RAF1 and hepatocellular carcinoma: Here, we have shown for the first time that melatonin induces the expression of the miRNA let7i-3p in HCC cell lines and have further demonstrated that let7i-3p directly inhibits RAF1 protein translation and activation of the RAF1 downstream oncogenic pathway, thereby suppressing the ability of HCC cells to grow and metastasize and promoting their apoptosis (Figure 7E).