Effect of DLC-1 gene expression on matrix metalloproteinases secretion in high metastassis cell line HCCLM3

Objective: To construct the recombiant expression plasmid of DLC-1, observe the changes of matrix metalloproteinases after HCC cells being transfected, and to futher study the effect of DLC-1 on HCC cell invasiveness and metastasis in vitro. Methods: The effect of DLC-1 overexpression on HCC cell invasiveness and metastasis was studied in vitro, and a recombinant expression plasmid vector of pcDNA3. 1(-)-DLC-1 was constructed and then transfected into high metastasis HCCLM3 cell lines. Then MMP-2 and MMP-9 proteins were detected by ABC-ELISA and the gelatin zymogram assay. Results: The quantitative analysis showed that MMP-2 and MMP-9 in serum free culture media by ABC-ELISA were (46.887 ± 2.03) and (34.683 ± 1.98) ng/mL HCCLM3/pcDNA3.1 (-)-DLC 1), (47.172 ± 2.12) and (34.468 ± 2.54) ng/mL [HC-CLM3/pcDNA3.1(-)], (35-528 ± 2.89) and (31-542 ± 2.38) ng/mL (HCCLM3), respectively. The dramatical decrease in MMP-2 of these samples was found in the experiment. In the gelatin zymogram assay, MMP-2 band in culture media of HCCLM3 transfected with DLC-1 showed a lower density than the control, which was as the same as that in the MMP-2 quantitative assay. Conclusion: The high expression of DLC-1 can decrease MMPs secretion, which implied DLC-1 may play an important role in HCC cell invasion and metastasis, perhaps is one of relative metastasis-suppressors of HCC.