ABSTRACT
The aim of this study was to investigate the apoptosis-inducing effect of gambogic acid (GA) on Jurkat cells and its underlying signaling pathway. Apoptosis induced by GA and some inhibitors was assayed by Annexin V/PI doubling staining. The levels of caspase 3, caspase 8 and caspase 9 activated in living Jurkat cells were measured by flow cytometry. The expressions of caspase 3, caspase 9, p-JNK and P38 were detected by Western blot. The results showed that GA induced apoptosis of Jurkat cells in a dose-dependent manner. The positive cell number of activated caspase 3, caspase 8, caspase 9 and the levels of activated caspase 3, caspase 9, p-JNK, P38 increased after Jurkat cells were treated with GA. ROS, CaMKII, caspase 3, caspase 9, MAPKK, JNK1/2 and P38 inhibitors had some significant effect on GA-induced apoptosis. ROS, CaMKII, MAPKK, JNK1/2 and P38 inhibitors decreased the levels of activated caspase 3, caspase 9 by GA.ROS, CaMKII, MAPKK, JNK1/2 inhibitors decreased the levels of p-JNK by GA. ROS, CaMKII, MAPKK, P38 inhibitors decreased the levels of P38 by GA. It is concluded that GA induced apoptosis of Jurkat cells by activated caspases through activating of ROS-CaMKII-MAPKK-JNK/P38 pathway.
Subject(s)
Humans , Apoptosis , Caspase 3 , Metabolism , Caspase 9 , Metabolism , JNK Mitogen-Activated Protein Kinases , Metabolism , Jurkat Cells , MAP Kinase Signaling System , Xanthones , Pharmacology , p38 Mitogen-Activated Protein Kinases , MetabolismABSTRACT
This study was aimed to investigate the apoptosis-inducing effect of gambogic acid (GA) on K562 cell line and its mechanism. The K562 cells were treated with GA at different concentrations and times, the inhibition rates were detected by MTT assay. Apoptosis induced by GA was assayed by Annexin-V/PI doubling staining. The influence of GA on cell cycle was studied by propidium iodide method. The mitochondrial membrane potential was measured by JC assay. The levels of caspase 3, caspase 8 and caspase 9 activated by fluorescein in living K562 cells were measured by caspGLOW(TM) fluorescein staining kit. The results showed that after incubation with GA, K562 cell proliferation was dramatically inhibited in concentration- and time-dependent manners. K562/A02 cells need higher GA concentration (> 2 microg/ml) to show antiproliferative effect, compared with that of K562 cells (> 0.5 microg/ml). Apoptosis could be induced by GA but the influence on cell cycle was not significant. GA could decrease the mitochondrial membrane potential and increase the activated caspase 3, caspase 8, caspase 9 positive cell levels by 2.19%, -1.95%, 34.01% in 24 hr and 60.4%, 71.3%, 77.7% in 48 hr respectively. It is concluded that the GA can significantly inhibit the proliferation of K562 cells without influence on cell cycles. The GA triggers K562 cell apoptosis through both intrinsic and extrinsic pathways.
Subject(s)
Humans , Apoptosis , Caspase 3 , Metabolism , Caspase 8 , Metabolism , Caspase 9 , Metabolism , Cell Cycle , Cell Proliferation , K562 Cells , Membrane Potential, Mitochondrial , Xanthones , PharmacologyABSTRACT
Granulocytic sarcoma of oral cavity is a kind of isolated tumor constructed by immature myeloid cells. Two cases of granulocytic sarcoma of oral cavity were analyzed. The literatures about granulocytic sarcoma were overviewed.