CD9 and gastric cancer: Moreover, expression of CD9, COL3A1, COL4A1 were related to prognosis of the patients through univariate Cox analysis and we finally determined that peritoneal metastasis, lnc-TRIM28-14 and COL3A1 expression could be independent risk factors for assessing the prognosis of patients with gastric cancer using multivariate Cox analysis (Table S8).