姜黄素对结肠癌细胞增殖抑制和凋亡诱导的作用研究

Effects of Curcumin on Proliferation and Apoptosis of Colorectal Carcinoma LoVo Cells

本文研究了姜黄素对结肠癌LoVo细胞的增殖抑制和凋亡诱导作用。不同浓度姜黄素作用体外培养的人结肠癌LoVo细胞后,倒置显微镜观察LoVo细胞的形态学变化,采用MTT法检测姜黄素对LoVo细胞的增殖抑制能力;RT-PCR技术检测Bax、Bcl-2和Caspase-3的mRNA表达水平;Annexin V-FITC/PI标记检测细胞凋亡率;Western blotting和免疫荧光细胞化学染色检测姜黄素作用前后c-myc蛋白表达的差异。结果表明,姜黄素可显著抑制人结肠癌LoVo细胞的増殖,具有明显的量效和时间依赖性,24、48和72 h姜黄素抑制LoVo细胞的IC50分别为(26.45±0.41)、(19.13±0.09)和(10.12±0.04)μmol/L;姜黄素可激活细胞中Bax和Caspase-3的mRNA表达,抑制Bcl-2的mRNA和c-myc蛋白的表达,姜黄素可诱导LoVo细胞发生凋亡。姜黄素通过上调Bax和Caspase-3表达,下调Bcl-2和c-myc的表达来抑制人结肠癌LoVo细胞的增殖并促使其凋亡。

To study the biological function and regulation mechanism of curcumin on proliferation and apoptosis of colorectal carcinoma cells LoVo, the LoVo cells were cultured and treated by curcumin in different concentrations in vitro. Effect of Curcumin on cell proliferation level was examined by MTT colorimetry method. The morphological changes of curcumin-treated LoVo cells were observed under inverted microscope. The mRNA levels of Bax, Bcl-2 and Caspase-3 were tested by RT-PCR. The cell apoptosis rate was detected by Annexin V-FITC/PI double staining. Western blotting and immunofluorescence staining were used to detect the different expressions of c-myc protein of LoVo cells before and after curcumin treatment. MTT test indicated curcumin could inhibit the growth and proliferation of LoVo cells in a time- and concentration-dependent manner. The inhibitory concentration 50% （IC50） of curcumin were 26.45±0.41 μmol/L, 19.13±0.09μmol/L and 10.12±04 μmol/L in LoVo cells at 24, 48 and 72 h, respectively. Flow cytometry instrument analysis showed that curcumin induced apoptosis of LoVo cells. Cureumin activated the expression of Bax and Caspase-3 genes, while inhibited the expression of Bcl-2 gene and c-myc protein. Curcumin significantly inhibited the proliferation and induced the apoptosis of human colorectal carcinoma cells LoVo. Such biological effect may be associated with activating Caspase-3 signal channel by activating Bax expression and inhibiting Bcl-2 and c-myc expression.