Gene expression profile can also assess the functional state of TILs: in a prospective setting, IMpower150 study of PDL-1 inhibitor atezolizumab used the biomarker CD8+ Teff gene signature, defined by PDL-1, CXCL9, and IFN-γ mRNA expression from baseline tumor tissue (87). This evidence concerns the gene CXCL9 and neoplasm.