TAGLN suppresses proliferation and invasion, and induces apoptosis of colorectal carcinoma cells.

In order to find the correlation between transgelin gene (TAGLN) and colorectal carcinoma occurrence, we investigated the expression of TAGLN in colorectal carcinoma tissue samples and colorectal carcinoma LoVo cells. Meanwhile, the effects of TAGLN on the characteristics of LoVo cells were also examined. The expressions of TAGLN in colorectal carcinoma tissues, adjacent normal tissues, and LoVo cells were detected by the Western blot method. The recombinant plasmid pcDNA3.1-TAGLN was established and transfected into LoVo cells with the help of Lipofectamine™ 2000. At the same time, the TAGLN siRNA was transfected into LoVo cells in another group. Forty-eight hours later, the expressions of TAGLN in all groups were assayed by Western blot, and the cell viability was analyzed by MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay. The cell cycle and cell apoptosis were examined by flow cytometry, and the cell invasive ability was analyzed by Transwell invasion experiment. The effect of TALGN on the expression of matrix metalloproteinase 9 (MMP9) was detected by Western blot. Western blot analysis showed that the expressions of TALGN in colorectal carcinoma tissues and LoVo cells were significantly decreased compared with colorectal carcinoma adjacent normal tissues (p < 0.01). In the overexpression or RNAi experiments, the plasmid pcDNA3.1-TAGLN significantly enhanced TALGN expression (p < 0.01), and TAGLN siRNA significantly decreased TAGLN expression (p < 0.01) in LoVo cells 48 h after transfection. In addition, MTT assay indicated that the cell viability of LoVo cells in the pcDNA3.1-TAGLN transfection group was significantly lower than that in the untransfected control group (p < 0.05). Furthermore, the overexpression of TAGLN significantly lowered the cell proliferation index (p < 0.05) and improved cell apoptosis (p < 0.01) in LoVo cells. In Transwell invasive experiments, the cell number, which had migrated through the chamber membrane, significantly decreased in the pcDNA3.1-TAGLN transfection group (p < 0.05) and significantly increased in the TAGLN knockdown group (p < 0.05) compared to the untransfected control group. At the same time, the expression of MMP9 was notably inhibited in the pcDNA3.1-TAGLN transfection group (p < 0.01). The expressions of TAGLN were inhibited in colorectal carcinoma tissues and colorectal carcinoma LoVo cells. The study also demonstrated that TAGLN could attenuate the proliferation and invasive ability of LoVo cells and enhance LoVo cell apoptosis. Furthermore, the expression of MMP9 was also inhibited by TAGLN. All these results could bring us a new perspective for biological therapy in colorectal carcinoma.