Abstract 4163: Blockade of the interleukin-1 signaling pathway overcomes erlotinib resistance in head and neck cancer cells

Abstract

Abstract The EGFR tyrosine kinase inhibitor erlotinib has demonstrated poor clinical response rates for head and neck squamous cell carcinoma (HNSCC) to date and the majority of respondents acquire resistance to erlotinib relatively quickly. Our previous data has shown that erlotinib activated interleukin-1 (IL-1) expression and signaling in HNSCC cells in vitro. We therefore investigated if upregulation of IL-1 signaling is involved in erlotinib resistance in HNSCC cells. We compared gene expression profiles of erlotinib-resistant (ER) and the parental erlotinib-sensitive (ES) HNSCC cell lines and observed a deregulation of the IL-1 signaling pathway in ER versus ES-HNSCC cells using microarray enrichment analysis. Secretion of IL-1 alpha (IL-1α) and IL-1 beta (IL-1β) were not significantly different in ER-SQ20B and ER-CAL 27 cells compared to their respective ES-cells, however secretion of the IL-1 receptor antagonist (IL-1RA) was significantly reduced in ER-cells compared to ES-cells. Blockade of IL-1 signaling using a recombinant IL-1R antagonist (anakinra) was able to significantly suppress the growth of ER-SQ20B but not ES-SQ20B xenografts as a single agent and in combination with erlotinib. ER-SQ20B xenografts treated with anakinra with or without erlotinib were found to be less vascularized (as determined by CD31 staining) than ER-SQ20B xenografts treated with water or erlotinib. Altogether, blockade of the IL-1 pathway using anakinra overcame erlotinib resistance in HNSCC xenografts and may represent a novel strategy to overcome EGFR inhibitor resistance for the treatment of HNSCC patients. Citation Format: Andrean L. Simons, Aditya Stanam, Katherine N. Gibson-Corley. Blockade of the interleukin-1 signaling pathway overcomes erlotinib resistance in head and neck cancer cells [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 4163. doi:10.1158/1538-7445.AM2017-4163