Peripheral myeloid-derived suppressor cell(MDSC) as a hallmark of positive responder in Non-Small Cell Lung Cancer(NSCLC) patient treated with anti-PD-1/PD-L1 therapy
Su-Myeong Park1,2,Sang-Uk Seo1,2,Seung-Yong Seong1,2,3,Sang-Jun Ha4,Hye Ryun Kim5,Je-In Youn1,2*
1Wide River Institute of Immunology, Seoul National University College of Medicine, Hongcheon, Republic of Korea
2Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
3Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Republic of Korea
4Department of Biochemistry, College of Life Science & Biotechnology, Yonsei University, Seoul, Republic of Korea
5Department of Internal Medicine, Division of Medical Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Republic of Korea
In recent years, immune-checkpoint regulators such as CTLA-4(Cytotoxic T-Lymphocyte Associated Protein4) and PD-1(Programmed cell death protein1) have been widely applied to target of cancer immunotherapy. Nivolumab, known as humanized IgG4 anti-PD-1 monoclonal antibody, has been spotlighted as an effective therapy in several types of cancer. However, its high market price and individual differences of drug reactivity limited its common usage. Although, many researchers have tried to find out the predictive biomarker for the therapy; IHC-based PD-L1 expression in tumor cells or tumor infiltrating cells, the prediction accuracy is not high enough to solidify the diagnosis. Recent studies show that myeloid-derived suppressor cell(MDSC) as a heterogeneous group of myeloid progenitors with immunosuppressive function could be used as one of the promising biomarker candidate for cancer immunotherapies. Therefore, here we checked and compared the peripheral lymphocyte and MDSC population between positive and negative responder for anti-PD-1/PD-L1 therapy. After third cycle of the therapy, MDSC ratio was significantly decreased in positive responder group. The cut-off value of peripheral MDSC ratio based on the clinical data is expected as a reliable biomarker for positive responder of anti-PD-1/PD-L1 therapy.