PLK1 and cholangiocarcinoma: While PLK1 inhibitors such as BI2536 and GW843682X have been predicted to be effective drugs for CCA patients with a poor prognosis [59], PLK1 inhibitors such as NMS-1286937 (onvansertib) and BI2536, BI6727 (volasertib) have been evaluated in clinical trials and are generally well-tolerated, and their clinical efficacy is partially responsive with a monotherapy, particularly in cancers at advanced stages [60].