不同浓度桦木酸对人胃癌MGC-803细胞自噬的影响

目的: 本研究利用不同浓度桦木酸处理人胃癌MGC-803细胞,以探究其对细胞自噬的影响。方法: 将人胃癌MGC-803细胞分为4组,每组3个复孔,对照组不加桦木酸处理,其余三组分别加入终浓度为10、20、30 mg/L桦木酸。桦木酸处理细胞48 h后,qRT-PCR检测桦木酸对人胃癌MGC-803细胞自噬相关基因mRNA表达的影响。Western blot检测药物处理细胞自噬相关基因的蛋白表达。利用免疫荧光检测药物处理后MGC-803细胞内LC3蛋白的胞内定位及表达。结果: 与对照组相比,在10～30 mg/L浓度范围内,桦木酸处理的人胃癌MGC-803细胞LC3、Beclin-1 mRNA的表达明显升高(P＜0.05),Beclin-1、LC3-Ⅱ蛋白的表达显著升高(P＜0.05),LC3-Ⅰ蛋白的表达明显降低(P＜0.05),其中30 mg/L处理组表现最佳。此外,桦木酸还可诱导MGC-803细胞LC3蛋白在细胞质内形成点状聚集。结论: 在10～30 mg/L浓度范围内,桦木酸能诱导人胃癌MGC-803细胞发生自噬。

Effects of betulinic acid at different concentrations on autophagy of human gastric cancer MGC-803 cells

Objective: In this study, human gastric cancer MGC-803 cells were treated with betulinic acid at different concentrations to investigate its effect on cell autophagy. Methods: The human gastric cancer MGC-803 cells were divided into 4 groups, each group was set with 3 replicate. The control group was not treated with betulinic acid, the other three groups were added with final concentration of 10,20,30 mg/L betulinic acid, respectively. Cells were treated with betulinic acid for 48 h,qRT-PCR was applied to detect the effect of betulinic acid on mRNA expressions of autophagy-related genes in human gastric cancer MGC-803 cells. Western blot was performed to determine the protein expressions of cell autophagy-related genes after drug treatment. Immunofluorescence was used to detect the localization and expression of LC3 protein in MGC-803 cells after drug treatment. Results: Compared with the control group,in the concentration range of 10~30 mg/L, the mRNA expression of LC3 and Beclin-1 in human gastric cancer MGC-803 cells treated with betulinic acid were increased significantly, the expressions of Beclin-1 and LC3-Ⅱ protein were also increased significantly, while the expression of LC3-Ⅰ protein was decreased significantly. Among them, betulinic acid at the concentration of 30 mg/L showed the best effects. In addition, betulinic acid induced the LC3 protein in MGC-803 cells to form spot aggregates in the cytoplasm. Conclusion: At the concentrations of 10~30 mg/L, betulinic acid can induce autophagy in human gastric cancer MGC-803 cells.