Abstract 4785: A pilot study of the association and prevalence of the human papillomavirus (HPV) in non-small cell lung cancer (NSCLC).
Authors: Mehra Ranee , Egleston Brian , Yang Donghua , Scott Walter , Borghaei Hossein , Ragin Camille 
Published: August 2014

Introduction: Given its potent oncogenic properties, the prevalence of HPV, and the proximity of the bronchial epithelia to the oral cavity we hypothesized that HPV infection may have a role in the causality of NSCLC in patients without a significant smoking history. In Asia, studies report rates of HPV infection in NSCLC tumors as high as 80%. The expression of p16 in head and neck cancer is a reliable surrogate for HPV, and its presence portends a good prognosis. The goal of our study was to analyze archival lung tissue for the presence of p16 expression and HPV infection among never smokers or &lt; 10 pack year smoking patients with NSCLC.

Methods: Surgical specimens from never/light smokers was identified in the Fox Chase Cancer Center Biosample Repository. A tissue microarray was constructed for immunohistochemistry analysis on the quantitative platform, AQUA, for p16. DNA was also extracted from archival tissue for assessment of p16 status. Real-time PCR and reverse hybridization (INNO-LiPA) was utilized to detect evidence of HPV genes in tumor samples. In order to determine if the viral genome was episomal or integrated, PCR to determine E2:E6 ratios were employed. The association of p16 expression and HPV infection was assessed.

Study results: Available tissue included 36 NSCLC surgical specimens from never/light smokers (1995-2009). Patient characteristics were: 28 female, age range: 47-84, Histology: adenocarcinoma (31, 86%), adenosquamous (3, 8%), and squamous (2, 6%). TNM Stage: T1 (5, 14%), T2 (27, 75%), T3 (1, 3%), T4 (1, 3%), N0 (18, 50%), N1 (8, 22%), N2 (8, 22%), N3 (1, 3%), M1 (2, 5.5%). The p16 AQUA score range: 91-7733. A natural cut point occurred at 3000 with 25 low (p16-) and 8 high (p16+) expressers. AQUA score correlated with standard IHC H score (p=0.0005). There was no significant relationship between p16 level and gender, T or N stage. p16+ was associated with a trend towards inferior survival (HR 2.18, p=0.157). Evidence of HPV 16 and 18 viral DNA, as measured by real-time PCR and reverse hybridization (INNO-LiPA) was detected in 4 samples; 16 (2, 5.5%), 18 (2, 5.5%). Additional high risk oncogenic HPV viruses which were also detected included HPV 35, 52 and 53. Based on the calculation of HPV 16 E2:E6 ratios, both specimens (1 male, 1 female) with evidence of HPV16 infection also had evidence of genome integration of HPV16 DNA. There was no association between HPV infection and p16 expression.

Conclusions: In our series of NSCLC among never or light smokers, the rate of HPV 16 viral infection and integration was 5.5%. Notably, all HPV 16 infected tumors had integrated genomes; a novel finding among NSCLC tumors in the Western population. In our small series, p16+ status was not associated with HPV infection. Future study of the potential role of HPV in the pathogenesis of NSCLC warrants exploration, including an assessment of genomic integration of additional strains of high risk HPV DNA.

Citation Format: Ranee Mehra, Brian Egleston, Donghua Yang, Walter Scott, Hossein Borghaei, Camille Ragin. A pilot study of the association and prevalence of the human papillomavirus (HPV) in non-small cell lung cancer (NSCLC). [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4785. doi:10.1158/1538-7445.AM2013-4785