ABSTRACT
The objective of this study was to investigate the effect of the new generation of tyrosine kinase inhibitor flumatinib mesylate on C-MYC, HIF-1α and VEGF in multiple myeloma (MM) cell line U266. Different concentrations (1, 5, 10 µmol/L) of flumatinib mesylate were used to act on U266 cell line for 8, 16 and 24 h, and the expression of C-MYC, and HIF-1α genes was detected by real-time fluorescence-quantitative PCR, the expression of C-MYC, HIF-1α and VEGF was measured by Western blot. The results showed that the gene expression of C-MYC and HIF-1 genes decreased gradually with the increasing of flumatinib mesylate concentration (P < 0.05). At the same concentration of flumatinib mesylate, the expression of C-MYC and HIF-1α gene decreased gradually with prolonging of treatment time with the flumatinib mesylate (P < 0.05). When the flumatinib mesylate acted the U266 cell line for 16 h, the expression of C-MYC, HIF-1α and VEGF decreased gradually with the increasing of flumatinib mesylate concentration (P < 0.05). It is concluded that the flumatinib mesylate can reduce the expression of C-MYC, HIF-1 α and VEGF in U266 cell line in a time- and dose-dependent manners, so flumatinib mesylate may become a new drug for MM therapy.
Subject(s)
Humans , Aminopyridines , Pharmacology , Benzamides , Pharmacology , Cell Line, Tumor , Gene Expression Regulation, Leukemic , Genes, myc , Hypoxia-Inducible Factor 1, alpha Subunit , Metabolism , Vascular Endothelial Growth Factor A , MetabolismABSTRACT
This study was purposed to explore the effect of a new generation of histone deacetylase inhibitor LBH589 alone or combined with bortezomib (Bor) on multiple myeloma cells (MM1R) in vitro. The effect of LBH589 (10, 20, 50 nmol/L) alone or combined with Bor (10, 20 nmol/L) on MM1R proliferation was detected by MTT method; the effect of LBH589 on cell cycle and apoptosis of MM1R cells were determined by flow cytometry; the histone H4 acetylation level of MM1R cells treated with LBH589 (10, 20, 50 nmol/L) for 24 h was analyzed by Western blot. The results showed that the LBH589 alone or combined with Bor all could inhibit the proliferation of MM1R cells in a concentration- and time-dependent manner. After MM1R cells were treated with drugs for 48 h, the cells in G(0)/G(1) phase increased, the cells in G(2)/M and S phase decreased, suggesting the arrest of cells in G(0)/G(1) phase, at the same time, the apoptosis rate of MM1R cells treated with drugs increased in a concentration-dependent manner, while the effect of LBH589 combined with Bor was more obvious than that of LBH589 alone (P < 0.001). Western blot analysis showed that the histone H4 acetylation level was enhanced in concentration-dependent manner after MM1R cells were treated with different concentrations of LBH589 for 24 h. It is concluded that the LBH589 can inhibit the proliferation of MM1R cells, block the cell cycle, induce cell apoptosis, moreover LBH589 combined with Bor has synergistic effect on MM1R cells.
Subject(s)
Humans , Acetylation , Apoptosis , Boronic Acids , Pharmacology , Bortezomib , Cell Cycle , Cell Line, Tumor , Histone Deacetylase Inhibitors , Pharmacology , Hydroxamic Acids , Pharmacology , Indoles , Pharmacology , Multiple Myeloma , Pathology , Pyrazines , PharmacologyABSTRACT
The objective of this study was to investigate expression of interferon regulatory factors (ICSBP/IRF8) and the potential role of DNA methylation in silencing ICSBP/IRF8 gene in multiple myeloma (MM) cell line U266 and bone marrow mononuclear cells from 10 MM patients (MM-BMMNC). The bone marrow mononuclear cells from 10 healthy persons (N-BMMNC) were collected and used as normal controls. Expression of ICSBP/IRF8 gene was detected by real-time fluorescence quantitative PCR (using 2(-ΔΔCT) to calculate); DNA methylation level of the ICSBP/IRF8 gene was measured using methylation-specific PCR (using the ratio of interest gene ICSBP/IRF8 and internal reference β-actin expression as results). The results showed that as compared with N-BMMNC the lower expression of ICSBP/IRF8 gene was found in U266 cells and MM-BMMNC, the hypermethylation of the CpG island in the ICSBP/IRF8 promoter was observed, there were significant differences between N-BMMNC and MM-BMMNC or U266 cells (P < 0.05). It is concluded that the expression of ICSBP/IRF8 gene can be silenced in the MM-BMMNC and U226 cells. As the hypermethylation of CpG island in ICSBP/IRF8 promoter is a frequent event in MM cells, the ICSBP/IRF8 gene silencing caused by DNA methylation may take part in the pathogenesis and development of MM.