Screening and verification of anti-programmed death-ligand 1 immunotherapy-sensitive genes in lung squamous cell carcinoma based on bioinformatics

PurposeThis study aimed to identify genes associated with sensitivity to anti-programmed death-ligand 1 (PD-L1) immunotherapy in lung squamous cell carcinoma (LUSC) using bioinformatics approaches and to validate their functional relevance through in vitro experiments.MethodsTranscriptomic datasets from The Cancer Genome Atlas were analyzed to screen candidate genes, and UBE2C was identified as a key target. Functional enrichment analysis (Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) was performed to explore its potential biological roles. To investigate its regulatory effects, UBE2C was overexpressed or silenced in LUSC cells, with or without PD-L1 inhibitor treatment. Real time-quantitative polymerase chain reaction and Western blot were used to assess changes in gene/protein expression and pathway activation. Enzyme-linked immunosorbent assay and lactate dehydrogenase assays were employed to evaluate cytokine secretion (interferon (IFN)-γ, interleukin (IL)-2) and cytotoxicity. Additionally, immunofluorescence was used to examine UBE2C and PD-L1 co-expression in patient tissues stratified by PD-L1 expression levels.ResultsUBE2C expression was significantly higher in PD-L1 high-expression tissues than in low-expression tissues at both messenger RNA and protein levels. Compared with control groups, UBE2C overexpression activated the AKT/PI3 K pathway and increased IFN-γ and IL-2 secretion, whereas knockdown produced the opposite effect. Combined treatment with UBE2C overexpression and a PD-L1 inhibitor further enhanced cytokine release and cytotoxicity relative to PD-L1 inhibitor alone. Immunofluorescence analysis confirmed the co-localization of UBE2C and PD-L1 in tissues with high PD-L1 expression.ConclusionUBE2C was identified as a gene associated with increased sensitivity to anti-PD-L1 immunotherapy in LUSC. Functional experiments suggest that UBE2C may enhance anti-tumor immune responses and improve immunotherapy efficacy, providing a potential biomarker and therapeutic target for personalized treatment.