Combined protein and transcriptomics identifies DCTPP1 as a putative biomarkers for predicting immunotherapy responsiveness in gastric cancer patients.

This study aimed to screen the changes after overexpression of dCTP pyrophosphatase 1 (DCTPP1) in human gastric adenocarcinoma cells (AGS) cells by proteome and transcriptome sequencing. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis were performed to explore the functional significance of the differentially expressed DCTPP1 in gastric cancer (GC). Cell Counting Kit-8 (CCK-8) assay was used to detect the proliferation of cells. Western blot was used to detect the expression of proteins. A total of 28 genes that were significantly associated with DCTPP1 overexpression and had prognostic value were screened by Cox regression analysis. The results of gene set enrichment analysis showed that the genomes of patients with subtype A exhibited significant enrichment in pathways such as DNA repair, pyrimidine synthesis, and glucose metabolism. The tumor immune dysfunction and exclusion and The Cancer Immunome Atlas databases showed that patients with type A GC were better candidates for immunotherapy than patients with type B GC. Furthermore, the CCK-8 assay indicated significantly enhanced proliferative activity after overexpressing DCTPP1 in AGS cells, corroborating the findings from the bioinformatic analysis. The data suggest a potential association between DCTPP1 expression and both the prognosis of GC patients and the efficacy of immunotherapy. These findings offer valuable insights for the potential optimization of therapeutic strategies in gastric cancer.