Department of Pharmacology & Clinical Pharmacology, The University of Auckland, Auckland, New Zealand.
Cancer Chemother Pharmacol. 2011 Sep;68(3):603-10. doi: 10.1007/s00280-010-1515-6. Epub 2010 Nov 30.
Chemotherapy of pancreatic cancer often fails due to the development of intrinsic and acquired resistance during drug treatment. Recent studies have suggested that MRP5 conferred resistance to first-line drugs 5-fluorouracil and gemcitabine by active efflux of drugs from the cell. Our aim was to evaluate whether curcumin could reverse this multi-drug resistance by inhibition of MRP5-mediated efflux.
MRP5 protein was detected and localized by immunocytochemistry using a monoclonal antibody in MRP5 over-expressing HEK293 (HEK293/MRP5) cells and two pancreatic cancer cell lines PANC-1 and MiaPaCa-2. The cellular accumulation of a specific MRP5 fluorescent substrate 2',7'-Bis(2-carboxyethyl)-5(6)-carboxyfluorescein (BCECF) into these cells was measured by flow cytometry and the cell proliferation determined by a 72-h CyQuant assay.
The cellular accumulation of BCECF in HEK293/MRP5 cells and in PANC-1 and MiaPaCa-2 cells was significantly increased by curcumin in a concentration-dependent manner. Curcumin and a MRP5 inhibitor MK571 had no apparent effects on cellular accumulation of BCECF in parental HEK293 cells. In the proliferation assays, curcumin caused a concentration-dependant increase in the sensitivity to the cytotoxic drug 5-fluorouracil in HEK293/MRP5 cells, PANC-1 and MiaPaCa-2 pancreatic cancer cells, but not in parental HEK293 cells.
Our results suggest that curcumin is an inhibitor of MRP5 and may be useful in the reversal of multi-drug resistance in pancreatic cancer chemotherapy.
由于在药物治疗过程中内在和获得性耐药的发展，胰腺癌的化疗经常失败。最近的研究表明，MRP5 通过将药物从细胞中主动排出，赋予了对一线药物 5-氟尿嘧啶和吉西他滨的耐药性。我们的目的是评估姜黄素是否可以通过抑制 MRP5 介导的外排来逆转这种多药耐药性。
使用单克隆抗体通过免疫细胞化学在 MRP5 过表达的 HEK293（HEK293/MRP5）细胞和两种胰腺癌细胞系 PANC-1 和 MiaPaCa-2 中检测和定位 MRP5 蛋白。通过流式细胞术测量这些细胞中特定的 MRP5 荧光底物 2'，7'-双（2-羧乙基）-5（6）-羧基荧光素（BCECF）的细胞内积累，并通过 72 小时 CyQuant 测定法测定细胞增殖。
姜黄素以浓度依赖的方式显着增加了 HEK293/MRP5 细胞以及 PANC-1 和 MiaPaCa-2 细胞中 BCECF 的细胞内积累。姜黄素和 MRP5 抑制剂 MK571 对亲本 HEK293 细胞中 BCECF 的细胞内积累没有明显影响。在增殖测定中，姜黄素导致 HEK293/MRP5 细胞、PANC-1 和 MiaPaCa-2 胰腺癌细胞对细胞毒性药物 5-氟尿嘧啶的敏感性呈浓度依赖性增加，但对亲本 HEK293 细胞没有影响。
我们的结果表明姜黄素是 MRP5 的抑制剂，可用于逆转胰腺癌化疗中的多药耐药性。
