Mechanism of Stemona tuberosa Alkaloids in Inhibiting Proliferation and Inducing Apoptosis of Non-small Cell Lung Cancer NCI-H460 Cells / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo study the effect and underlying mechanism of Stemona tuberosa alkaloids on the proliferation and apoptosis of human non-small cell lung cancer NCI-H460 cells. MethodNon-small cell lung cancer NCI-H460 cells were divided into a blank group and S. tuberosa alkaloids groups （50， 100， 150， 200， and 250 mg·L-1）. The effect of S. tuberosa alkaloids on the proliferation of human NCI-H460 cells was observed by thiazolyl blue tetrazolium bromide （MTT） assay and colony formation assay. Cell apoptosis was observed by Hoechst 33258 staining and flow cytometry. Real-time fluorescence-based polymerase chain reaction （Real-time PCR） was used to detect the effect of S. tuberosa alkaloids on the mRNA expression of cysteinyl aspartate-specific protease 3 （Caspase-3）， B-cell lymphoma-2 （Bcl-2）， Bcl-2-associated X protein （Bax）， and epidermal growth factor receptor （EGFR）. The protein expression levels of Caspase-3， Bax， Bcl-2， protein kinase B （Akt）， phosphorylated （p-）Akt， EGFR， c-Jun N-terminal kinase （JNK）， p-JNK， p38 mitogen-activated protein kinase （p38 MAPK）， and p-p38 MAPK were measured by Western blot. ResultCompared with the blank group， the S. tuberosa alkaloids groups showed increased inhibition rate on cell proliferation （P<0.01）， reduced number of cell clones formed and the rate of cell clonal formation （P<0.05， P<0.01）， and increased karyopyknosis， cytoplasmic aggregation， and cell apoptosis rate （P<0.01）. The S. tuberosa alkaloids groups at 100， 150， 200， and 250 mg·L-1 showed increased Caspase-3 mRNA expression （P<0.05）， decreased EGFR mRNA expression （P<0.05， P<0.01）， up-regulated protein expression of Caspase-3 and p-JNK （P<0.01）， and down-regulated protein expression of EGFR and p-Akt （P<0.05， P<0.01）. Additionally， compared with the blank group， the S. tuberosa alkaloids groups showed increased expression of Bax mRNA （P<0.01）， decreased expression of Bcl-2 mRNA （P<0.01）， up-regulated protein expression of Bax and p-p38 MAPK （P<0.01）， and down-regulated protein expression of Bcl-2 （P<0.01）. ConclusionsS. tuberosa alkaloids can inhibit proliferation and induce apoptosis of human non-small cell lung cancer NCI-H460 cells， and the mechanism may be related to the inhibition of EGFR protein expression and phosphorylation of Akt protein， as well as the activation of the JNK/p38 MAPK signaling pathway.