As the TTT- RUVBL1/2 complex is required for the functional assembly of mTOR and activation 27, the observation that HPCAL1 deficiency in HCC cells and tumors as well facilitates the binding of RUVBL1 to TEL2 and TTI1, two essential components of TTT complex, solidifies that HPCAL1 is indeed implicated in the TTT-RUVBL1/2 complex formation. This evidence concerns the gene HPCAL1 and hepatocellular carcinoma.