title: Pectinesterase inhibitor from jelly fig (Ficus awkeotsang Makino) achene induces apoptosis of human leukemic U937 cells.
abstract: The antitumor activity of pectinesterase inhibitor (PEI), a group of cationic polypeptides, from jelly fig (Ficus awkeotsang Makino) achene was first examined as a treatment for leukemia in this study. PEI displayed strong growth inhibition against human leukemic U937 cells via induction of apoptosis in a dose- and time-dependent manner. At a level of 50 microg/mL, PEI inhibited 90% of cell growth, and the concentration of PEI required to induce 50% of cell viability (LC50) was about 180 microg/mL. Meanwhile, cell cycle arrest at G2/M phase was observed when cells were incubated with 100 microg PEI/mL for 24 h. PEI displayed a dose-dependent influence on mitochondria transmembrane potential (MTP, delta psi m) of cells when detected by a flow cytometry. MTP of more than 50% cells was reduced when cells were incubated with PEI at levels higher than 50 microg PEI/mL for 24 h. In addition, PEI upregulated caspase-3 activity. Taken together, PEI potently inhibited the proliferation of human leukemic U937 cells via cell cycle arrest and apoptosis in association with MTP reduction and caspase-3 activation, respectively, and showed therapy potential for U937 cells.
authors.affiliation: Graduate Institute of Food Science and Technology, National Taiwan University, Taipei.
authors.forename: Jia-Huei
authors.initials: JH
authors.lastname: Chang
authors.forename: Yuh-Tai
authors.initials: YT
authors.lastname: Wang
authors.forename: Hung-Min
authors.initials: HM
authors.lastname: Chang
mesh_terms: D017304:Annexin A5 / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D002265:Carboxylic Ester Hydrolases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D030681:Ficus / Q000737:chemistry*; D005638:Fruit / Q000737:chemistry*; D006801:Humans; D007938:Leukemia / Q000378:metabolism / Q000473:pathology*; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D020298:U937 Cells
chemical_list: D017304:Annexin A5; D004791:Enzyme Inhibitors; D002265:Carboxylic Ester Hydrolases; C022323:pectinesterase; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases