Therefore, our studies suggested that PDGFRα and KIT downregulation in pancreatic cancer leads to decreased p70S6K phosphorylation at Ser 418, and increased IRS-1 phosphorylation at Ser 636 via increased PI3K/AKT mTOR/P70S6K signaling. This evidence concerns the gene RPS6KB1 and familial pancreatic carcinoma.