Objective To observe the anti-tumor effect on human multiple myeloma cell lines U266 and KM3 with a combination of varinostat and melphalan in vitro.Methods The cell proliferation of U266 and KM3 was datected with MTT assay when treated them with vorinostat alone and melphalan alone,then calculate their IC50 values respectively.Fixed the concentrations of vorinostator melphalan,the cell proliferation was datected in combination with melphalan/vorinostat in seriesly concentrations by MTr assay.Then to calculate drug combination index(CI).Results The IC50 value of U266 was 5.0-7.5 μmol/L and that of KM3 was 2.5-5.0 μmol/L when treated by vorinostat alone,the IC50 value of U266 was 40-60 μmol/L and that of KM3 was 60-80 μmol/L treated by melphalan alone.When fixed the concentration of vorinostat(in U266 the concentration was 1.25 μmol/L,in KM3 the concentration was 1.0 μ mol/L),Synergism(CI＜0.9)was observed when the concentrations of melphalan were 20 μmol/L,40 μmol/L,60 μ mol/L and 80 μ mol/L in U266,40 μmol/L,60 μmol/L,80 μmol/L and 100 μmol/L in KM3;When fixed the concertration of melphalan (in U266,was 10 μmol/L,in KM3 was 20 μmol/L),synergism(CI＜0.9)was observed when the concentrations of vorinostat were 1.0 μmol/L,2.5 μmol/L,5.0 μmol/L and 7.5 μmol/L in U266,and 1.0 μmol/L,2.5μmol/L,5.0 μmol/L in KM3.An additive effect was observed with the czombination of vorinostat 7.5 μmol/L plus melphalan 20 μmol/L in KM3(CI=0.93).Conclusion Vorinostat had potential anti-myeloma effect alone,and had synergistic anti-tumor effect with melphalan in vitro.

In order to explore the molecular mechanisms of sodium butyrate and trichostatin A on K562 cell proliferation/differentiation, K562 cells were grown in the absence or presence of sodium butyrate or trichostatin A. The percentage of viable cells was determined by trypan blue exclusion. Differentiation was determined by nitro-blue tetrazolium (NBT) reduction and cell surface adhesion molecules analyzed by FACS. Cell cycle distribution was studied after DNA staining by propidium iodide. Cell cycle regulatory proteins were detected by Western blot and reverse transcription-polymerase chain reaction. The results showed that sodium butyrate blocked cells mainly at the G0/G1 phase of the cell cycle, whereas trichostatin A arrested the cells at G2 phase. Sodium butyrate could down-regulate the mRNA expression of cyclin D1, but not affect its protein expression; down-regulate the protein expression of cyclin D3, but not affect its mRNA expression. Trichostatin A showed similar effects on cyclin D1 and D3 as sodium butyrate. Both sodium butyrate and trichostatin A could stimulate p21 expression of K562 cells at mRNA and protein levels. It may be concluded that sodium butyrate and trichostatin A could promote the proliferation/differentiation of the K562 cells, which might be contributed to the induced expression of cyclin D3 and p21 proteins.
Butyrates ; pharmacology ; Cell Cycle ; drug effects ; Cell Differentiation ; drug effects ; Cell Division ; drug effects ; Cyclin D ; Cyclin-Dependent Kinase Inhibitor p21 ; Cyclins ; biosynthesis ; genetics ; Gene Expression ; drug effects ; Histone Deacetylase Inhibitors ; Humans ; Hydroxamic Acids ; pharmacology ; K562 Cells

Objective:To evaluate the role of miR-124-3p in reduction of oxygen-glucose deprivation and restoration (OGD/R) injury by electrostimulation preconditioning in microglia and its relationship with microglial polarization.Methods:The well-growing BV2 cells were divided into 4 groups ( n=30 each) by the random number table method: control group (group C), OGD/R group, electrostimulation preconditioning group (group E) and miR-124-3p inhibitor group (group I). Group C was cultured under normal conditions, and group OGD/R was deprived of oxygen and glucose for 2 h followed by restoration of oxygen and glucose supply for 24 h to develop the OGD/R injury model. In group E, cells were stimulated with 100 mV/mm direct current for 4 h before oxygen-glucose deprivation, and the other treatments were similar to those previously described in group OGD/R. Group I was transfected with micrOFF? mmu-miR-124-3p inhibitor at 48 h before oxygen-glucose deprivation, and the other treatments were similar to those previously described in group E. The cell survival rate was determined by CCK-8 assay, the concentrations of tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β) and IL-10 in the cell supernatant were measured by enzyme-linked immunosorbent assay. The expression of a surface marker of M1 microglia inducible nitric oxide synthase (iNOS) and a surface marker of M2 microglia arginase 1 (Arg-1) was detected by immunofluorescence and Western blot, respectively. The expression of iNOS and Arg-1 mRNA and miR-124-3p was detected by quantitative polymerase chain reaction. Results:Compared with group C, the cell survival rate was significantly decreased, the concentrations of TNF-α, IL-1β and IL-10 in the supernatant were increased, and the expression of iNOS and Arg-1 protein and mRNA and miR-124-3p was up-regulated in the remaining three groups ( P<0.05). Compared with group OGD/R, the cell survival rate was significantly increased, the concentrations of TNF-α and IL-1β in the supernatant were decreased, the IL-10 concentration was increased, the expression of iNOS protein and mRNA was down-regulated, and the expression of Arg-1 protein and mRNA and miR-124-3p was up-regulated in E and I groups ( P<0.05). Compared with group E, the cell survival rate was significantly decreased, the concentrations of TNF-α and IL-1β in the supernatant were increased, the IL-10 concentration was decreased, the expression of iNOS protein and mRNA was up-regulated, and the expression of Arg-1 protein and mRNA and miR-124-3p was down-regulated in group I ( P<0.05). Conclusions:The mechanism by which electrostimulation preconditioning reduces OGD/R injury in microglia is related to up-regulation of the expression of miR-124-3p, promotion of M2 microglia polarization, inhibition of M1 microglia polarization, and thus inhibiting the inflammatory responses.