FIG 1.

Summary of potential biomarkers under investigation for predicting response to therapy with immune checkpoint inhibitors. Representative candidates for biomarkers in tumor cells, the tumor microenvironment, and the circulation are depicted. In addition, clinical and host factors under investigation are included. B2M, beta-2 microglobulin; CTC, circulating tumor cell; ctDNA, circulating tumor DNA; GEP, gene expression profile; IFN, interferon; JAK1/2, Janus kinase 1/2; MMR, mismatch repair; ncRNA, noncoding RNA; NK, natural killer; PD-L1, programmed cell death ligand; TAM, tumor-associated macrophage; TCR, T-cell receptor; TMB, tumor mutational burden; TIL, tumor-infiltrating lymphocyte; Treg, regulatory T cell. Created with BioRender.⁴⁴