TGFB1 and cancer: The TGFβ1 molecule is a crucial component in understanding tumor-stromal interactions: although produced by tumor cells, it is overexpressed by stromal cells mainly at the invasive front area of human PDAC [23]; moreover, in an experimental PDAC mouse model TGFβ1 was shown to mediate cancer cell derived Cxcr2 stimulatory effects on pancreatic fibroblasts to express Ctgf, which is greatly involved in PDAC progression [21].