Further, β-catenin activation induced by CCR9 increased the expression of Cyclin E1, Cyclin D1, and E-Cadherin to increase the lethal dose of gemcitabine in pancreatic cancer, suggesting that CCR9/β-catenin signaling enhances pancreatic cancer chemoresistance [20]. Here, CCNE1 is linked to familial pancreatic carcinoma.