The association of genomic alterations with PD‐L1 expression in Chinese patients with EGFR/ALK wild‐type lung adenocarcinoma and potential predictive value of Hippo pathway mutations to immunotherapy

Abstract

BackgroundThe study focuses on PD‐L1 expression as an essential biomarker for gauging the response of EGFR/ALK wild‐type NSCLC patients to FDA‐approved immune checkpoint inhibitors (ICIs). It aims to explore clinical, molecular, and immune microenvironment characteristics associated with PD‐L1 expression in EGFR/ALK wild‐type lung adenocarcinoma patients eligible for ICI therapy.MethodsIn this retrospective study, tumor samples from 359 Chinese EGFR/ALK wild‐type lung adenocarcinoma patients underwent comprehensive evaluations for PD‐L1 expression and NGS‐targeted sequencing. The investigation encompassed the analysis and comparison of clinical traits, gene mutations, pathways, and immune signatures between two groups categorized by PD‐L1 status: negative (TPS < 1%) and positive (TPS ≥ 1%). Additionally, the study explored the link between genomic changes and outcomes following immunotherapy.ResultsHigh tumor mutational burden correlated significantly with PD‐L1 positivity in patients with EGFR/ALK wild‐type lung adenocarcinoma. Gene alterations, including TP53, KRAS, and others, were more pronounced in the PD‐L1 positive group. Pathway analysis highlighted higher frequencies of alterations in pathways like RTK/RAS, p53, and Hippo in PD‐L1‐positive patients. The Hippo pathway's relevance was confirmed in separate immunotherapy cohorts, associated with better outcomes. In terms of immune cell infiltration, Hippo mutants exhibited higher levels of CD68+PD‐L1+ macrophages, CD8+ T cells, and CD8+PD‐1− T cells.ConclusionsThis study offers insights into genomic features of Chinese EGFR/ALK wild‐type lung adenocarcinoma patients based on PD‐L1 expression. Notably, Hippo pathway alterations were linked to improved immunotherapy outcomes. These findings suggest connections between the Hippo pathway and PD‐L1 expression, warranting further clinical and functional investigations. The research advances our understanding of PD‐L1 expression's genomic context and immunotherapy response in EGFR/ALK wild‐type lung adenocarcinoma.