title: Down-regulatory mechanism of mammea E/BB from Mammea siamensis seed extract on Wilms' Tumor 1 expression in K562 cells.
abstract: BACKGROUND
  Wilms' tumor 1 (WT1) is a biological marker for predicting leukemia progression. In this study, mammea E/BB, an active compound from Saraphi (Mammea siamensis) seed extract was examined for its effect on down-regulatory mechanism of WT1 gene expression, WT1 protein and mRNA stability, and cell proliferation in K562 cell line.
  
  
  METHODS
  M. siamensis seeds were obtained from the region of Chiang Mai (North of Thailand). Mammea E/BB was extracted from seeds of M. siamensis. WT1 protein expression and stability were evaluated by Western blot analysis. WT1 mRNA stability was assessed by qRT-PCR. WT1-DNA binding and WT1 promoter activity were assayed by ChIP assay and luciferase-reporter assay, respectively. Cell cycle arrest was studied by flow cytometry.
  
  
  RESULTS
  Treatment with mammea E/BB led to down-regulation of WT1 expression. The suppression of WT1 expression did not involve protein and mRNA degradation. Rather, WT1 protein was down-regulated through disruption of transcriptional auto-regulation of the WT1 gene. Mammea E/BB inhibited WT1-DNA binding at the WT1 promoter and decreased luciferase activity. It also disrupted c-Fos/AP-1 binding to the WT1 promoter via ERK1/2 signaling pathway and induced S phase cell cycle arrest in K562 cells.
  
  
  CONCLUSIONS
  Mammea E/BB had pleotropic effects on kinase signaling pathways, resulting in inhibition of leukemia cell proliferation.
authors.affiliation: Department of Pharmaceutical Sciences, Faculty of Pharmacy, Chiang Mai University, Chiang Mai, 50200, Thailand.
authors.forename: Methee
authors.initials: M
authors.lastname: Rungrojsakul
authors.affiliation: Department of Chemistry, Faculty of Science, Chandrakasem Rajabhat University, Bangkok, 10900, Thailand.
authors.forename: Trinnakorn
authors.initials: T
authors.lastname: Katekunlaphan
authors.affiliation: Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand.
authors.forename: Aroonchai
authors.initials: A
authors.lastname: Saiai
authors.affiliation: Department of Pharmaceutical Sciences, Faculty of Pharmacy, Chiang Mai University, Chiang Mai, 50200, Thailand.
authors.forename: Chadarat
authors.initials: C
authors.lastname: Ampasavate
authors.affiliation: Department of Pharmaceutical Sciences, Faculty of Pharmacy, Chiang Mai University, Chiang Mai, 50200, Thailand.
authors.forename: Siriporn
authors.initials: S
authors.lastname: Okonogi
authors.affiliation: Department of Biochemistry and Molecular Medicine, UC Davis School of Medicine, Sacramento, CA, 95817, USA. casweeney@ucdavis.edu.|UC Davis Cancer Center, Research Building III, Room 1100A, 4645 2nd Avenue, Sacramento, CA, 95817, USA. casweeney@ucdavis.edu.
authors.forename: Colleen A
authors.initials: CA
authors.lastname: Sweeney
authors.affiliation: Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, 50200, Thailand. sanuchapreeda@gmail.com.|Division of Clinical Microscopy, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, 50200, Thailand. sanuchapreeda@gmail.com.
authors.forename: Songyot
authors.initials: S
authors.lastname: Anuchapreeda
mesh_terms: D049109:Cell Proliferation / Q000187:drug effects; D003374:Coumarins / Q000737:chemistry / Q000494:pharmacology*; D015536:Down-Regulation / Q000187:drug effects*; D015973:Gene Expression Regulation, Leukemic / Q000187:drug effects*; D006801:Humans; D020014:K562 Cells; D031252:Mammea / Q000737:chemistry*; D015394:Molecular Structure; D010936:Plant Extracts / Q000494:pharmacology*; D020871:RNA Stability / Q000187:drug effects; D012334:RNA, Neoplasm; D025721:WT1 Proteins / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D003374:Coumarins; C554271:Mammea E-BB compound; D010936:Plant Extracts; D012334:RNA, Neoplasm; D025721:WT1 Proteins
keywords: AP-1; Cell cycle arrest; ERK1/2; K562 cells; Mammea E/BB; Mammea siamensis; WT1