Comparative Analysis of the Antitumor Immune Profiles of Paired Radiotherapy-naive and Radiotherapy-treated Cervical Cancer Tissues

Abstract

Background/Aim: This study aimed to elucidate the effect of radiotherapy on expression of immune response-related genes in cervical cancer tissues. Materials and Methods: Tumor tissues were obtained from 16 patients with cervical cancer before initiation of radiotherapy and after treatment with 10 Gy X-rays, delivered in five fractions. Expression of 730 immune response-related genes was assessed using an nCounter PanCancer Immune Profiling Panel (NanoString Technologies. Seattle, WA, USA). Results: Of the 730 genes examined, 41 showed significant changes (fold change of >1.5 or <0.66) in expression in post-radiotherapy samples (28 up-regulated and 13 down-regulated). Analysis of immune cell type-specific genes suggested predominant up-regulation of those related to innate immunity postradiotherapy. Interestingly, cytotoxic T-lymphocyte-associated protein (CTLA4), a key negative regulator of T-cell activation, was marked down-regulated in 93.7% of patients, with an average fold-change of 2.0. Conclusion: To our knowledge, this study is the first to show down-regulation of CTLA4 in clinical cervical cancer tissues after treatment with radiotherapy.