Polymorphisms in Cytotoxic T-lymphocyte Associated Antigen 4 Gene Does Not Affect sCytotoxic T-lymphocyte Associated Antigen 4 Levels in Human Papillomavirus-Infected Women with or without Cervical Cancer

Abstract

Background: Cervical cancer (CaCx) is the second most common cancer in Indian women. Cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) + 49 AA polymorphism is known to be associated with CaCx. Current attempt is to use immunotherapy for the treatment of metastatic melanoma and metastatic castration-resistant prostate cancer, i.e., blocking of CTLA-4 using a fully human monoclonal CTLA-4 antibody to disrupt its inhibitory signal. This allows the CTLs to destroy the cancer cells. There is no information available on the soluble level of CTLA-4 on which the immunotherapy is targeted. This is specifically in Indian population including cases with CaCx. Objective: The aim of this study is to evaluate the levels of soluble CTLA-4 (sCTLA-4) in human papillomavirus (HPV)-infected women with or without CaCx and their association with the polymorphism at CTLA-4 + 49 A/G and CTLA-4 −318 C/T genotypes. Materials and Methods: This is an exploratory case–control study involving two groups of HPV-infected women, the cases were with invasive CaCx and the control group was women with the healthy cervix. sCTLA-4 levels were measured using ELISA in 92 CaCx cases and 57 HPV-positive women with the healthy cervix. Results: Both cases and controls have similar sCTLA-4 levels. Comparison of CTLA-4 + 49A/G and −318 C/T genotypes with sCTLA-4 levels among cases and control also did not show any statistically significant difference. Conclusion: The present study suggests sCTLA-4 levels are not affected by a polymorphism at + 49 A>G CTLA-4. Hence, levels of CTLA-4 are similar in both CaCx cases and control group.