PPT1 and cholangiocarcinoma: After initial results suggesting antineoplastic activity against cholangiocarcinoma in vitro and in vivo in a murine model [134], the novel PPT1 inhibitor GNS561 is now evaluated in a clinical trial in combination with monalizumab, a checkpoint inhibitor, and avdoralimab, a CD88 blocker, in cancer patients (NCT04333914; Table 2), holding promise for others to follow.