TGFB1 and neoplasm: On the other hand, other studies have demonstrated that KRAS G12D mutation (>90% of PDAC have mutant KRAS) modulates the expression of the cytokines IL-10 and TGFβ by tumor cells, and both convert and accumulate naïve CD4+ T cells into Tregs, which can be reversed by inhibiting the RAF-MEK-ERK pathway [83].