2-甲氧基雌二醇诱导骨髓瘤细胞分化的分子机制研究

目的研究2-甲氧基雌二醇（2ME2）诱导骨髓瘤细胞系分化的分子机制方法应用细胞形态学方法、流式细胞术分析、ELISA法和RT-PCR疗法，观察2ME2对于骨髓瘤细胞系LP-1、CZ-1、NCI-H929细胞分化的影响，同时检测细胞分化时X盒结合蛋白1（XBP-1）mRNA的改变情况。继而采用XBP-1、Blimp-1、pax-5硫代反义寡核苷酸（ASODN）作为干预手段，观察其对于2ME2诱导骨髓瘤细胞系分化作用的影响及mRNA水平的变化。结果2ME2可诱导骨髓瘤细胞系LP-1、CZ-1、NCI-H929细胞向成熟阶段分化，伴随着细胞分化的过程XBP-1 mRNA的表达水平上调。XBP-1 ASODN和Blimp-1 ASODN可以部分抑制2ME2促骨髓瘤细胞系分化作用，而pax-5 ASODN可以加强2ME2促骨髓瘤细胞系分化作用。经pax-5 ASODN作用72h，经形态学观察，细胞向成熟阶段分化，表现为细胞胞核缩小，胞浆丰富，核浆比例下降，核仁减少或消失，核染色质变粗、变密；细胞表面标志CD49e表达率增高；同时细胞分泌轻链蛋白升高经Blimp-1 ASODN作用72h后，pax-5 mRNA水平显著升高；而XBP-1 mRNA水平下降。结论2ME2可诱导骨髓瘤细胞系LP-1、CZ-1、NCI-H929细胞向成熟阶段分化，伴随着细胞的分化XBP-1 mRNA的表达水平上调，Blimp-1可通过抑制pax-5 mRNA的表达上调XBP-1 mRNA的表达水平，促进骨髓瘤细胞分化。

Molecular mechanism of myeloma cell line differentiation induced by 2-methoxyestradiol

Objective To study the molecular mechanism of differentiation induction by 2-methoxyestradiol(2ME2) of myeloma cell lines. Methods Differentiation induction effect on myeloma cell lines LP-1,CZ-1 and NCI-H929 which were incubated with 2ME2 and XBP-1,Blimp-1,pax-5 phosporothioated antisense oligodeoxynucleotide (ASODN) was evaluated by cell morphology, CD49e expression, quantitation of light chain secretion, and the level of pax-5 and XBP-1 mRNA expression. Results 2ME2 caused morpholo-gical, immunophenotypic and the supernatant light chain secretion changes typical of differentiation in all the three myeloma cell lines. 2ME2 up-regulated the XBP-1 mRNA expression. XBP-1 and Blimp-1 ASODNs partially inhibited the differentiation of LP-1, CZ-1, NCI-H929 cells induced by 2ME2; whereas pax-5 ASODN did the contrary. After incubated with pax-5 ASODN for 72 hours, LP-1,CZ-1,NCI-H929 cells exhibited characteristic morphologic feature of differentiation. The expression of CD49e was increased statistically (P<0.05) . Light chain secretion in the supernatant was also increased statistically (P<0.05). After incubation with Blimp-1 ASODN,the level of XBP-1 mRNA was declined,while the level of pax-5 mRNA increased. Conclusion 2ME2 could induce cell differentiation and up-regulate XBP-1 mRNA expression in myeloma cell lines. Blimp-1 could help 2ME2 with inducing differentiation of myeloma cells through downregulating pax-5 mRNA and upregulating XBP-1 mRNA.