Changing of TSG101 expression on the invasion and metastasis of gastric cancer cells

Objective To explore the functions of tumor susceptibility gene 101 (TSG101) in the invasion and metastasis of gastric cancer cells by cell culture. Methods The TSG101 eukaryotic expression and empty plasmids were transfected into gastric cancer cell line SGC7901.After screening with G418,single cell clone was selected and cultured.The expression of TSG101 was detected by reverse transcription (RT)-PCR and Western blotting.Cells were divided into TSG101 eukaryotic expression plasmid and blank control groups.Then the relationship was examined between TSG101 expression and tumor invasion and metastasis through the invasion, mobile, adhesion and damage scart experiment. Results The expression levels of TSG101 in mRNA and protein in the TSG101 eukaryotic expression group were significantly higher than those of the plasmid and blank control groups (0.85±0.09 vs 0.55±0.07,0.45±0.07 and 29.4±1.2 vs 17.0±0.4,15.9±0.4,all P<0.05).The cell number of TSG101 eukaryotic expression group through Matrigel, laminin, type Ⅳ collagen protein (84±14, 128±10, 62±7) were significantly higher than those of the plasmid group (55±9,77±10,31±6) and blank control group (48±8,76±9, 24±5,all P<0.01).The number of cells adhereent to Matrigel, laminin, type Ⅳ collagen protein of the TSG101 eukaryotic expression group (0.97±0.04, 1.34±0.04, 0.90±0.01) were obviously higher than thoses of the plasmid group (0.53±0.03, 0.75±0.05,0.42±0.02) and blank control group (0.60±0.03,0.72±0.03,0.40±0.01,all P<0.01).The number of TSG101 eukaryotic expression group cell migrating to membrane lower surface was obviously higher than that of the plasmid group and blank control group (87±13 vs 54±8,48±7, all P<0.01).The fusion speed of the TSG101 eukaryotic expression group was faster than that of plasmid and blank control groups after cultivating for 24 and 48 h. Conclusions TSG101 expression increases significantly in SGC-7901 cells after a stable transfection of TSG101 eukaryotic expression plasmids.Also the capacities of invasion and metastasis become markedly enhanced. Key words: Stomach neoplasms; Transfection; Neoplasm invasiveness; TSG101