中电导钙激活性钾通道在人多发性骨髓瘤细胞增殖中的作用

Intermediate-conductance Ca^(2+)-activated K^+ channels are involved in regulating proliferation of multiple myeloma cells

目的探讨中电导钙激活性钾通道(intermediate-conductance Ca2+-activated K+channels,IKCa1)在人多发性骨髓瘤(multiple myeloma,MM)细胞增殖中的作用。方法通过台盼蓝拒染法检测IKCa1阻滞剂CLO对MM细胞株RPMI 8226和U266生存活力的影响,应用流式细胞仪检测CLO作用于RPMI 8226和U266细胞后细胞周期分布及细胞内钙离子浓度([Ca2+]i)变化。结果 CLO以浓度依赖方式显著抑制RPMI 8226和U266细胞生长,10μmol/L CLO作用48 h后,RPMI 8226细胞和U266细胞周期明显被阻滞于G0/G1期,S期显著减少。10μmol/L CLO作用1min后,RPMI 8226和U266细胞内Fluo-3/AM荧光强分别为(448.3±32.8)和(675.9±45.8),分别与对照组(56.5±7.2)和(31.8±4.5)相比具有显著差异(P<0.05)。结论钙激活性钾通道阻断剂克霉唑抑制MM细胞增殖,其机制可能与CLO通过调节细胞内钙水平引起细胞周期阻滞于G0/G1期有关。

Objective To study the role of the intermediate-conductance Ca2＋ -activated K＋ （IKCal） channels in the proliferation of multiple myeloma （MM） cells. Methods Trypan Blue exclusion was used to evaluate the impact of clotrimazole （ an inhibitor of the KCal ） on the ability of survival rates of PRMI 8226 and U266 cells of MM cell lines, and flow eytometry was used to analyze the cell distribution in cell cycle, and to examine the change of the [ Ca2＋ ] i of these two cell lines. Results CLO caused a dose-dependent decrease in cell number of MM cell, and flow cytometry showed a significantly larger percentage of ceils in G0/G1 phase, a smaller one in S phase with 10 μmol/L clotrimazole treatment for 48 h. After lmin, CLO 10 μmol/L group, the Fluo-3/AM＇ s fluorescence intensity of PRMI 8226 and U266 cell lines were （448.3 ±32. 79）, （675.9±45.83）, respectively, and were all significantly larger thanthose of control group＇s（56.5 ±7.22）, （31.8 ±4. 54）, P 〈0. 05. Conclusion CLO can de- crease the proliferation of MM cells by inhibiting. The mechanism of growth-suppressive effect of elotrimazole may be blocked the cell cycle in G0/G1 phase by regulating the levels of [ Ca2＋ ] i..