Abstract 380: WNT signal pathway activation correlates with innate resistant to immune checkpoint therapies in NSCLC

Background: Immune checkpoint inhibitors targeting the programmed cell death-1 receptor (PD-1) improve survival in a subset of patients with NSCLC. There are still lots of patients could not reach the clinical benefit, even though with the positive expression of the programmed cell death 1 ligand 1 (PD-L1). Here, we aimed to research the immune resistance mechanism in NSCLC. Methods: The genomic data and clinical data of the discovery cohort was obtained from The Cancer Genome Atlas (TCGA). The clinical data of validation cohort in NSCLC treated by immunotherapy was retrospective collected. And tissue from patients with NSCLC were performed to whole exome sequencing in a College of American Pathologists-certified and Clinical Laboratory Improvement Amendments-accredited lab. Results: Activation of WNT signaling was inferred that somatic mutations or somatic copy number alterations in WNT signaling elements including APC, WNT16, AXIN2, WNT4, AXIN1, CTNNB1, BCL9L and SMAD4. Two cohort have been enrolled in this study, the discovery cohort from TCGA, and the validation cohort from the Chinese patients with NSCLC. The frequency of WNT pathway alterations from the TCGA cohort was 16%, and which was represented mutually exclusive molecular subsets. In TCGA cohort, activating alteration WNT signaling were associated with shorter median PFS (18.8 vs 3.9 months, p=0.036, HR=0.24 (0.09-0.68)). Conclusions: Mutations predicted to activate the WNT pathway were associated with innate resistance to immune checkpoint blockade in NSCLC Citation Format: Dian Ren, Bo Zhang, Renwang Liu, Fuyu Gong, Yuezong Bai, Wenzhuan Xie, Huandong Huo, Hao Zhang, Zuoqing Song. WNT signal pathway activation correlates with innate resistant to immune checkpoint therapies in NSCLC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 380.