phytosterols and Leukemia--Myelogenous--Chronic--BCR-ABL-Positive

C-21 steroids displayed the activities of immunosuppressive, anti-inflammatory and anti-virus effects by the reports. However, its antitumor effects and molecular mechanism remain unclear. We previously isolated and identified a C-21 steroidal glycoside (BW18) from the root of Cynanchum atratum Bunge. This study was aimed to assess anti-leukemia activity and its underlying mechanism in K562 cells. MTT assay results showed that BW18 inhibited cell viability and proliferation of K562 cells. We also found that BW18 could induce S phase cell cycle arrest and apoptosis. Furthermore, our results demonstrated that BW18 regulated the expression of apoptosis and cell cycle related proteins. Mechanism investigation revealed that the anti-leukemia activity of BW18 may be mediated through MAPK pathway. These findings indicate that BW18 possesses an excellent anti-leukemia activity via regulating MAPK pathway leading to S phase cell cycle arrest and apoptosis, which suggested BW18 could be as a potential alternative therapeutic agent for CML patients.

Topics: Antineoplastic Agents; Apoptosis; Cell Cycle Checkpoints; Dose-Response Relationship, Drug; Drugs, Chinese Herbal; Glycosides; Humans; K562 Cells; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; MAP Kinase Signaling System; Phytosterols; S Phase