High prevalence of human papillomavirus and European variants of HPV 16 infecting concomitantly to cervix and oral cavity in HIV positive women.

OBJECTIVE: Identify the prevalence of HPV infections in the uterine cervix and oral cavity and HPV16 variants in HIV+ women. METHODS: A total of 174 HIV+ women attended an HIV+ specialized clinic in Mexico City. Cells were obtained from the oral cavity and cervix to extract DNA. Polymerase chain reaction (PCR) was used to amplify the HPV sequence with generic primers. We detected specific HPV types using the INNO-LiPA HPV Genotyping Extra II Kit (INNOGENETICS). The identification of variants was studied by sequencing the E6 gene with a Big Dye Terminator Kit and an Applied Biosystems 3500/3500xL genetic analyzer. RESULTS: HPV infection was very high in the uterine cervix (168/174, 96.6%) and oral cavity (161/174, 92.5%). The prevalence of HPV concurrent infections in the cervix and oral cavity was 155/174 (89.1%). We found hrHPVs to be more prevalent than low-risk HPVs (lrHPVs) in the oral cavity (90.2% versus 45.4%) and that infections simultaneously affected the cervix (94.3% versus 36.2%) and oral cavity (85.1% versus 20.1%). Surprisingly, only European variants of HPV type 16 were found in the uterine cervix of women and the oral cavity of all tested samples (52 oral cavity samples and 52 uterine cervix samples). CONCLUSIONS: The high prevalence of HPV, multiple infections and presence of the EP350G intravariant in both anatomical regions are strongly related to the persistence of the virus, which is fundamental for the development of cancer. Therefore, it is very important to control and monitor this high-risk population as well as implement programs for the early detection of HPV and vaccination.

Positive correlation between the frequency of micronucleated cells and dysplasia in Papanicolaou smears.

Most cancers arise in epithelial tissues and these tissues are typically the targets of the carcinogens responsible for the tumors. Exfoliated epithelial cells have traditionally been used for cancer screening by cytopathologists and these cells also can be used for biomonitoring of genotoxic effects in humans. Cervical cancer results from the progression of preinvasive precursor lesions, called low-grade squamous intraepithelial lesions (LGSILs), to high-grade squamous intraepithelial lesions (HGSILs). The gradient from low to high-grade lesions is characterized by increasing nuclear atypia and the failure of cellular differentiation in progressively more superficial levels of the epithelium. These phenotypic changes are hypothesized to be accompanied by increased genetic instability that can be documented using the micronucleus (MN) assay in exfoliated cervical cells. A retrospective study was performed to investigate the frequency of micronucleated cells in cervical smears from women at high risk for developing cervical cancer. Papanicolaou (Pap) smears from 275 women previously studied at a cancer clinic were coded and analyzed for the frequency of micronucleated cells. LGSIL, HGSIL, and invasive carcinoma smears had significantly higher frequencies than normal and ASCUS (abnormal squamous cells of undetermined origin) smears. HGSIL or severely dysplastic smears had the highest frequency of micronucleated cells (although not significantly higher than LGSIL smears), an observation that that could be useful in confirming these types of lesions. The results indicate that the MN frequency in exfoliated cervical cells may be an additional criterion for establishing cervical cancer risk.

Geographical variation in human papillomavirus prevalence in Mexican women with normal cytology.

OBJECTIVE: To determine the prevalence of human papillomavirus (HPV) infection and genotype distribution in Mexican women with similar lifestyles from two geographical regions who receive medical care from the Mexican Navy Health System, and to identify the associated sociodemographic and reproductive characteristics. METHODS: Cervical swabs from 671 women, beneficiaries of the Mexican Navy Health System, from two distinct southern coast regions of Mexico, were analyzed. Data were obtained regarding sociodemographic variables and sexual and reproductive history. For HPV detection and typing, PCR with general primers and direct sequencing were performed on extracted DNA. Association with clinical variables was evaluated. RESULTS: Most patients had a normal cytology or low-grade intraepithelial neoplasia. A high prevalence of HPV was found (43.6%), with a significant difference between the two regions studied from the southwest Pacific coast of Mexico (37.6% in Acapulco, Guerrero vs. 49.7% in Lázaro Cárdenas, Michoacán). Some differences were also found associated to HPV type distribution, particularly related to genotypes 18, 58, and 53. Factors influencing these differences could not be identified with the analysis of typical risk factors linked to the acquisition of an HPV infection. CONCLUSIONS: Regional differences in HPV prevalence and distribution show an apparent geographic boundary between the studied populations that deserves further analysis, taking into account other factors such as those related to the sexual partners.