Abstract 1779: Chronic NSAID use increases survival in PIK3CA-altered head and neck squamous cell carcinoma

Abstract

Abstract Background: PIK3CA is the most commonly altered oncogene in head and neck squamous cell carcinoma (HNSCC). Chronic non-steroidal anti-inflammatory (NSAID) use has been shown to reduce mortality in PIK3CA-mutated colorectal cancer through an unknown mechanism. In this retrospective cohort analysis, we evaluated the impact of NSAIDs on HNSCC survival, and sought a biologically plausible explanation for the observed effect. Methods: The PIK3CA status of tumor tissue was determined by FISH and next generation sequencing for 266 HNSCC patients treated at the University of Pittsburgh Cancer Institute. Cox joint proportional hazards models were used to generate multivariate projections of disease-specific (DSS) and overall survival (OS). Prostaglandin E2 (PGE2) secretion and NSAID sensitivity were then assessed in HNSCC cell lines with or without PIK3CA mutation. Results: Chronic NSAID use (≥2 days/week for ≥6 months) was associated with greater disease-specific (HR 0.24; 95% CI, 0.09 - 0.62; p = 0.0032) and overall survival (HR 0.31; 95% CI, 0.14 - 0.69; p = 0.0043) in patients whose tumors harbor PIK3CA mutation and/or amplification. Survival was unchanged by chronic NSAID use in patients with wild-type, unamplified PIK3CA. Chronic NSAID users with PIK3CA-altered tumors had an increase in estimated 5-year DSS from 25% to 72% and in OS from 45% to 78%. Benefit was independent of age, stage, and human papillomavirus (HPV) status; all of which were controlled for in the model. HNSCC cells with endogenous or engineered PIK3CA mutation secreted higher levels of PGE2 and were more sensitive to growth inhibition by NSAID treatment. Conclusions: Chronic NSAID use was associated with markedly improved survival in patients with PIK3CA-altered HNSCC, but not in those with wild-type, unamplified PIK3CA. Preclinical studies implicate the PI3K-COX-PGE2 signaling axis as a potential mediator of NSAID response. A prospective, randomized controlled trial of NSAIDs in patients with PIK3CA-altered HNSCC is warranted. Citation Format: Matthew Louis Hedberg, Noah Peyser, William Gooding, Hua Li, Toni Brand, Victor Olivas, Trever Bivona, Simion Choisea, Lin Wang, Jonas Johnson, Uma Duvvuri, Robert Ferris, Daniel Johnson, Patrick Ha, Julie Bauman, Jennifer Grandis. Chronic NSAID use increases survival in PIK3CA-altered head and neck squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1779. doi:10.1158/1538-7445.AM2017-1779