Abstract PR05: Lineage specifiers SOX2 and NKX2-1 inversely regulate lung tumor immune microenvironment

The tumor microenvironment is a critical effector of therapeutic response to diverse stimuli including immunotherapies. Lineage-specific drivers of cancer are known to dictate tumor differentiation and response to therapy, but how they influence the tumor immune microenvironment is largely unknown. SOX2 and NKX2-1 are critical regulators of lung development and cancer, with SOX2 amplifications associated with squamous lung cancer and NKX2-1 amplifications associated with lung adenocarcinoma. Here we employ and develop new genetically engineered mouse models (GEMMs) of lung cancer to interrogate the impact of SOX2 and NKX2-1 on innate immune infiltration. Squamous and adenocarcinoma GEMMs accurately recapitulate features of their human counterparts, including an enrichment of tumor-associated neutrophils (TANs) specifically in squamous lung cancer. We show that SOX2 recruits TANs, whereas NKX2-1 suppresses TANs, in the absence of histopathologic changes. SOX2 and NKX2-1 inversely regulate the neutrophil chemoattractant, Cxcl5, which is also upregulated in human squamous lung tumors. Using a novel GEMM of squamous lung cancer with a rapid latency of 3-4 months, preliminary data suggest that neutrophils can regulate adeno- to squamous transdifferentiation in vivo. Together these data reveal how lineage specifiers influence the tumor immune microenvironment, which in turn may regulate cancer cell fate. This abstract is also being presented as Poster B19. Citation Format: Gurkan Mollaoglu, Alex Jones, Anandaroop Mukhopadhyay, Jason Gertz, Kevin Jones, Eric Snyder, Trudy G. Oliver. Lineage specifiers SOX2 and NKX2-1 inversely regulate lung tumor immune microenvironment [abstract]. In: Proceedings of the AACR Special Conference: Advances in Modeling Cancer in Mice: Technology, Biology, and Beyond; 2017 Sep 24-27; Orlando, Florida. Philadelphia (PA): AACR; Cancer Res 2018;78(10 Suppl):Abstract nr PR05.