The results showed that, compared with FHC cells, the expression of miR-let-7 mRNA in colon cancer cell HCT116 was reduced, and the expression of HMGA2 mRNA and protein was increased (P < 0.05, Figures 1(a)–1(c)) It is suggested that the expression of miR-let-7 is downregulated and the expression of HMGA2 is upregulated in colon cancer cell HCT116. The gene discussed is HMGA2; the disease is malignant colon neoplasm.