Effects of MTA1 on biological behaviors of gastric cancer cells / 中华肿瘤杂志

ABSTRACT

Objective@#To study the effects of metastasis associated 1 (MTA1) on biological characteristics such as migration, invasion and proliferation of gastric cancer (GC) cells.@*Methods@#pSilencer3.1-MTA1-siRNA vector was used to establish human gastric cancer BGC-823 cell lines with constitutive MTA1-knockdown. Boyden, wound healing, clony forming assay and 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) assay were performed to identify the effects of MTA1-deficiency on the biological behaviors of BGC-823 cells in vitro. Simultaneously, MTA1 overexpressed BGC-823 cell line was established by pcDNA3-MTA1 plasmid transfection for reverse verification. In addition, the role of MTA1 in the tumorigenicity of gastric cancer BGC823 cells in vivo was examined by subcutaneous injection of BGC-823 cells expressing different MTA1 levels into nude mice. Reverse transcription-polymerase chain reaction (RT-PCR) and western blot were used to detect the expression levels of integrin β1, cyclin D1 and uPAR in pSilencer3.1-MTA1-siRNA, pcDNA3-MTA1 transfected cells and control cells.@*Results@#MTA1 knocked down or upregulated BGC-823 cell lines were successfully generated by transfecting pSilencer3.1-MTA1-siRNA or pcDNA3-MTA1 vector with lipofectamine 2000, respectively. The Boyden and wound healing experiments showed metastasis and invasion ability in MTA1 knocked down cells (25±2, 12±1) were significantly decreased when compared with those of control (78±2, 50±2) and MTA1-overexpressed groups (218±2, 269±3; P<0.05). The results of MTT assay and colony forming assay were significantly decreased when compared with those of showed that MTA1 overexpressed cells grew more rapidly and formed more colonies in vitro and induced worse malignant tumors in vivo, while MTA1 knocked down cells presented the reversed phenotype[control group (1 482.41±511.90) mm3, (1.39±0.29)g; MTA1 overexpressed group [(3 158.73±1 823.22) mm3, (2.23±0.51)g; MTA1-downregulated group (711.32±284.30)mm3, (0.87±0.21) g ; P<0.05)]. In addition, RT-PCR result showed that the expression level of MTA1 was positively correlated with the known metastasis-related genes (integrinβ1, cyclinD1, uPAR).@*Conclusions@#MTA1 promotes the invasion, migration and proliferation of human gastric cancer BGC-823 cells. On the contrary, down-regulation of MTA1 significantly inhibits tumorigenicity of BGC-823 cells and induces favorable phenotypes. MTA1 may promote the malignant phenotype of BGC-23 cells via regulating the expressions of integrinβ1, cyclinD1 and uPAR.