Hypoxia‐based critical gene biomarkers as prognostic reporters for gastric adenocarcinoma

Abstract Background Gastric cancer is the most common malignant tumour of the digestive system, yet there is a lack of reported prognostic biomarkers for STAD patients. Methods Transcriptomic expression data of STAD from GEO database, single cell sequencing data from OMIX gastric cancer database. Conservative molecular typing of gastric cancer was constructed using non‐negative matrix factorization (NMF). The abundance of 28 immune cells in the tumour samples was assessed using ssGSEA. The R package “oncoPredict” was used to predict chemotherapy response. TIDE website for immunotherapy response prediction. Finally, single cell analysis was performed to clarify the specific type annotation of STAD cells and to analysis their spatial expression. Results Hypoxia‐score demonstrated excellent prognostic discrimination in TCGA gastric cancer samples. Among multiple deconvolution‐based algorithms for immune infiltration, Hypoxia‐score presented a general immunosuppressive efficacy across multiple datasets, as evidenced by a broad negative correlation with immune cell infiltration. By the likelihood that each group may have specific drug sensitivity to multiple chemotherapeutic and targeted agents. Results showed that high‐risk scoring patients were more sensitive to Staurosporine, Sabutoclax, and AZD8055, while low‐risk patients were more sensitive to Bortezomib, Dactinomycin, Docetaxel, Daporinad, Sepantronium, and bromide. In the immunotherapy cohort, the Hypoxia‐score presented the ability to discriminate for immunotherapy efficacy. The distribution of Hypoxia‐score in single‐cell descending space was calculated using AddModuleScore and was found to be distributed across the various cell types annotated in the single‐cell analysis. It is suggested that various cells in the tumour microenvironment are involved in hypoxia gene set processes to varying degrees. Conclusion The Hypoxia‐score proves to be a valuable tool for assessing the prognosis of gastric cancer patients and guiding drug treatments, providing significant guidance for clinical diagnosis and treatment in the context of gastric cancer.