MTOR and cholangiocarcinoma: The most deregulated pathways based on Ov-CCA studies were PI3K (Phosphoinositide 3-kinase), AKT (protein kinase B), mTOR (mammalian target of rapamycin), PTEN (phosphatase and tensin homolog), CTNNB1 (Catenin Beta-1), NAKB1 (Nuclear Factor Kappa B Subunit 1), MAPK (Mitogen-Activated Protein Kinase), and RTK (Receptor Tyrosine Kinase).