Acquired resistance to chloroquine in human CEM T cells is mediated by multidrug resistance–associated protein 1 and provokes high levels of cross‐resistance to glucocorticoids

Abstract

Objective. To explore the onset and molecular mechanism of resistance to the antimalarial diseasemodifying antirheumatic drug (DMARD) chloroquine (CQ) in human CEM T cells.Methods. Human CEM cells were used as an in vitro model system to study the development of CQ resistance by growing cells in stepwise increasing concentrations of CQ.Results. Over a period of 6 months, CEM cell lines developed 4-5-fold resistance to CQ. CQ resistance was associated with the specific overexpression of multidrug resistance-associated protein 1 (MRP-1), an ATP-driven drug efflux pump. This was illustrated by 1) overexpression of MRP-1 by Western blotting and 2) the complete reversal of CQ resistance by the MRP-1 transport inhibitors MK571 and probenecid. Importantly, CQ-resistant CEM cells retained full sensitivity to other DMARDs, including methotrexate, leflunomide, cyclosporin A, and sulfasalazine, but exhibited a high level of cross-resistance (>1,000-fold) to the glucocorticoid dexamethasone. The mechanistic basis for the latter was associated with aberrant signaling via the cAMP-protein kinase A pathway, since the cAMP-inducing agent forskolin reversed dexamethasone resistance. Finally, CQ-resistant CEM cells displayed a markedly reduced capacity to release proinflammatory cytokines (tumor necrosis factor ␣) and chemokines (interleukin-8).Conclusion. Induction of overexpression of the multidrug resistance efflux transporter MRP-1 can emerge after long-term exposure to CQ and results in CQ resistance and collateral resistance to dexamethasone. These findings warrant further detailed investigations into the possible role of MRP-1 and other members of the superfamily of drug efflux pumps in diminishing the efficacy of DMARDs in rheumatoid arthritis treatment.

InactivatingPSMB5Mutations and P-Glycoprotein (Multidrug Resistance-Associated Protein/ATP-Binding Cassette B1) Mediate Resistance to Proteasome Inhibitors: Ex Vivo Efficacy of (Immuno)Proteasome Inhibitors in Mononuclear Blood Cells from Patients with Rheumatoid Arthritis

“…Human monocytic-macrophage THP1 cells with various levels of acquired resistance to BTZ were selected as described previously (Oerlemans et al, 2008). Multiple human cell lines were selected based on their known expression of ABC transporters, Pglycoprotein/MDR1 (CEM/VLB) (Zamora et al, 1988), multidrug resistance-associated protein 1 (CEM/CHQ, 2008/MRP1) (Scheffer et al, 2000;Oerlemans et al, 2006), MRP2 (2008/MRP2) (Scheffer et al, 2000), MRP3 (2008/MRP3) (Scheffer et al, 2000), MRP4 (HEK293/MRP4) (Wielinga et al, 2002), MRP5 (HEK293/MRP5) (Wielinga et al, 2002), and breast cancer resistance protein (BCRP) (CEM/SSZ and MCF7/MR) (Taylor et al, 1991;van der Heijden et al, 2004). Cell cultures were maintained in RPMI 1640 medium supplemented with 10% fetal calf serum, 2 mM L-glutamine, and 1000 U/ml penicillin/streptomycin.…”

“…The growth inhibitory effects of BTZ, carfilzomib, ONX-0912, and ONX-0914 were analyzed essentially as described previously (Shafran et al, 2005;Oerlemans et al, 2006). In brief, for suspension cell cultures, 1.25 ϫ 10 5 cells/ml were plated in individual wells of a 24-well cell culture plates containing an increasing concentration of each proteasome inhibitor.…”

Involvement of breast cancer resistance protein expression on rheumatoid arthritis synovial tissue macrophages in resistance to methotrexate and leflunomide

“…From oncology research, it has been established that specific cell membrane-associated drug efflux transporters belonging to the family of ATP-binding cassette (ABC) proteins, notably P-glycoprotein (ABCB1), multidrug resistance-associated protein 1 (MRP-1) through MRP-5 (ABCC1 through ABCC5), and breast cancer resistance protein (BCRP; ABCG2), can be induced upon therapy with various anticancer drugs to confer a phenomenon known as acquired (multi)drug resistance (6)(7)(8)(9). Studies conducted in our laboratory have shown that acquired resistance to the DMARDs sulfasalazine and chloroquine could be mediated by the increased expression of the ABC transporters BCRP and MRP-1, respectively (10)(11)(12). Furthermore, it was very recently demonstrated that LEF is a high-affinity substrate for BCRP (13).…”

“…MTX and the antimalarial agent chloroquine are among the DMARD substrates of MRP-1, and expression of this transporter may thus confer resistance to these drugs (6,12,44). However, since MRP-1 levels in synovial T cells are rather moderate, a major contribution to a reduced response to MTX or antimalarial drugs remains elusive.…”

Characterization of an ABCG-Like Transporter from the Protozoan Parasite Leishmania with a Role in Drug Resistance and Transbilayer Lipid Movement

“…MRP1 (ABCC1) transports both chloroquine and mefloquine (23,38). P-glycoprotein (MDR1, ABCB1) interacts with mefloquine (3).…”