TFE3 and bile duct neoplasm: The regions showing neoplasm of the bile ducts showed nuclear TFEB, TFE3, and SOX9, and hyperactivation of mTORC1 as evidenced by immunostaining for the phosphorylated S6 protein of the 40S ribosomal subunit (P-S6), used as readout of mTORC1 activity [27, 29, 30] (Fig. 3F).