Premium
Impact of BCRP/MXR, MRP1 and MDR1/P‐Glycoprotein on thermoresistant variants of atypical and classical multidrug resistant cancer cells
Author(s) -
Stein Ulrike,
Lage Hermann,
Jordan Andreas,
Walther Wolfgang,
Bates Susan E.,
Litman Thomas,
Hohenberger Peter,
Dietel Manfred
Publication year - 2001
Publication title -
international journal of cancer
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.475
H-Index - 234
eISSN - 1097-0215
pISSN - 0020-7136
DOI - 10.1002/ijc.10131
Subject(s) - abcg2 , multiple drug resistance , atp binding cassette transporter , p glycoprotein , mitoxantrone , biology , rhodamine 123 , phenotype , multidrug resistance associated proteins , efflux , cancer research , transporter , drug resistance , gene , pharmacology , microbiology and biotechnology , genetics , chemotherapy
The impact of the ABC transporters breast cancer resistance protein/mitoxantrone resistance associated transporter (BCRP/MXR), multidrug resistance‐associated protein 1 (MRP1) and multidrug resistance gene‐1/P‐glycoprotein ( MDR1 /PGP) on the multidrug resistance (MDR) phenotype in chemoresistance and thermoresistance was investigated in the parental human gastric carcinoma cell line EPG85‐257P, the atypical MDR subline EPG85‐257RNOV, the classical MDR subline EPG85‐257RDB and their thermoresistant counterparts EPG85‐257P‐TR, EPG85‐257RNOV‐TR and EPG85‐257RDB‐TR. Within the atypical MDR subline EPG85‐257RNOV expression of BCRP/MXR and of MRP1 were clearly enhanced (vs. parental and classical MDR lines). MDR1 /PGP expression was distinctly elevated in the classical MDR subline EPG85‐257RDB ( vs . parental and atypical MDR sublines). In all thermoresistant counterparts basal expression of BCRP/MXR, MRP1 and MDR1 /PGP was increased relative to thermosensitive sublines. Although it could be shown that the overexpressed ABC transporters were functionally active, however, no decreased drug accumulations of doxorubicin, mitoxantrone and rhodamine 123 were observed. Thus, expression of BCRP/MXR, MRP1 and MDR1 /PGP was found to be dependent on the appropriate type of chemoresistance; correlating with a classical or atypical MDR phenotype. Within the thermoresistant variants, however, the increase in ABC transporter expression did obviously not influence the MDR phenotype. © 2001 Wiley‐Liss, Inc.