H19 promotes the migration and invasion of colon cancer by sponging miR-138 to upregulate the expression of HMGA1

Colon cancer is the most common digestive system malignancy, along with high mortality rate, familial transmissibility and hepatic metastasis. Our study investigated the role of long non-coding RNA H19 in colon cancer. We found that H19 was overexpressed in colon cancer tissues and cell lines, the interference of H19 by short hairpin RNA (shRNA) effectively decreased the migration and invasion of colon cancer cells (HT-29 and RKO). Besides, miR-138 was predicted a target of H19, and low expression of miR-138 was found in colon cancer tissues and cells. The silence of H19 strongly increased the expression of miR-138. The decreased level of miR-138 was elevated adding miR-138 mimic in RKO cells transfected with lncRNA-H19. Similarly, the upregulated level of miR-138 was downregulated adding miR-138 inhibitor in RKO cells transfected with H19 shRNA. The luciferase reporter confirmed the targeting reaction between H19 and miR-138. Moreover, the high-mobility group A (HMGA1) protein was predicted as a target of miR-138. HMGA1 was suppressed by H19 shRNA and could be up-regulated by miR-138 inhibitor. The migration and invasion ability of colon cancer was restrained by H19 shRNA and promoted by miR-138 inhibitor. Finally, the in vivo experiment revealed that H19 shRNA strongly reduced the tumor growth and tumor volume. H19 shRNA also inhibited metastasis via suppressing hepatic metastases and the expression of metastasis-related proteins. Taken together, our research indicated an H19-miR138-HMGA1 pathway in regulating the migration and invasion of colon cancer, providing new insight for treatment of colon cancer.