Fig. 3
From: Biomarkers for predicting efficacy of PD-1/PD-L1 inhibitors
Mechanisms of main biomarkers predicting efficacy of PD-1/PD-L1 inhibitors. Firstly, PD-L1 status reflects adaptive immune resistance which is therapeutic target of PD-1/PD-L1 inhibitors. Mismatch repair deficiency (dMMR) and high microsatellite instability (MSI-H) correlates strongly with high tumor mutational burden (TMB). In the meanwhile, TMB enhances the immunogenicity. Thirdly, tumor infiltrating lymphocyte (TIL) represents potential immune surveillance which could be reactivated by agents. Specific gut microbiota promotes differentiation of T cell, as well as lymphocyte homing and recirculation. Besides, peripheral CD14+CD16−HLA-DRhi monocyte promotes migration of T cell to tumor bed. Lastly, variation of circulating tumor DNA (ctDNA) and PD-L1+ circulating tumor cell presents effect of agent in early stage