U0126 enhances sorafenib-induced proliferation inhibition,apoptosis and differentiation in K562 cells

AIM: To observe the effects of sorafenib and sorafenib combined with an MEK kinase inhibitor U0126 on the proliferation,apoptosis and differentiation in human chronic myelogenous leukemia cell line K562.METHODS: K562 cells were treated with different concentrations of sorafenib and U0126 or 10 μmol/L U0126 combined with different concentrations of sorafenib for 48 h.Cell inhibitory rate was determined by CCK-8 assay.Apoptosis analysis was conducted by Hoechst 33342 and PI staining.Cell cycle analysis and benzidine staining were used to confirm K562 cells towards erythroid differentiation.The protein expression of c-Myc was detected by Western blotting.RESULTS: U0126 enhanced sorafenib-induced proliferation inhibition,apoptosis and differentiation in K562 cells.Sorafenib combined with U0126 remarkably reduced the protein level of c-Myc.CONCLUSION: U0126 synergistically enhances sorafenib-induced proliferation inhibition,apoptosis and differentiation in K562 cells through reducing c-Myc protein level.