Notch 1/2/3 mutation as a potential biomarker for immunotherapy in smokers with non-small cell lung cancer via increasing tumor mutational burden

Background: Smoking status have been discovered to be associated with the response of anti-PD-1/PD-L1 treatment in advanced non-small cell lung cancer (NSCLC), on account of the smoking-induced higher tumor mutational burden (TMB). However, merely partial smokers with NSCLC exhibit high TMB and respond to anti-PD-1/PD-L1 therapy. The underlying signalling pathway that involved in the accumulation of mutational burden and response to immunotherapy in smokers with NSCLC has not been clarified. Methods: Data from Rizvi study (n = 240, nivolumab, tissue-sample NGS) and OAK study (n = 642, atezolizumab vs. docetaxel, blood-sample NGS) was retrieved and analysed as training cohorts, followed with validation in our independent NSCLC cohort (n = 44, anti-PD-1/PD-L1, blood-sample NGS). In survival analysis, Kaplan-Meier curves were compared by log-rank test, and the hazard ratio (HR) was determined through a multivariable Cox regression model. Results: In Rizvi cohort, mutation of Notch 1/2/3 was associated with higher TMB in smokers with NSCLC (P with immunotherapy (P = 0.018; HR, 0.28, 95% CI, 0.10-0.81). No association of Notch 1/2/3 status and PFS was observed in smokers with NSCLC treated with chemotherapy (P = 0.80; HR, 0.92, 95% CI, 0.47-1.78). We further validated these results in our independent cohort. Similar upregulation of TMB was observed in the Notch1/2/3-mutated smokers with NSCLC, and Notch1/2/3mut improved DCR (100% vs. 41.2%, P = 0.065) and significantly prolonged PFS (P = 0.046; adjusted HR, 0.12, 95% CI, 0.01-0.96). Conclusions: Notch1/2/3 mutation may serve as a novel predictor of response to anti-PD-1/PD-L1 treatment in smokers with NSCLC via upregulating TMB. Citation Format: Xiaohua Hong, Aijun Shen, Yu Xu, Chengcheng Li, Guoqiang Wang, Li Liu, Chuang Qi. Notch 1/2/3 mutation as a potential biomarker for immunotherapy in smokers with non-small cell lung cancer via increasing tumor mutational burden [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4011.