In a study, Hu and his colleagues found that when CCA cells were treated with phenformin, autophagy-related genes ATG5, ATG7 and Beclin1 were up-regulated and cell death was increased, suggesting that phenformin can inhibit the growth of bile duct cancer cells by inducing autophagy in CCA cells [112]. The gene discussed is BECN1; the disease is cholangiocarcinoma.