COL1A1 and neoplasm: Additionally, p28 co-administration with iRGD and 5-FU, or therapy with p28 and 5-FU, dramatically decreased the expression of the CoL1a1 and CoL1a2 genes in the tumor tissues when compared with the mice receiving solo therapy with p28 or 5-FU (P<0.05 and P<0.001, respectively).