Immunogenetic polymorphisms predict therapeutic efficacy and survival outcomes in tumor patients receiving PD-1/PD-L1 blockade.

Abstract

While immune checkpoint inhibitors (ICIs) demonstrate remarkable clinical responses, only a small subset of patients obtains benefits. Genes linked to the tumor immune system are confirmed to be critical for the treatment of ICIs, and their polymorphisms can contribute to ICI efficacy. Here, we examined the potential of immunogenetic variations to predict the efficacy and survival of the PD-1/PD-L1 blockade. Cancerous patients receiving PD-1/PD-L1 blockade were recruited and followed up. Pivotal genes related to tumor-immunity were filtered through a protein-protein interaction network and the degree algorithm in Cytoscape. Finally, 39 genetic variants were genotyped through multiplex genotyping assays. Association analyses between variants and ICI efficacy and progression-free survival (PFS) were performed. Overall, 318 patients were ultimately enrolled. Hence, three immunogenetic variants were identified as predictors of PD-1/PD-L1 blockade response. Mutant alleles from ATG7 rs7625881, CD274 rs2297136, and TLR4 rs1927911 were all at increased risk of tumor progression following ICI therapy (OR: 1.475, 1.641, 1.462, respectively; P value: 0.028, 0.017, 0.027, respectively). Significant immunogenetic variants also attained similar trends in the PD-1 blockade, lung cancer, or lung cancer using PD-1 blockade subgroups. Furthermore, the mutant genotypes of CD274 rs2297136 (GG as the reference: HR: 0.50 (95%CI: 0.29-0.88), P value: 0.015) and TLR4 rs1927911 (AA as the reference: HR: 0.65 (95%CI: 0.47-0.91), P value: 0.012) indicated poorer PFS and were both independent prognostic factors. Immunogenetic polymorphisms, including ATG7 rs7625881, CD274 rs2297136, and TLR4 rs1927911, were first identified as potential predictors of response to PD-1/PD-L1 blockade in tumor patients.