title: Anti-proliferative and differentiation-inducing activities of the green tea catechin epigallocatechin-3-gallate (EGCG) on the human eosinophilic leukemia EoL-1 cell line.
abstract: A novel approach for the treatment of leukemia is the differentiation therapy in which immature leukemia cells are induced to attain a mature phenotype when exposed to differentiation inducers, either alone or in combinations with other chemotherapeutic or chemopreventive drugs. Over the past decade, numerous studies indicated that green tea catechins (GTC) could suppress the growth and induce apoptosis on a number of human cancer cell lines. However, the differentiation-inducing activity of GTC on human tumors remains poorly understood. In the present study, the effect of the major GTC epigallocatechin-3-gallate (EGCG) on the proliferation and differentiation of a human eosinophilc leukemic cell line, EoL-1, was examined. Our results showed that EGCG suppressed the proliferation of the EoL-1 cells in a dose-dependent manner, with an estimated IC(50) value of 31.5 microM. On the other hand, EGCG at a concentration of 40 microM could trigger the EoL-1 cells to undergo morphological differentiation into mature eosinophil-like cells. Using RT-PCR and flow cytometry, it was found that EGCG upregulated the gene and protein expression of two eosinophil-specific granule proteins, the major basic protein (MBP) and eosinophil peroxidase (EPO), in EoL-1 cells. Taken together, our findings suggest that EGCG can exhibit anti-leukemic activity on a human eosinophilic cell line EoL-1 by suppressing the proliferation and by inducing the differentiation of the leukemia cells.
authors.affiliation: Department of Biochemistry, The Chinese University of Hong Kong, Shatin, China.
authors.forename: H L
authors.initials: HL
authors.lastname: Lung
authors.forename: W K
authors.initials: WK
authors.lastname: Ip
authors.forename: C K
authors.initials: CK
authors.lastname: Wong
authors.forename: N K
authors.initials: NK
authors.lastname: Mak
authors.forename: Z Y
authors.initials: ZY
authors.lastname: Chen
authors.forename: K N
authors.initials: KN
authors.lastname: Leung
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D001798:Blood Proteins / Q000096:biosynthesis / Q000235:genetics; D002392:Catechin / Q000031:analogs & derivatives* / Q000494:pharmacology*; D002454:Cell Differentiation; D002455:Cell Division; D004305:Dose-Response Relationship, Drug; D047091:Eosinophil Granule Proteins; D047209:Eosinophil Peroxidase; D006131:Growth Inhibitors / Q000494:pharmacology; D006801:Humans; D017681:Hypereosinophilic Syndrome / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D007700:Kinetics; D010544:Peroxidases / Q000096:biosynthesis / Q000235:genetics; D012334:RNA, Neoplasm / Q000096:biosynthesis; D012260:Ribonucleases; D014407:Tumor Cells, Cultured
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D001798:Blood Proteins; D047091:Eosinophil Granule Proteins; D006131:Growth Inhibitors; D012334:RNA, Neoplasm; D002392:Catechin; C045651:epigallocatechin gallate; D047209:Eosinophil Peroxidase; D010544:Peroxidases; D012260:Ribonucleases