脐血血浆对K562细胞增殖抑制作用研究

Proliferation inhibition in human erythroleukemia cell line K562 by cord blood plasma

目的 研究脐血血浆 (CBP)对人红白血病细胞株K5 6 2增殖影响及可能机制。方法 台盼蓝拒染法绘制生长曲线 ;MTT法检测CBP对K5 6 2细胞的抑制作用 ;流式细胞术分析细胞周期变化 ;免疫细胞化学方法检测增殖相关核抗原 (PCNA ,Ki 6 7)表达。结果 细胞生长曲线可见CBP作用 2 4h即观察到抑制作用 ,随时间增加 ,抑制作用更加明显 ,有非常显著性差异 (P <0 .0 1 )。MTT法结果与生长曲线结果相符。CBP作用 3d后 ,S期细胞数减少 ,G0 /G1 期细胞增多 ,有显著性差异 (P <0 .0 5 ) ,并出现G0 /G1 期凋亡细胞。CBP作用后 ,K5 6 2细胞增殖相关核抗原PCNA、Ki 6 7表达阳性程度降低 ,有显著性差异 (P <0 .0 5 )。结论 CBP对K5 6 2细胞增殖有明显抑制作用 ,与浓度、时间正相关 ;其机制可能与诱导凋亡、下调PCNA、Ki 6 7表达 。

Objective To research the proliferation inhibition effect of cord blood plasma (CBP) on human erythroleukemia cell line K562 and its mechanism.Methods Trypan blue counting assay was used to draw the K562 growth curve; MTT assay was used to measure the inhibition effect of CBP on K562 cells; flow cytometry technique was used to examine the cell cycle of K562 cells after treatment with CBP; immunohistochemistry assay was used to detect the expression of PCNA, Ki 67 of K562 after treatment with CBP.Results K562 cells growth curve showed that inhibition appeared after 24 hours of CBP treatment;the inhibition effect became more obvious and marked ( P <0.01)after 6 days of CBP treatment.The inhibition effect increased ( P <0.01)as CBP concentration increased.The result of the MTT assay was in agreement with the growth curve.The results of examining the cell cycle showed that the changes,S phase cell number after 3 days of treatment by CBP(10%, 20%) was decreased and G 0/G 1 phase cell number was increased;meanwhile,G 0/G 1 phase apoptosis cells appeared in the two groups, the ratios being 6%.The PCNA and Ki 67 expression proportions after 3 days of treatment decreased;the differences between CBP treated groups (each concentration) and the control group were significant ( P <0.05).Conclusions The inhibition effect of CBP on K562 cell line is clear, and is in direct proportion to time and CBP concentration. The mechanism of CBP inhibition on K562 cell growth is probably related to the inducing of apoptosis and decreasing PCNA, Ki 67 expression,the latter leads to lower cell proliferating activity and little DNA synthesis.