Differential hypermethylation of genes in vulvar cancer and lichen sclerosus coexisting or not with vulvar cancer.

Squamous cell carcinoma (SCC) of the vulva is a heterogeneous disease, associated or not with vulvar lichen sclerosus (LS). The precursor role of LS in vulvar cancer is unclear. We studied the epigenetic alterations of RASSF1A, RASSF2A, p16, TSP-1 and MGMT genes in vulvar SCCs, LS associated with SCC, isolated LS and normal vulvar skin. Gene hypermethylation and human papillomavirus presence were evaluated by methylation-specific PCR and PCR/reverse line blot, respectively. High-risk human papillomavirus types were present in 16.7% of the patients with vulvar SCC. There were increasing percentages of hypermethylation of genes from isolated LS to LS associated with vulvar SCC and vulvar SCC. The genes were hypermethylated more frequently in vulvar SCC associated with LS than in those not associated with LS, MGMT and RASSF2A being unmethylated in LS not associated with vulvar SCC. TSP-1 hypermethylation was related to recurrence in patients with vulvar cancer. Conclusions are as follows: (i) the epigenetic inactivation of genes is a common event in vulvar SCC and is also present in adjacent lesions, implying a possible precursor role for these alterations; (ii) MGMT and RASSF2A hypermethylation are present exclusively in vulvar SCC and LS associated with SCC, and absent from isolated LS; and (iii) TSP-1 hypermethylation is a bad prognosis factor in vulvar SCC.

Human papillomavirus genotype attribution in invasive cervical cancer: a retrospective cross-sectional worldwide study.

BACKGROUND: Knowledge about the distribution of human papillomavirus (HPV) genotypes in invasive cervical cancer is crucial to guide the introduction of prophylactic vaccines. We aimed to provide novel and comprehensive data about the worldwide genotype distribution in patients with invasive cervical cancer. METHODS: Paraffin-embedded samples of histologically confirmed cases of invasive cervical cancer were collected from 38 countries in Europe, North America, central South America, Africa, Asia, and Oceania. Inclusion criteria were a pathological confirmation of a primary invasive cervical cancer of epithelial origin in the tissue sample selected for analysis of HPV DNA, and information about the year of diagnosis. HPV detection was done by use of PCR with SPF-10 broad-spectrum primers followed by DNA enzyme immunoassay and genotyping with a reverse hybridisation line probe assay. Sequence analysis was done to characterise HPV-positive samples with unknown HPV types. Data analyses included algorithms of multiple infections to estimate type-specific relative contributions. FINDINGS: 22,661 paraffin-embedded samples were obtained from 14,249 women. 10,575 cases of invasive cervical cancer were included in the study, and 8977 (85%) of these were positive for HPV DNA. The most common HPV types were 16, 18, 31, 33, 35, 45, 52, and 58 with a combined worldwide relative contribution of 8196 of 8977 (91%, 95% CI 90-92). HPV types 16 and 18 were detected in 6357 of 8977 of cases (71%, 70-72) of invasive cervical cancer. HPV types 16, 18, and 45 were detected in 443 of 470 cases (94%, 92-96) of cervical adenocarcinomas. Unknown HPV types that were identified with sequence analysis were 26, 30, 61, 67, 69, 82, and 91 in 103 (1%) of 8977 cases of invasive cervical cancer. Women with invasive cervical cancers related to HPV types 16, 18, or 45 presented at a younger mean age than did those with other HPV types (50·0 years [49·6-50·4], 48·2 years [47·3-49·2], 46·8 years [46·6-48·1], and 55·5 years [54·9-56·1], respectively). INTERPRETATION: To our knowledge, this study is the largest assessment of HPV genotypes to date. HPV types 16, 18, 31, 33, 35, 45, 52, and 58 should be given priority when the cross-protective effects of current vaccines are assessed, and for formulation of recommendations for the use of second-generation polyvalent HPV vaccines. Our results also suggest that type-specific high-risk HPV-DNA-based screening tests and protocols should focus on HPV types 16, 18, and 45.

Hypermethylation of the thrombospondin-1 gene is associated with poor prognosis in penile squamous cell carcinoma.

OBJECTIVE: To evaluate the presence of human papillomavirus (HPV) infection, the methylation status in the promoter region of thrombospondin-1 (TSP-1), RAS association domain family 1A (RASSF1-A) and p16 genes, and the expression of TSP-1, CD31, p16 and p53 proteins in patients diagnosed with penile cancer, and the possible associations between these variables and clinical and pathological features. PATIENTS AND METHODS: HPV types, gene promoter hypermethylation and protein expression were analysed by reverse line blot, methylation-specific polymerase chain reaction, and immunohistochemistry, respectively, in 24 penile squamous cell carcinomas. RESULTS: HPV infection was detected in 11 of 24 cases (46%), and TSP-1, RASSF1-A and p16 genes were hypermethylated in 46%, 42% and 38% of the tumours, respectively. TSP-1 hypermethylation was associated with unfavourable histological grade (grade 3; P = 0.033), vascular invasion (P = 0.023), weak expression of TSP-1 protein (P = 0.041), and shorter overall survival (P = 0.04). TSP-1 expression was not associated with microvessel density. However, RASSF1-A hypermethylation was more frequent in T1 tumours (P = 0.01), and p16 hypermethylation was not associated with any of the tested variables except for absence of p16 expression (P = 0.022). CONCLUSION: In summary, the epigenetic inactivation of TSP-1 and RASSF1-A genes is associated with pathological variables and seems to be of prognostic significance in penile cancer.