Abstract: Objective To investigate the effect of tanshinone Ⅱ A on proliferation, invasionand migration of colon cancer SW480 cells by targeting miR-143 via metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) . Methods SW480 cells were treated with 0, 10, 20, and40 μmol / L of tanshinone Ⅱ A, and were randomly divided into 4 groups: Control group, tanshinone Ⅱ A low-, medium-, and high-dose groups. CCK8 assay was used to detect cellproliferation. Wound-healing and Transwell assay were used to detect the number of migrated and invaded cells. The expression levels of MALAT1 and miR-143 mRNA were detected by RT-PCR. Theluciferase gene reporter assay was used to verify the targeting relationship between MALAT1 andmiR-143. SW480 cells treated with tanshinone Ⅱ A (40 μmol / L) were transfected with pcDNA MALAT1 and miR-143 mimic separately or combined, and were randomly divided into 5 groups:Control group, PCDNA 3. 1 group, pcDNA-MALAT1 group, MALAT1 + mimic NC group, and MALAT1 + miR-143 mimic group. The proliferation, invasion, and migration of cells in the abovegroups were detected. Results Compared with those in the Control group, the cell proliferation,number of invaded cells, wound-healing rate, and MALAT1 mRNA expression level in the tanshinone Ⅱ A medium-dose and high-dose groups were significantly decreased ( P < 0. 05), and the miR-143 mRNA expression level was significantly increased (P< 0. 05) . MALAT1 has a targetingrelationship with miR-143. Compared with those in the pcDNA-MALAT1 group, the cell proliferation, number of invaded cells, and wound-healing rate in the MALAT1 + miR-143 mimic groupwere significantly decreased (P< 0. 05) . Conclusion Tanshinone Ⅱ A exerts its anti-colon cancer effect through theMALAT1 / miR-143 axis.

Key words: