Detection of serum biomarkers of HPV-16 driven oropharynx and oral cavity cancer in Brazil.

BACKGROUND: HPV-16 driven oropharynx/oral cavity squamous cell carcinomas prevalence varies globally. We evaluated the presence of HPV-16 ctDNA and HPV-16 E6 antibodies in samples obtained from participants treated at the Instituto do Cancer do Estado de Sao Paulo, ICESP, and from whom tumoral HPV DNA, HPV-16 E6*I mRNA, and p16INK4a status was also accessed. METHODS: HPV was genotyped by PCR-hybridization. All HPV DNA positive and ∼10 % HPV DNA negative cases underwent p16INK4a immunohistochemistry and E6*I RNA testing using a multiplex bead based protocol. HPV-16 ctDNA and anti-E6 antibodies were assessed by ddPCR (digital droplet PCR) and multiplex serology, respectively. RESULTS: The prevalence of HPV-16 in oropharynx carcinoma (OPC) cases was low (8.7 %) when considering solely HPV-16 DNA detection, and even lower (5.2 %) when taken into consideration the concomitant detection of HPV-16 E6*I RNA and/or p16INK4 (HPV-16 attributable fraction - AF). None of the oral cavity cancer (OCC) cases were detected with HPV-16 DNA. HPV-16 ctDNA was more commonly detected than HPV-16 E6 antibodies (29.8 % versus 10.6 %). Both serum biomarkers attained 100 % sensitivity of detecting HPV-16 AF OPC, however the specificity of the HPV-16 anti-E6 biomarker was higher compared to ctDNA (93.2 % versus 75.0 %). Finally, when both HPV-16 ctDNA and anti-E6 biomarkers were considered together, the sensitivity and specificity for HPV-16 OPC detection was 100 % and about 70 %, respectively, independently of analyzing HPV-16 DNA positive or HPV-16 AF tumors. CONCLUSIONS: Our findings corroborate that serum biomarkers are highly sensitive and specific biomarkers for detection of HPV-associated OPC.

Human Papillomavirus 16 Lineage A Variants Associated With Persistent Genital Infections in Men: The HPV Infection in Men (HIM) Study.

BACKGROUND: Human papillomavirus (HPV) 16 non-A lineage variants have higher carcinogenic potential for cervical cancer. HPV-16 variants natural history among males is not established. We evaluated HPV-16 variants prevalence and persistence in the external genitalia of men enrolled in the prospective HPV Infection in Men (HIM) Study. METHODS: The HIM Study included men from the United States, Brazil, and Mexico. HPV-16 variants were distinguished using polymerase chain reaction sequencing. The prevalence of HPV-16 variants was assessed, and associations with infection persistence were estimated. RESULTS: We characterized the HPV-16 variants for 1700 genital swab samples from 753 men and 22 external genital lesions in 17 men. The prevalence of HPV-16 lineages differed by country and marital status (P < .001). Overall, 90.9% of participants harbored lineage A variants. The prevalence of non-A lineages was heterogenous among countries. HPV-16 lineage A variants were associated with a 2.69-fold increased risk of long-term persistent infections compared with non-A lineages. All high-grade penile intraepithelial neoplasia harbored lineage A variants and occurred in the context of long-term persistent infections with the same variants. CONCLUSIONS: The prevalence and persistence of HPV-16 variants observed at the male external genitalia suggest differences in the natural history of these variants between men and women, which may be associated with intrinsic differences in the infected genital epithelia.

Prevalence and persistence of HPV-16 molecular variants in the anal canal of men: The HIM study.

BACKGROUND: HPV-16 causes approximately 90% of anal canal (AC) cancers worldwide. This study aimed to evaluate the prevalence and persistence of HPV-16 genetic variants in the AC of men from three different countries (Brazil, Mexico and United States) and to further identify sociodemographic and behavioral factors associated with these infections. METHODS: Participants from the multinational prospective HPV Infection in Men (HIM) Study who had at least one HPV-16 positive AC swab were included. Characterization into HPV-16 genetic variants was successfully performed by PCR-sequencing in 95.6% (217/227) samples and these were classified into HPV-16 lineages and sublineages. RESULTS: We observed higher prevalence of lineage A variants, mainly from A1 sublineage, in all countries. Non-A lineage variants were mostly detected in men from Brazil, where higher diversity of sublineage variants was detected during follow-up. Compare to men detected with Non-A HPV-16 lineage variants, men infected with lineage A reported a higher lifetime number of female sexual partners. Finally, a significantly higher prevalence of Non-A lineage variants was observed among men who have sex with men (MSM) with a transient HPV-16 AC infection (p = 0.033), but no significant differences regarding variants lineages and persistence status were observed when stratified by country, self-reported ethnicity or age. CONCLUSIONS: Our data extend previous reports which indicate that globally HPV-16 variants are unevenly distributed, and contribute further to studies of the natural history of AC HPV infections in men.