title: Apoptosis sensitization by Euphorbia factor L1 in ABCB1-mediated multidrug resistant K562/ADR cells.
abstract: In this article, reversal activities of Euphorbia factor L1 (EFL1) against ABCB1-mediated multidrug resistance (MDR) and apoptosis sensitization in K562/ADR cells are reported. EFL1 decreased the IC50 values of anticancer agents in K562/ADR cells over-expressing ABCB1. However, EFL1 did not affect the IC50 values of anticancer agents in sensitive K562 cells. Additionally, EFL1 increased the intracellular accumulation of rhodamine 123 and doxorubicin in K562/ADR cells without affecting their accumulation in K562 cells. Furthermore, EFL1 sensitized the apoptosis triggered by vincristine in K562/ADR cells via mitochondrial pathway, as confirmed by Annexin V-FITC/PI detection and western blot. At the same time, EFL1 did not influence the apoptosis induced by vincristine in K562 cells. Western blot results showed that EFL1 did not affect the phosphorylation level of AKT and ERK in K562 and K562/ADR cells. Finally, EFL1 did not down-regulate protein expression of ABCB1.
authors.affiliation: School of Chinese Medicine, Hong Kong Baptist University, 7 Baptist University Road, Kowloon Tong, Kowloon, Hong Kong. hbchen@hkbu.edu.hk.
authors.forename: Jian-Ye
authors.initials: JY
authors.lastname: Zhang
authors.forename: Min-Ting
authors.initials: MT
authors.lastname: Lin
authors.forename: Tao
authors.initials: T
authors.lastname: Yi
authors.forename: Yi-Na
authors.initials: YN
authors.lastname: Tang
authors.forename: Lan-Lan
authors.initials: LL
authors.lastname: Fan
authors.forename: Xi-Cheng
authors.initials: XC
authors.lastname: He
authors.forename: Zhong-Zhen
authors.initials: ZZ
authors.lastname: Zhao
authors.forename: Hu-Biao
authors.initials: HB
authors.lastname: Chen
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000502:physiology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D020169:Caspases / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D004224:Diterpenes / Q000494:pharmacology*; D004317:Doxorubicin / Q000494:pharmacology; D018432:Drug Resistance, Multiple / Q000187:drug effects; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D004354:Drug Screening Assays, Antitumor; D004357:Drug Synergism; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D015870:Gene Expression; D006801:Humans; D020128:Inhibitory Concentration 50; D020014:K562 Cells; D010666:Phenylpropionates / Q000494:pharmacology*; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D014750:Vincristine / Q000494:pharmacology
chemical_list: C513055:ABCB1 protein, human; D018435:ATP Binding Cassette Transporter, Subfamily B; D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D004224:Diterpenes; D010666:Phenylpropionates; C559819:euphorbia factor L1; D014750:Vincristine; D004317:Doxorubicin; D051057:Proto-Oncogene Proteins c-akt; D048049:Extracellular Signal-Regulated MAP Kinases; D020169:Caspases