COL5A1 and gastric cancer: Moreover, the stepwise addition of these two genes as covariates to the CO1A1, COL5A1, and ITGA4 multivariate Cox model tremendously increased the hazard ratio for the poor prognostic impact of CAF infiltration, which suggested a stage and CAF dependent role for EMILIN1 and TSPAN9 in gastric cancer (Table 4).