Abstract 6121: Correlation of tumor immune microenvironment status and driver genes alterations in Chinese non-small-cell lung cancer patients

Abstract Background: Patients with different driver genes show a variety of immunotherapy efficacy for non-small-cell lung cancer (NSCLC). In addition to PD-L1, the evaluation of the immune microenvironment contributes to a deeper understanding of the mechanisms of immunotherapy resistance. Methods: Tumor tissues from 2674 NSCLC patients were collected. Genetic alterations were profiled using targeted next-generation sequencing with 733 cancer-related genes panel. Immunohistochemistry was used to evaluate the PD-L1 tumor proportion score, (TPS) expression on the surface of tumor cells. Tumor-infiltrating immune cells of 120 tumor samples were labeled with multiple immunofluorescence staining. Results: Overall, CD8+ T cell infiltration level was negatively associated with both EGFR copy number gain (CNG, p < 0.001) and ERBB2 CNG (p = 0.021). Also, the presence of EGFR or ERBB2 CNG was related with fewer natural killer cell infiltration (EGFR: p < 0.001; ERBB2: p = 0.036) and a lower M1/M2 tumor-associated macrophages ratio compared to wild-type tumors (EGFR: p = 0.051; ERBB2: p = 0.036), suggesting a relatively weaker anti-tumor ability. In addition, we noted that KRAS CNV was negatively related to M2 macrophages (p = 0.027). Patients carrying ALK translocation (p < 0.001), ROS1 translocation (p = 0.006), KRAS mutations (p < 0.001) and MET (p < 0.001) mutations had the elevated PD-L1 TPS expressions, while those harboring EGFR (p < 0.001) and ERBB2 mutations (p = 0.001) had lower PD-L1 expression. Compared to the other EGFR mutations, PD-L1 expression in EGFR CNG tumors was higher, and no significant differences were found between CNG and other types of mutation in patients harboring ERBB2, KRAS, MET alterations. Conclusion: NSCLC patients with EGFR CNG and ERBB2 CNG had fewer invasion of cytotoxic T cells and NK cells and a lower M1/M2 macrophages ratio. EGFR CNG may intensively modify the tumor immune microenvironment, which is a possible mechanism contributing to EGFR-TKI resistance. Citation Format: Jindong Guo, Liwen Xiong, Haibin Yuan, Mengna Hu, Bei Zhang, Ding Zhang. Correlation of tumor immune microenvironment status and driver genes alterations in Chinese non-small-cell lung cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6121.