HPV prevalence among healthy Italian male sexual partners of women with cervical HPV infection.

Genital human papillomavirus (HPV) is the causative agent of cervical cancer and is the most common sexually transmitted infection. Only limited and controversial data are available regarding HPV transmission in male sexual partners of women with cervical intraepithelial neoplasia (CIN). The aim of this study was to investigate the prevalence and the genotype distribution of HPV in penile scrapings of a series of Italian men, who had no visible penile lesions and were partners of women who were affected, or had been affected previously by cervical intraepithelial neoplasia or who were infected with HPV. The concordance of the viral group in the infected partners was determined. A total of 77 penile scrapings were screened for HPV infection by the polymerase chain reaction, while 59 cervicovaginal brushings of their female partners were tested. 35% of evaluable male samples and 64% of female sexual partners were found to be HPV positive. In the 55 simultaneously evaluable couples, a concordance of 45% was found, 11 couples (20%) with both partners being HPV negative and 14 couples (25%) with both partners HPV positive (P=0.001). Six out of the 14 couples (43%), where both partners were HPV positive, harbored the same HPV genotype group. These data, although preliminary, could support further the hypothesis that male HPV infection is more frequent in sexual partners of HPV positive or women with cervical intraepithelial neoplasia indicating that men could represent an important source of HPV transmission between sex partners.

Immunohistochemical expression of p16(INK4a) is predictive of HR-HPV infection in cervical low-grade lesions.

The p16(INK4a) is a cyclin-dependent kinase inhibitor that decelerates the cell cycle by inactivating the cyclin-dependent kinases involved in the phosphorylation of the retinoblastoma protein (RB). Expression of E6 and E7 oncogenes of high-risk (HR) human papillomavirus (HPV), affecting the RB-p16 pathway, leads to p16 upregulation. Although it is widely reported that p16 is overexpressed in a high percentage of preneoplastic lesions and in almost all carcinomas of the uterine cervix, protein upregulation and its correlation with HPV infection in low-grade lesions is still being debated. In this study, we investigated in parallel, p16 expression and HPV infection in 100 cervical biopsies (17 normal tissues, 54 CIN1, 10 CIN2, 11 CIN3, eight invasive squamous cancers). Results obtained demonstrated that none of the 17 normal cervical tissues, evaluated by immunohistochemistry, presented p16 positivity whereas, starting from CIN1 (31%) to CIN2 (90%), CIN3 (100%) and carcinomas (100%), a constant and significant increase of protein overexpression (P<0.0001) was observed. In addition, p16 overexpression consistently showed elevated sensitivity (84%) and specificity (98%) in detecting HR-HPV infection with a high positive predictive value (97%) and negative predictive value (86%). Of interest, 93% of the p16-positive CIN1 were also HR-HPV infected. Our findings confirmed that p16 overexpression is associated to high-grade precancerous lesions and cervical carcinomas, and further demonstrated that immunohistochemical evaluation of p16 may be a useful biomarker in identifying HR-HPV-infected low-grade lesions.