Evidence for reversal of multidrug resistance by quinine in LR73 cells without alteration of nuclear pirarubicin uptake and down-regulation of mdr1 gene expression.

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Date publication

novembre 1997

Journal

International journal of cancer

Auteurs

Membres identifiés du Cancéropôle Est :
Pr MORJANI Hamid, Dr LAHLIL Rachid


Tous les auteurs :
Belhoussine R, Morjani H, Lahlil R, Manfait M

Résumé

Confocal laser microspectrofluorometry was used to investigate restoration of nuclear pirarubicin (THP-DOX) accumulation and sensitivity by verapamil, quinine and S9788 in 2 variants of the Chinese hamster ovary cell lines LR73, selected for resistance to doxorubicin (LR73D) or transfected with the mdr1 gene (LR73R). The 2 resistant cell lines present a multidrug-resistance phenotype (MDR). Verapamil and S9788, which interact with P-glycoprotein (P-gp), were able to restore nuclear THP-DOX accumulation in LR73R and LR73D cells to a level equivalent to that in sensitive cells. On the other hand, quinine was unable to increase nuclear THP-DOX accumulation significantly even at a concentration of 50 microM. All modulators completely restored THP-DOX sensitivity in resistant cell lines. Our results also show that verapamil and S9788 allow high nuclear drug accumulation, whereas quinine did not affect nuclear accumulation. The effect of quinine on the mdr1 gene expression was determined by the use of reverse transcription coupled with polymerase chain reaction. After a 2 hr treatment with 20 microM of quinine, mdr1 gene expression increased slightly.

Mots clés

Animals, CHO Cells, drug effects, Cell Nucleus, metabolism, Cricetinae, Doxorubicin, analogs & derivatives, Drug Resistance, Multiple, Drug Resistance, Neoplasm, Gene Expression Regulation, drug effects, Genes, MDR, drug effects, P-Glycoprotein, drug effects, Piperidines, pharmacology, Quinine, pharmacology, Triazines, pharmacology, Verapamil, pharmacology

Référence

Int. J. Cancer. 1997 Nov;73(4):600-6