Effect of Koumine on Proliferation and Apoptosis of Colorectal Cancer Cells via ROS/JNK/FoxO3a Signaling Pathway / 中国实验方剂学杂志

ABSTRACT

Objective:To explore the effect and underlying mechanism of koumine （Kou） at different concentrations （0， 100， 200， 400 μmol·L^-1） on the proliferation and apoptosis of colorectal cancer HCT-116 cells. Method:After 24 hours of<italic> in vitro</italic> intervention with HCT-116 cells by Kou， cell counting kit-8 （CCK-8） assay was used to detect its effect on cell proliferation. Flow cytometry was used to detect cell cycle， apoptosis， and reactive oxygen species （ROS） expression. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression of forkhead box O3a （FoxO3a）. Cells were transfected with small interfering ribonucleic acid （siRNA）. Western blot was employed to detect the protein expression of the FoxO3a target gene. Result:Compared with the conditions in the blank group， Kou treatment reduced the proliferation rate of HCT-116 cells （<italic>P</italic><0.05， <italic>P</italic><0.01） in a dose-dependent manner， caused cell cycle arrest in the G₀/G₁ phase， and induced the apoptosis of HCT-116 cells （<italic>P</italic><0.05， <italic>P</italic><0.01）， which was positively correlated with the concentration of Kou. FoxO3a siRNA interference reduced the expression of FoxO3a and its downstream target genes cyclin-dependent kinase inhibitor 1A （p21）， cyclin-dependent kinase inhibitor 1B （p27）， and Bcl-2 interacting mediator of cell death （Bim） （<italic>P</italic><0.01）. Kou treatment induced the activation of c-Jun <italic>N</italic>-terminal kinase （JNK） in HCT116 cells. SP600125 （JNK specific inhibitor） treatment inhibited the Kou-induced FoxO3a activation and the expression of its downstream target genes. <italic>N</italic>-acetyl cysteine （NAC） treatment reduced Kou-induced ROS levels （<italic>P</italic><0.01） and JNK signal activation. The above results were significantly different from those in the blank group （<italic>P</italic><0.01）. Conclusion:Kou can effectively inhibit the proliferation of HCT-116 cells and promote apoptosis， and the mechanism may be related to the regulation of the ROS/JNK/FoxO3a pathway.