Genistein modulates the decreased drug accumulation in non-P-glycoprotein mediated multidrug resistant tumour cells

Abstract

In tumour cells the pharmacological basis for multidrug resistance (MDR) often appears to be a reduced cellular cytostatic drug accumulation caused by the drug efflux protein, P-glycoprotein (Pgp MDR), or by other drug transporters (non-Pgp MDR). Here we report the reversal of the decreased daunorubicin (DNR) accumulation in five non-Pgp MDR cell lines (GLC4/ADR, SW-1573/2R120, HT1080/DR4, MCF7/Mitox and HL60/ADR) by genistein. Genistein inhibited the enhanced DNR efflux in the GLC4/ADR cells. In these cells the decreased VP-16 accumulation was also reversed by genistein. Three other (iso)flavonoids biochanin A, apigenin and quercetin also increased the DNR accumulation in the GLC4/ADR cells. In contrast to the effects on non-Pgp MDR cells, 200 microM genistein did not increase the reduced DNR accumulation in three Pgp MDR cell lines (SW-1573/2R160, MCF7/DOX40 and KB8-5) or in the parental cell lines. In conclusion the use of genistein provides a means to probe non-Pgp related drug accumulation defects. Images Figure 1 Figure 6

P‐glycoprotein (PGP) and lung resistance‐related protein (LRP) expression and function in leukaemic blast cells

“…Moreover, unlike PGPresistant cell lines, it has been shown that in LRP, as well as MRP over-expressed cell lines, cyclosporine A, or cyclosporine derivatives including SDZ PSC 833 (PSC), could not restore drug accumulation (Kuiper et al, 1990;Barrand et al, 1993). On the other hand, it has been shown that some other drugs, such as verapamil, amiodarone or genistein, had a moderate activity (Kuiper et al, 1990;Barrand et al, 1993;Versantvoort et al, 1993;Cole et al, 1994;Van der Graaf et al, 1994). The aim of our work was to study PGP, LRP and MRP expression in leukaemic blast cells, and to investigate their relationship with the cells' ability in accumulating DNR, or in retaining Rhodamine 123, in the presence or absence of the MDR reversal agent SDZ PSC 833.…”

ATP‐dependent efflux of calcein by the multidrug resistance protein (MRP): no inhibition by intracellular glutathione depletion

“…contrast to MRP mediated MDR, is readily reversed by drugs such as verapamil, cyclosporin A and the cyclosporin analogue PSC833 [9]. A potent specific inhibitor of MRP mediated daunorubicin (DNR) transport is the isoflavonoid genistein [9].…”

The modulating effect of PSC 833, cyclosporin A, verapamil and genistein on in vitro cytotoxicity and intracellular content of daunorubicin in childhood acute lymphoblastic leukemia

“…11,18 Expression of drug resistance proteins Expression of drug resistance proteins was measured using an optimized method for childhood ALL cells as recently described. 19 The expression of P-gp was detected by MRK16 (mouse IgG2a, 5 g/ml; Kamiya Biomedical Company, Thousand Oaks CA, USA).…”

“…These data confirm earlier reports by others and validate the presently applied method. 11,18 The effects of the modulators on the accumulation and retention of DNR in childhood ALL cells was only small in the majority of cases. As shown in Figure 3, the median change in accumulated DNR content after 60 min of uptake was +2.5% for 2 M PSC 833 (range −5% to +24%; n = 42), +2% for 4 M CsA (range −9% to +22%; n = 25), +11.5% for 6 M Vp (range −17% to +95%; n = 14) and −2.5% for 25 M genistein (range −10% to +10%; n = 10) compared with the accumulated DNR content in the absence of modulators.…”

“…Genistein has been found to increase the accumulation and retention of the anthracycline daunorubicin (DNR) in non-P-gp but not in P-gp expressing cell lines. 11 However, the modulating effect of genistein was only observed at a high concentration, which was lethal to the cells in a 5-day culture assay. A less cytotoxic modulator of MDR may be PSC 833, a new cyclosporin analogue.…”