Sugawara I, Akiyama S, Scheper R J, Itoyama S
Department of Pathology, Saitama Medical Center, Kamoda, Kawagoe, Japan.
Cancer Lett. 1997 Jan 15;112(1):23-31. doi: 10.1016/S0304-3835(96)04542-9.
MDR1 (P-glycoprotein), multidrug resistance-associated protein (MRP) and lung resistance protein (LRP) are associated with multidrug resistance in various cancer cells. It is known that P-glycoprotein and MRP are also expressed in several normal tissues. However, the exact location of LRP in normal tissues is still unclear. In order to obtain more insight into the physiological role of LRP, its expression in human normal tissues was examined by an immunohistochemical technique, using one monoclonal antibody, LRP-56. Reverse transcriptase-polymerase chain reaction (RT-PCR) was also utilized for several cell lines and fresh-frozen tissues. P-glycoprotein was found to be expressed in the kidney, adrenal, brain vessels, muscle, lung, pancreas, liver, intestine, placenta and testis. MRP was expressed in the kidney, adrenal, lung, pancreas, muscle, intestine, thyroid and prostate, and its distribution mostly overlapped with that of P-glycoprotein. Interestingly, MRP was not expressed in the liver. LRP at 110 kDa was expressed in the kidney, adrenal, heart, lung, muscle, thyroid, prostate, bone marrow and testis. These findings suggest that LRP as well as P-glycoprotein and MRP plays distinct roles in the physiology of various organs.
多药耐药蛋白1（P-糖蛋白）、多药耐药相关蛋白（MRP）和肺耐药蛋白（LRP）与多种癌细胞的多药耐药性相关。已知P-糖蛋白和MRP也在几种正常组织中表达。然而，LRP在正常组织中的具体定位仍不清楚。为了更深入了解LRP的生理作用，使用一种单克隆抗体LRP-56，通过免疫组织化学技术检测了其在人正常组织中的表达。逆转录聚合酶链反应（RT-PCR）也用于几种细胞系和新鲜冷冻组织。发现P-糖蛋白在肾脏、肾上腺、脑血管、肌肉、肺、胰腺、肝脏、肠道、胎盘和睾丸中表达。MRP在肾脏、肾上腺、肺、胰腺、肌肉、肠道、甲状腺和前列腺中表达，其分布大多与P-糖蛋白重叠。有趣的是，MRP在肝脏中不表达。110 kDa的LRP在肾脏、肾上腺、心脏、肺、肌肉、甲状腺、前列腺、骨髓和睾丸中表达。这些发现表明，LRP以及P-糖蛋白和MRP在各种器官的生理学中发挥着不同的作用。
