Abstract
Immune checkpoint blockade (ICB) offers an in vivo approach to activate CD8+ tumor-infiltrating lymphocytes (CD8+TILs) in cases of advanced non-small cell lung cancer (NSCLC). A large fraction of NSCLC patients is unresponsive to ICBs and relapse due to the development of dysfunctional CD8+TILs with impaired cytotoxicity. Therefore, an improved understanding of regulator(s) that favor the development of cytotoxic Teff cells over dysfunctional CD8+TILs is required for the success of ICB therapy in NSCLC patients. Here, our metaVIPER-based scRNA-seq analysis of deep CD8+ cell scRNA-seq data from 14 treatment-naïve NSCLC patients revealed that the master regulon ZEB2 may drive CD8+ differentiation along the cytotoxic effector trajectory in NSCLC tumors. In vitro, ZEB2 acts downstream of T-bet to stimulate lung tumor-reactive Teff cell differentiation. This T-bet/ZEB2 axis displays immunotherapeutic effects on KP.SIY lung tumors independent of ICB therapy and mediates the therapeutic effects of murine serum albumin-fused IL-2 + IL-12 combination immunotherapy (IL2-MSA + IL12-MSA) in mice. IL2-MSA + IL12-MSA operates through a parallel STAT4/FOXO1-mediated mechanism that promotes CD8+TIL T-bet/ZEB2 expression and lung tumor-reactive Teff cell differentiation. In conclusion, immunotherapeutic regimens that support ZEB2 activity in CD8+ cells may show promise in NSCLC patients.