SMAD7 and hepatocellular carcinoma: For instance, our previous study showed that miR-92b could promote cell proliferation and metastasis of HCC by suppressing the expression of tumor-suppressor gene Smad7.4 Another study reported that miR-28-5p directly targeted IL-34 and had important roles in HCC growth and metastasis.5 Although many miRNAs were indicated to be related with pathogenesis of HCC, the roles of the majority of miRNAs in HCC remain to be explored.