Objective:To study the effects of fludarabine on growth of multiple myeloma KM3 cells and the influence of fludarabine on autocrining level of cytokines.Method:The effects of different concentrations of fludarabine on the proliferation of KM3 multiple myeloma cells were examined by MTT assay. The apoptosis of KM3 cells was stained with AnnexinⅤ/PI and detected by flow cytometr. The levels of IL-6 and sIL-6R autosecreted by KM3 cells were tested by ELISA after KM3 cells were treated with fludarabine. Result:Fludarabine inhibited the proliferation of KM3 cells and the inhibition effect were dependent on time and concentration.The MTT assay showed that the IC50 was 95 nmol/L with fludarabine treatment for 72 hours. The apoptosis rate of KM3 cells increased with fludarabine treatment at a dosage within 25~400 nmol/L. Fludarabine decreased the autocrining level of IL-6 slightly,and inhibited the level of VEGF and sIL-6R obviously. Conclusion:The proliferation of KM3 cells was markedly inhibited by fludarabine in a dose-dependent and time-dependent manner. Fludarabine can also decrease the level of VEGF,IL-6 and sIL-6R autocrined by KM3 cells.

Objective:To investigate the effect of fludarabine on interleukin-6 (IL-6) secreted by multiple myeloma KM3 cells.Methods:The effects of fludarabine on the proliferation of multiple myeloma KM3 cells were examined by MTT assay and flow cytometry. The levels of IL-6 and soluble interleukin-6 receptor (sIL-6R) in the supernatant after incubation with different concentrations of fludarabine were tested by enzyme-linked immunosorbant assay (ELISA). Results:Both MTT assay and flow cytometry showed that fludarabine had significant inhibitory effects on the growth of KM3 cells in vitro. Treatment with fludarabine 25, 50, 100, 200, 400 nmol/L for 72 h inhibited KM3 cells proliferation in concentration-dependent manner compared with control (P0.01). Fludarabine 400 nmol/L inhibited KM3 cells proliferation in a time-dependent manner. ELISA revealed that the level of IL-6 increased first and then significantly decreased after KM3 cells were incubated with fludarabine for 96 h and the level of sIL-6R decreased gradually coupled with the increase in the concentration of fludarabine. Conclusion:Fludarabine significantly inhibites the proliferation of KM3 cells and simultaneously decreases the autocrine of IL-6 and sIL-6R by KM3 cells.