title: Reversal of cancer multidrug resistance by tea polyphenol in KB cells.
abstract: Tea polyphenols, (-)-epigallocatechin gallate in particular, were examined for their modulating effects on the drug resistance KB-A-1 cells and drug sensitive KB-3-1 cells. Both KB-3-1 and KB-A-1 cells were equally sensitive to tea polyphenol and (-)-epigallocatechin gallate. When 10 microgram/ml (-)-epigallocatechin gallate or 40 microgram/ml tea polyphenol were present simultaneously with doxorubicin, the IC50 of doxorubicin on KB-A-1 cells decreased from 10.3 +/- 0.9 microgram/ml to 4.2 +/- 0.2 or 2.0 +/- 0.1 microgram/ml. Tea polyphenol and (-)-epigallocatechin gallate enhanced the cytotoxicity of doxorubicin on KB-A-1 cells by 5.2 and 2.5 times, respectively, but did not show a modulating effect on KB-3-1 cells. Both tea polyphenol and (-)-epigallocatechin gallate showed reversal effects on the multidrug resistance phenotype.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, Institute of Biochemistry, East China University of Science and Technology, Shanghai 200237, PR China.
authors.forename: Y
authors.initials: Y
authors.lastname: Mei
authors.forename: D
authors.initials: D
authors.lastname: Wei
authors.forename: J
authors.initials: J
authors.lastname: Liu
mesh_terms: D028241:Camellia sinensis; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004317:Doxorubicin / Q000494:pharmacology*; D018432:Drug Resistance, Multiple; D005419:Flavonoids; D006801:Humans; D007624:KB Cells / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D010636:Phenols / Q000494:pharmacology*; D011108:Polymers / Q000494:pharmacology*; D059808:Polyphenols; D011336:Probability; D012680:Sensitivity and Specificity
chemical_list: D005419:Flavonoids; D010636:Phenols; D011108:Polymers; D059808:Polyphenols; D004317:Doxorubicin