MT1X and hepatocellular carcinoma: With regard to the four MT1s we identified, studies have confirmed that the expression of MT1G could serve as tumor suppressor by inhibiting cell proliferation and enhancing apoptosis in HCC [25]; MT1F was proven to inhibit the HCC cell growth [26]; Liu et al. demonstrated that MT1X is probably a prognostic biomarker and reduces the progression and metastasis of HCC [27].