阿霉素诱导的骨髓瘤细胞化疗耐药的分子机制分析

本研究旨在探讨阿霉素诱导的骨髓瘤细胞RPMI8226化疗耐药的分子机制,分析Notch信号过度活化在化疗耐药机制中的作用.以浓度梯度递增法建立耐阿霉素的骨髓瘤细胞系RPMI8226/DOX,针对化疗耐药的瘤细胞RPMI8226/DOX,用RT-PCR法检测细胞耐药前后Notch2、Jagged1、Jagged2、HES1基因表达变化;Western blot检测耐药细胞系与敏感细胞系P-170蛋白表达变化;ELISA方法分析IL-6、VEGF水平变化.结果显示,Notch2、Jagged1、Jagged2基因随着耐药程度的增高表达逐渐增高,而HES1则相反,随着耐药程度增高表达逐渐减低.P-170蛋白随着耐药程度的增高表达逐渐增高.耐药细胞组培养上清中细胞因子VEGF和IL-6水平显著高于普通培养组.结论：建立的人骨髓瘤细胞系RPMI8226/DOX可以作为骨髓瘤耐药研究的有效模型,Notch信号通路的活化与多发性骨髓瘤的耐药密切相关,Notch信号通路有望成为多发性骨髓瘤治疗的新靶点.

Molecular Mechanism of Doxorubicin Resistance in Multiple Myeloma Cell Line

This study was aimed to investigate the molecular mechanism of doxorubicin resistance in multiple myeloma cell line and certify the effect of Notch signal over-expression on drug resistance of myeloma cells.The doxorubicin RPMI 8226 cell line （RPMI8226/DOX） was established by culturing 8226 cells with continuous low concentration and intermittent gradually-increasing-concentration of doxorubicin in vitro,the mRNA expression of Notch2,Jagged1,Jagged2,HES1 were measured by RT-PCR and the P-170 protein expression was detected by Western blot in RPMI 8226 cell line; the changes of IL-6 and VEGF were tested by ELISA.The results showed that the Notch mRNA expression （Notch2,Jagged1,Jagged2） increased gradually along with the increase of chemotherapeutic drug resistance,but the expression of HESI mRNA gradually decreased along with the increase of drug resistance.The expression level of P-170 protein was upregulated gradually along with the increase of drug resistance.The level of VEGF and IL-6 in culture supernatants of RPMI8226/DOX was higher than that in RPMI 8226.It is concluded that the establishment of RPMI 8226/DOX cell line is a useful model to analyze the mechanism of chemotherapeutic drug resistance in multiple myeloma,Notch activation is closely correlated with the drug resistance of multiple myeloma and Notch signaling may to be used as a new target for multiple myeloma treatment.