COL4A1 and neoplasm: During this process, we analyzed the differences in the expression of all genes related to normal-tumor tissues among the selected gastric tissue types with Match TCGA normal and GTEx data and found that all the hub genes, including ITGB1, COL1A1, COL1A2, COL4A1, FN1, COL6A3, THBS2, and THBS1, were significantly upregulated in GC tissues compared to normal tissues in this validated data series (Supplementary Fig. 5).