Conversely, overexpression of HCG18 markedly inhibited miR-30a-5p expression in HCC cells, but no significant alteration in miR-30a-5p expression upon transfected with HCG18-MT (Fig. 6d), which confirms that HCG18 competitively regulates miR-30a-5p expression. This evidence concerns the gene MCAT and hepatocellular carcinoma.