鬼臼叉甙诱导HL－60细胞分化时c－myc蛋白的表达

目的：观察小剂量鬼臼叉甙对ＨＬ－６０细胞的诱导分化作用和对ｃ－ｍｙｃ蛋白表达的影响。方法：应用加入鬼臼叉甙（ＶＰ－１６）和维甲酸（ＲＡ）的含２０％小牛血清的培养基培养人类早幼粒细胞株（ＨＬ－６０），分别在培养后１、２、４、６ｄ测定细胞各时相的ｃ－ｍｙｃ蛋白水平。结合细胞形态、细胞化学和氯化硝基四氮唑蓝（ＮＢＴ）还原试验，观察ＶＰ－１６、ＲＡ对ＨＬ－６０细胞的诱导分化作用及其与ｃ－ｍｙｃ蛋白表达的关系。结果：与ＲＡ一样，小剂量ＶＰ－１６能诱导ＨＬ－６０细胞向粒系分化。并且在ＨＬ－６０细胞分化过程中ｃ－ｍｙｃ蛋白水平明显降低。ＶＰ－１６处理的ＨＬ－６０细胞其ｃ－ｍｙｃ蛋白降低与其诱导分化作用呈负相关。结论：实验结果提示，ｃ－ｍｙｃ原癌基因表达的变化可能是ＶＰ－１６诱导ＨＬ－６０细胞分化的机制之一。

Expression of C-myc Proto-oncogene during Differentiation of HL-60 Cells Treated with VP-16

This study aimed to observe the effect of low-dose etoposide (VP-16) on the induction of differentiation of HL-60 cells and the expression of c-myc protein. METHODS:HL-60 cells were cultrued in RPMI 1640 medium containing 20% calf serum. For experiments, the medium was supplemented with VP-16 and retinoic acid (RA),respectively. c-myc protein levels of every stage of cell growth were determined at day 1,2,4 and 6 affer culture with method of 3Amino-9 Ethyl-Carbazae. Combined with the parameters of cell morphology, NBT reduction activity and cytochemistric data, we observed the effect of VP-16 and RA on the induction of defferentiation of HL-60 cells and thier relation to c-myc protein expression. RESULTS:Low-dose VP-16 induces HL-60 cells to differentiate to mature granulocytes. The c-myc protein levels decreased during differentiation of HL-60 cells,but it was correlated negatively to the induction of differentiation of HL-60 cells treated with VP-16. CONCLUSIONS:The changes in expression of cmyc protein may be a link in mechanism that induces differentiation of HL-60 cells treated with VP-16.