ABSTRACT
OBJECTIVE: To investigate the mechanism of midostaurin derivative 5'''-methoxyfradcarbazole A of action in inhibiting mouse leukemia cells (CB3) growth. METHODS: MTT assay was employed to evaluate the effect of compound 5'''-methoxyfradcarbazole A on the proliferation of CB3 cells, and generate the growth inhibition curves. Flow cytometry and Annexin V-FITC /PI double staining were used to determine the changes of the cell cycle, cell differentiation and apoptosis. Western blot analysis was applied to test the effects of 5'''-methoxyfradcarbazole A on cyclin and apoptosis-related proteins. RESULTS: The compound 5'''-methoxyfradcarbazole A could significantly inhibit the growth of CB3 cells, and the half maximal inhibitory concentration (IC50) of the compound was (0.587±0.135)μmol•L-1. 5'''-Methoxyfradcarbazole A was able to induce early apoptosis and late apoptosis of CB3 cells in a time- and dose-dependent manner. At the same time, it also affected the cell cycle of CB3 and significantly increased the proportion of G2 phase. The expression of CD41, a platelet differentiation marker, and Ter119, an erythrocyte differentiation marker, were also increased in CB3 cells treated with 5'''-methoxyfradcarbazole A. Besides, the expressions of apoptosis-related proteins Bim, PARP1 and cyclin-related protein P21 were significantly increased, and the phosphorylated ERK protein was decreased. CONCLUSION: Midostaurin derivative 5'''-methoxyfradcarbazole A could increase the apoptosis of CB3 cells by promoting the expression of apoptotic protein Bim, and cause G2 phase arrest by increasing the expression of cyclin protein P21. Also, the changes of the expression levels of PARP1 and phosphorylated ERK protein also partly explain the inhibition of 5'''-methoxyfradcarbazole A on CB3 cells growth.
ABSTRACT
Midostaurin is an orally administered inhibitor of multiple tyrosine kinase receptors developed by Novartis Pharmaceuti-cals. In May 2017,it was approved in the USA for the treatment of adult patients with newly diagnosed FMS-like tyrosine kinase 3 (FLT3) mutation-positive acute myeloid leukaemia (AML). Its pharmacokinetics,pharmacodynamics,clinical trials,adverse effects and drug interactions were introduced in the paper.