Objective To investigate whether the matrine induce autophagy in human breast cancer Bcap-37 cells by down-regulating PI3K/Akt signal pathway via inhibition of mTOR or not. Methods Human breast cancer Bcap-37 cells were cultured in vitro and treated by different final concentrations (0, 1, 2 mg/mL) of matrine ± chloroquine(autophagy inhibitor), then cultured for 24 h. Western-blot assay was used to detect the protein expres-sion level of mTOR, p-mTOR, p70S6K, p-p70S6, eIF4E, which were related to PI3K/Akt signaling pathway. The same cells were cultured in vitro and treated by matrine (0, 1, 2 mg/mL) ± bafilomycinA1 (autophagy inhibitor)/rapamcin (autophagy revulsant) for 24 h. Western-blot assay was used to detect the level of eIF4E. Results The expression of p-mTOR, p-p70S6k and eIF4E proteins down-regulated after Bcap-37 cells were treated with matrine at 0, 1, 2 mg/mL for 24 h in a does-dependent manner, but had no obvious changes after Bcap-37 cells were treated with matrine + chloroquine for the same while. The expression of eIF4E protein also had no obvious change after Bcap-37 cells were treated with matrine + bafilomycinA1 for 24 h, however the expression of eIF4E protein down-regulated after the cells were treated with matrine+ rapamcin in a does dependent manner. Conclu-sion The molecular mechanism of autophagy induced by the effect of matrine in human breast cancer Bcap-37 cells may be via down-regulating PI3K/Akt/mTOR signaling pathway.%目的：探讨苦参碱是否可通过抑制mTOR活性阻断PI3K/Akt信号通路，诱导人乳腺癌Bcap-37细胞自噬发生。方法苦参碱（终浓度为0、1、2mg/mL）±氯喹（chloroquine）（自噬抑制剂）处理乳腺癌Bcap-37细胞24h，运用免疫印迹（Western-blot）法检测PI3K/Akt信号通路自噬相关蛋白mTOR、p-mTOR、p70S6K、p-p70S6、eIF4E表达。苦参碱（终浓度为0、1、2mg/mL）±BafilomycinA1（自噬抑制剂）/Rapamcin（自噬诱导剂）处理乳腺癌Bcap-37细胞24h，Western-blot法检测eIF4E蛋白的表达。结果苦参碱剂量依赖性抑制mTOR、p70S6k磷酸化，同时降低eIF4E蛋白表达；当苦参碱联合氯喹（CQ）作用于乳腺癌Bcap-37细胞时，则对上述蛋白表达均无明显抑制作用。苦参碱联合BafilomycinA1作用于Bcap-37细胞时，eIF4E蛋白表达同样无明显改变；苦参碱联合Rapamcin时，eIF4E蛋白表达则呈剂量依赖性降低。结论苦参碱可通过抑制mTOR活性阻断PI3K/Akt信号通路，从而诱导人乳腺癌Bcap-37细胞自噬发生。
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