title: HPV genotyping and p16 expression in Xingu Indigenous Park, Brazil.
abstract: The association between high-risk human papillomavirus (HPV) genotypes and p16 expression in indigenous women from the Xingu Indigenous Park, Brazil, was unknown. This study evaluated p16 expression in women with a histological diagnosis of cervical intraepithelial neoplasia (CIN) 3 or higher and correlated this expression with HPV genotypes to determine possible discrepancies in the expression of this marker. We evaluated 37 previously collected samples with different HPV genotypes and high-grade lesions diagnosed based on cytology, histology, and colposcopy. Immunohistochemical analysis was performed using paraffin-embedded tissue sections and the CINtec® Histology Kit. p16 protein expression was investigated by immunostaining with an anti-p16 antibody. HPV genotyping was performed by reverse hybridization. The age of the study population ranged from 22-75 years (43.81 ± 15.89 years) and parity ranged from 1-11 (5.92 ± 2.58). Thirteen different HPV genotypes were found using the INNO-LiPA kit. Single and multiple infections by HPV were found with prevalence of single infections (P = 0.029). Comparison between HPV genotype and simple or multiple infections was highly significant; it was observed more HPV 52 followed by HPV 16 in single infections (P < 0.001). p16 expression was predominantly diffuse, which was observed in 91.7% of lesions, whereas 8.3% were focal (P < 0.001). HPV 52, HPV 16 and 31 were the most prevalent HPV types in high-grade CIN in these indigenous women. Diffuse p16 expression in high-grade CIN was not influenced by the viral genotype; however, more studies are necessary to further our understanding of this restricted group.
authors.affiliation: Núcleo de Prevenção de Doenças Ginecológicas, Departamento de Ginecologia, Universidade Federal de São Paulo, São Paulo, SP, Brasil valgfreitas@yahoo.com.br.
authors.forename: V G
authors.initials: VG
authors.lastname: Freitas
authors.affiliation: Departamento de Patologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
authors.forename: G R
authors.initials: GR
authors.lastname: Focchi
authors.affiliation: Departamento de Medicina Preventiva, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
authors.forename: E R
authors.initials: ER
authors.lastname: Pereira
authors.affiliation: Instituto de Medicina Tropical da Universidade de São Paulo, São Paulo, SP, Brasil.
authors.forename: J E
authors.initials: JE
authors.lastname: Levi
authors.affiliation: Núcleo de Prevenção de Doenças Ginecológicas, Departamento de Ginecologia, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
authors.forename: N M G
authors.initials: NM
authors.lastname: Speck
authors.affiliation: Núcleo de Prevenção de Doenças Ginecológicas, Departamento de Ginecologia, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
authors.forename: J C
authors.initials: JC
authors.lastname: Ribalta
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000096:biosynthesis* / Q000235:genetics; D001938:Brazil; D003127:Colposcopy; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D005786:Gene Expression Regulation; D005838:Genotype; D052162:Human papillomavirus 16 / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity; D058952:Human papillomavirus 31 / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity; D006801:Humans; D008875:Middle Aged; D030361:Papillomavirus Infections / Q000235:genetics* / Q000473:pathology / Q000821:virology; D002578:Uterine Cervical Dysplasia / Q000235:genetics* / Q000473:pathology / Q000821:virology
chemical_list: D014408:Biomarkers, Tumor; D019941:Cyclin-Dependent Kinase Inhibitor p16