汉防己甲素衍生物 H1 通过抑制 P-糖蛋白的转运功能和表达逆转 P-糖蛋白介导的多药耐药。

H1, a novel derivative of tetrandrine reverse P-glycoprotein-mediated multidrug resistance by inhibiting transport function and expression of P-glycoprotein.

机构信息

Department of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, 1 Xian Nong Tan Street, 100050 Beijing, China.

出版信息

Cancer Chemother Pharmacol. 2011 May;67(5):1017-25. doi: 10.1007/s00280-010-1397-7. Epub 2010 Jul 17.

DOI:10.1007/s00280-010-1397-7

PMID:20640574

Abstract

PURPOSE

H1 is a novel derivative of tetrandrine (Tet). Here we investigate the ability of H1 to reverse P-glycoprotein (Pgp)-mediated multidrug resistance (MDR) and its mechanisms.

METHODS

KBv200, MCF-7/adr and their parental sensitive cell lines KB, MCF-7 were used for reversal study. The intracellular accumulation and efflux studies with Pgp substrates of doxorubicin and rhodamine 123 were determined by flow cytometry. The expression of Pgp was investigated by Western blot and RT-PCR analysis. ATPase activity of Pgp was performed by Pgp-Glo(™) assay systems. The ubiquitination level of Pgp was determined by immunoprecipitation analysis. The effect of ERK1/2 on Pgp expression in KBv200 cells were investigated by RNA interference.

RESULTS

H1 significantly potentiated the sensitivity of Pgp substrates in KBv200 and MCF-7/adr cells, but not in parental cells KB and MCF-7. H1 inhibited Pgp expression in KBv200 cells in a dose-dependent manner, but had no effect on MDR1 expression. Further studies showed that H1 prompted the degradation of Pgp and decreased Pgp protein half-life by enhancing the ubiquitination of Pgp, which may be related to downregulated MEK-ERK signal pathway. We also found H1 inhibited ATPase activity of Pgp in a dose-dependent manner.

CONCLUSIONS

H1 is an effectively and potential agent in reversing Pgp-mediated MDR by inhibiting the transport function and expression of Pgp.

摘要

目的

H1 是汉防己甲素（Tet）的一种新型衍生物。本研究旨在探讨 H1 逆转 P-糖蛋白（Pgp）介导的多药耐药（MDR）的能力及其机制。

方法

采用 KBv200、MCF-7/adr 及其亲本敏感细胞系 KB、MCF-7 进行逆转研究。采用流式细胞术测定阿霉素和罗丹明 123 的 Pgp 底物的细胞内积累和外排研究。采用 Western blot 和 RT-PCR 分析检测 Pgp 的表达。采用 Pgp-Glo（™）测定系统测定 Pgp 的 ATP 酶活性。通过免疫沉淀分析测定 Pgp 的泛素化水平。采用 RNA 干扰研究 ERK1/2 对 KBv200 细胞中 Pgp 表达的影响。

结果

H1 显著增强了 KBv200 和 MCF-7/adr 细胞中 Pgp 底物的敏感性，但对亲本细胞 KB 和 MCF-7 没有影响。H1 以剂量依赖性方式抑制 KBv200 细胞中 Pgp 的表达，但对 MDR1 表达没有影响。进一步的研究表明，H1 通过增强 Pgp 的泛素化来促使 Pgp 的降解并降低 Pgp 蛋白半衰期，这可能与下调的 MEK-ERK 信号通路有关。我们还发现 H1 以剂量依赖性方式抑制 Pgp 的 ATP 酶活性。