CPT2 and neoplasm: Thus, the downregulation of carnitine shuttle regulatory enzymes such as CPT1 has been linked to the occurrence of HCC and metastasizing progression [62,63]. Additionally, the expression changes appeared to be related to the tumor size, histological grade, intrahepatic metastasis, and tumor-node-metastasis stage, which are risk indicators for the prognosis of HCC patients [64].