OBJECTIVE: To investigate the effects of lentivirus mediated siRNA targeting human metastasis suppressor 1 (MTSS1, MIM-B gene) gene on the invasive and metastatic potentials of hepatocellular carcinoma (HCC) MHCC97H cells. METHODS: The siRNA targeting MTSS1 was cloned into one lentivirus work vector. The work vector and three package plasmids were co-transfected into 293T cells with the help of lipefeetamine 2000. Lentivirus was collected in 72 hours and was added to the cultured MHCC97H cells. The total cell MIM-B mRNA and MIM-B protein were extracted and underwent real-time PCR and western-blot test respectively. Boden chamber assay was used to evaluate the invasive potential of MHCC97H cells. Gelatin zymography was used to detect matrix metalloproteinase-2 (MMP2) activity. Metastatic human HCC nude mice models were established by orthotopic implantation with a high metastatic potential human HCC cell line MHCC97H. Twenty-four nude mice bearing orthotopic xenografts were randomized into black control group, Lenti-GFP group and intervention group (Lenti-MTSS1 group) 14 days after orthotopic implantation (8 per group). The ultrasound-guided multi-point injection was performed on mice with borate buffered saline, Lenti-GFP and Lenti-MTSS1 respectively. Mice were sacrificed on day 35 for the examination of pulmonary metastasis. The SPSS 13.0 soft ware was applied to data analysis. RESULTS: The small interfering RNA targeting MTSS1 was constructed successfully with a transfection efficiency of 97.0%, which produced a marked inhibition of invasive ability of MHCC97H cells through Matrigel, being 37.9+/-4.4, 37.4+/-5.3 and 26.6+/-4.6 in the black control group, Lenti-GFP group and Lenti-MTSS1 group (F = 26.695, P value is less than 0.01), respectively. MIM-B expression and MMP2 activity of intervention group were also significantly down-regulated as compared to the control group. The results of in vivo studies showed that the numbers of lung metastatic nodules were 6.5+/-2.6, 6.4+/-2.7 and 3.8+/-1.3 in the black control group, Lenti-GFP group and intervention group respectively with significant statistical difference (F = 3.637, P value is less than 0.05), accorded with tumor tissue MIM-B mRNA expression of 0.39+/-0.19, 0.38+/-0.10 and 0.16+/-0.11 respectively (F = 11.644, P value is less than 0.01) when comparison was made between control group and therapy group. CONCLUSION: Small interfering RNA mediated by lentivirus inhibited MIM-B expression and resulted in inhibition of the invasive and metastatic potentials of MHCC97H cells, which may attributed, in part, the down regulation of MMP2 activity, and thus may provide a new molecular targeted therapy for HCC patients in the future.
OBJECTIVE: To investigate the effects of lentivirus mediated siRNA targeting humanmetastasis suppressor 1 (MTSS1, MIM-B gene) gene on the invasive and metastatic potentials of hepatocellular carcinoma (HCC) MHCC97H cells. METHODS: The siRNA targeting MTSS1 was cloned into one lentivirus work vector. The work vector and three package plasmids were co-transfected into 293T cells with the help of lipefeetamine 2000. Lentivirus was collected in 72 hours and was added to the cultured MHCC97H cells. The total cell MIM-B mRNA and MIM-B protein were extracted and underwent real-time PCR and western-blot test respectively. Boden chamber assay was used to evaluate the invasive potential of MHCC97H cells. Gelatin zymography was used to detect matrix metalloproteinase-2 (MMP2) activity. Metastatic human HCC nude mice models were established by orthotopic implantation with a high metastatic potential human HCC cell line MHCC97H. Twenty-four nude mice bearing orthotopic xenografts were randomized into black control group, Lenti-GFP group and intervention group (Lenti-MTSS1 group) 14 days after orthotopic implantation (8 per group). The ultrasound-guided multi-point injection was performed on mice with borate buffered saline, Lenti-GFP and Lenti-MTSS1 respectively. Mice were sacrificed on day 35 for the examination of pulmonary metastasis. The SPSS 13.0 soft ware was applied to data analysis. RESULTS: The small interfering RNA targeting MTSS1 was constructed successfully with a transfection efficiency of 97.0%, which produced a marked inhibition of invasive ability of MHCC97H cells through Matrigel, being 37.9+/-4.4, 37.4+/-5.3 and 26.6+/-4.6 in the black control group, Lenti-GFP group and Lenti-MTSS1 group (F = 26.695, P value is less than 0.01), respectively. MIM-B expression and MMP2 activity of intervention group were also significantly down-regulated as compared to the control group. The results of in vivo studies showed that the numbers of lung metastatic nodules were 6.5+/-2.6, 6.4+/-2.7 and 3.8+/-1.3 in the black control group, Lenti-GFP group and intervention group respectively with significant statistical difference (F = 3.637, P value is less than 0.05), accorded with tumor tissue MIM-B mRNA expression of 0.39+/-0.19, 0.38+/-0.10 and 0.16+/-0.11 respectively (F = 11.644, P value is less than 0.01) when comparison was made between control group and therapy group. CONCLUSION: Small interfering RNA mediated by lentivirus inhibited MIM-B expression and resulted in inhibition of the invasive and metastatic potentials of MHCC97H cells, which may attributed, in part, the down regulation of MMP2 activity, and thus may provide a new molecular targeted therapy for HCC patients in the future.