Fiche publication


Date publication

octobre 1998

Journal

European journal of haematology

Auteurs

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


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

Résumé

A number of small and lipophilic cations are able to reverse in vitro the resistance to anthracyclines and other natural products through their interaction with P-glycoprotein or P-gp. However, some modulators do not interact with P-gp. We have demonstrated in a previous a work, using confocal laser microspectrofluorometry, that quinine does not increase nuclear anthracycline uptake in multidrug-resistant Chinese hamster ovary LR73 cells. In this case the LR73 cells were transfected with the mdr1 gene. Moreover, quinine induced in these cells an increase of mdr1 gene expression. In the present study, we investigated verapamil and quinine for their ability to increase nuclear pirarubicin uptake in multidrug-resistant K562R and CEMR human leukemic cell lines. These two cell lines resist, respectively, to doxorubicin and vinblastine and both overexpress the P-gp. Verapamil was able to restore nuclear pirarubicin in both cell lines. On the other hand, quinine was unable to significantly increase nuclear pirarubicin uptake. Both modulators were able to restore pirarubicin sensitivity in both resistant cell lines. After treatment with quinine, mdr1 gene and P-gp expression was not significantly altered as observed previously in the LR73 cells. This suggest that the effect of quinine on mdr1 gene expression is dependent on the cell line studied. These data suggest that quinine could modify the molecular environment of anthracyclines and/or its binding to a possible cytoplasmic target, and that the mechanisms by which anthracyclines induce cell death, and ways by which chemotherapy fails in multidrug-resistant leukemic cells remain complex and are related to more than one target.

Mots clés

Animals, Antibiotics, Antineoplastic, metabolism, CHO Cells, Cell Death, drug effects, Cell Nucleus, metabolism, Cricetinae, Doxorubicin, analogs & derivatives, Drug Resistance, Multiple, genetics, Gene Transfer Techniques, Humans, K562 Cells, Leukemia, drug therapy, P-Glycoprotein, genetics

Référence

Eur. J. Haematol.. 1998 Oct;61(4):240-9