high-risk human papillomavirus (hrHPV) including HPV16 and HPV18 from the FRIDA (Forwarding Research for Improved Detection and Access) population. METHODS: Beginning in 2013, we recruited 30,829 women aged 30-64 in Tlaxcala, Mexico. Cervical samples were collected and tested for 14 hrHPV genotypes (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, and 68). We used logistic regression to estimate odds ratios with 95 % confidence intervals for hrHPV infections according to putative risk factors. RESULTS: Prevalence of infection with any of the 14 hrHPV types was 11.0 %. The age-specific prevalence of all hrHPV formed a U-shaped curve with a higher prevalence for women aged 30-39 and 50-64 than women aged 40-49. Across all age groups, 2.0 % of women were positive for HPV16 and/or HPV18 (HPV16/18), respectively. HPV16/18 prevalence also showed a U-shaped curve with increased prevalence estimates for women aged both 30-39 and 60-64. Both prevalence curves had a significant quadratic age coefficient. Infections with hrHPV were positively associated with an increased number of lifetime sexual partners, a history of sexually transmitted disease, being unmarried, use of hormonal contraception, having a history of smoking and reported condom use in the multivariate model. CONCLUSIONS: The FRIDA population has a bimodal distribution of both hrHPV and HPV16/18 positivity with higher prevalences at ages 30-39 and 60-64. These findings will help to evaluate triage algorithms based on HPV genotyping. TRIAL REGISTRATION: The trial is registered with ClinicalTrials.gov, number NCT02510027 .

Human papillomavirus infection in oral squamous cell carcinomas from Chilean patients.

Human papillomavirus (HPV) is the causal agent of cervical, anogenital and a subset of oropharyngeal carcinomas. In addition, the role of HPV in oral carcinogenesis has been suggested, although the findings are inconclusive. In this study, using conventional polymerase chain reaction (PCR) and genotyping by specific PCR and DNA sequencing, we analyzed the HPV presence in 80 oral squamous cell carcinomas (OSCCs) from Chilean subjects. In addition, we determined the expression of p16, p53, pRb and Ki-67 using immunohistochemistry (IHC). The CDKN2A (p16) promoter methylation was evaluated using methylation-specific PCR (MSP). HPV sequences were found in 9/80 (11%) OSCCs. Non-statistically significant association with p53, pRb, Ki-67 and p16 levels were found (p=0.77; 0.29; 0.83; 0.21, respectively). HPV-16 and 18 were the most prevalent HPV genotypes in 8/9 (89%) OSCCs. In addition, CDKN2A (p16) was methylated in 39% of OSCCs. No association with HPV presence (p=0.917) was found. These results suggest that HPV positive OSCCs are entities that do not resemble the molecular alterations of HPV-associated tumors in a Chilean population. More studies are warranted to determine the role of HPV in OSCCs.

Sustained efficacy, immunogenicity, and safety of the HPV-16/18 AS04-adjuvanted vaccine: final analysis of a long-term follow-up study up to 9.4 years post-vaccination.

HPV-023 (NCT00518336; ClinicalTrial.gov) is a long-term follow-up of an initial double-blind, randomized (1:1), placebo-controlled study (HPV-001, NCT00689741) evaluating the efficacy against human papillomavirus (HPV)-16/18 infection and associated cyto-histopathological abnormalities, persistence of immunogenicity, and safety of the HPV-16/18 AS04-adjuvanted vaccine. Among the women, aged 15-25 years, enrolled in HPV-001 and who participated in the follow-up study HPV-007 (NCT00120848), a subset of 437 women from five Brazilian centers participated in this 36-month long-term follow-up (HPV-023) for a total of 113 months (9.4 years). During HPV-023, anti-HPV-16/18 antibodies were measured annually by enzyme-linked immunosorbent assay (ELISA) and pseudovirion-based neutralisation assay (PBNA). Cervical samples were tested for HPV DNA every 6 months, and cyto-pathological examinations were performed annually. During HPV-023, no new HPV-16/18-associated infections and cyto-histopathological abnormalities occurred in the vaccine group. Vaccine efficacy (VE) against HPV-16/18 incident infection was 100% (95%CI: 66.1, 100). Over the 113 months (9.4 years), VE was 95.6% (86.2, 99.1; 3/50 cases in vaccine and placebo groups, respectively) against incident infection, 100% (84·1, 100; 0/21) against 6-month persistent infection (PI); 100% (61·4, 100; 0/10) against 12-month PI; 97·1% (82.5, 99.9; 1/30) against ≥ ASC-US; 95·0% (68.0, 99.9; 1/18) against ≥ LSIL; 100% (45.2, 100; 0/8) against CIN1+; and 100% (-128.1, 100; 0/3) against CIN2+ associated with HPV-16/18. All vaccinees remained seropositive to HPV-16/18, with antibody titers remaining several folds above natural infection levels, as measured by ELISA and PBNA. There were no safety concerns. To date, these data represent the longest follow-up reported for a licensed HPV vaccine.

Overcoming barriers to HPV vaccination: non-inferiority of antibody response to human papillomavirus 16/18 vaccine in adolescents vaccinated with a two-dose vs. a three-dose schedule at 21 months.

For middle and low-income countries, the cost of HPV vaccines remains challenging. We conducted an open-label nonrandomized clinical trial evaluating immune response to the HPV-16/18 AS04-adjuvanted vaccine administered on a standard (months (M) 0-1-6) versus extended schedule (M 0-6-60) at 7, 21, 60, 72 and 120 months post-vaccination. Participants were females recruited in Morelos, Mexico: 474 girls aged 9-10 years and 500 women aged 18-24 years receiving a standard schedule, and 1026 girls aged 9-10 years receiving an extended schedule (currently the girls in the extended schedule had received only the first 2 doses). This report presents the interim analysis results for non-inferiority between the regimes conducted with the current available data at 21 months after the first dose, with serum antibodies assessed by ELISA. A pre-stated margin of non-inferiority was defined by post-vaccination geometric mean titer (GMT) ratio (upper 95% confidence interval [CI]≤2.0) between the standard and the two-dose schedule in girls at month 21. Immune response to the vaccine was strongest in adolescent girls and in the 3-dose group. Statistical non-inferiority of the two-dose versus three-dose groups was demonstrated. At 21 months, comparing the adolescent 2-dose versus 3-dose groups, the GMT ratio and 95% CI were 1.66 (1.55-1.81) and 1.67 (1.51-1.86) for HPV16 and 18, respectively. The two-dose regimen was non-inferior when compared to the three-dose response in same-age girls and with women aged 18-24 years after 21 months of follow-up. The reduction in the number of doses from the current three-dose schedule may lower overall costs associated with the vaccination and increase accessibility and compliance with the recommended dosing of the HPV vaccine.