title: Ethyl acetate extract from Glycosmis parva leaf induces apoptosis and cell-cycle arrest by decreasing expression of COX-2 and altering BCL-2 family gene expression in human colorectal cancer HT-29 cells.
abstract: BACKGROUND
  Glycosmis parva Craib (Rutaceae) is reported to have cytotoxic and anti-inflammatory activities by decreasing COX-2 expression.
  
  
  OBJECTIVE
  To investigate the effect of G. parva on human colorectal cancer cells expressing COX-2, HT-29 cells.
  
  
  METHODS
  HT-29 cells were treated with ethyl acetate extract from the leaves of G. parva (GPE 6.25-100 µg/ml) for 24-72 h. Cell viability was evaluated by the resuzurin reduction assay. An apoptotic study was performed using annexinV/FITC-PI staining. The cell-cycle pattern was investigated by PI staining. The expression of BCL-2 family genes was analyzed by quantitative RT-PCR and expression of cyclins and COX-2 were done by RT-PCR.
  
  
  RESULTS
  GPE at 6.25-100 µg/ml reduced HT-29 cell viability with IC50 values of 69.49, 55.89, and 48.94 µg/ml at 24, 48, and 72 h, respectively. HT-29 apoptosis was induced by 18.23% at 100 µg/ml. Cells in S phase decreased by 5.22% and 13.28% at 50 and 100 µg/ml, respectively, causing G0/G1 (10.6% at 50 µg/ml) and G2/M (15.67% at 100 µg/ml) accumulation. GPE at 50 µg/ml downregulated cyclin A (11.46%), cyclin E (17.98%), BCL-2 (0.32-fold), and COX-2 (29.06%) expression with an increased BAK expression (1.79-fold).
  
  
  CONCLUSIONS
  GPE reduced HT-29 cell viability, inhibited cell proliferation, induced apoptosis, and arrested the cell cycle. Underlying mechanisms may involve decreases in COX-2, cyclin A, and cyclin E expression in addition to changes in BCL-2 family gene expression. Fundamental knowledge of GPE anticancer effects found in this study could lead to future use of this compound for colorectal cancer treatment.
authors.affiliation: Interdisciplinary Program of Pharmacology, Graduate School, Chulalongkorn University , Bangkok , Thailand .
authors.forename: Nattaporn
authors.initials: N
authors.lastname: Buranabunwong
authors.forename: Nijsiri
authors.initials: N
authors.lastname: Ruangrungsi
authors.forename: Chaisak
authors.initials: C
authors.lastname: Chansriniyom
authors.forename: Wacharee
authors.initials: W
authors.lastname: Limpanasithikul
mesh_terms: D000085:Acetates / Q000737:chemistry; D017209:Apoptosis / Q000187:drug effects*; D059447:Cell Cycle Checkpoints / Q000187:drug effects* / Q000235:genetics; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D051546:Cyclooxygenase 2 / Q000235:genetics*; D052246:Cyclooxygenase 2 Inhibitors / Q000302:isolation & purification / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D019254:Genes, bcl-2 / Q000187:drug effects*; D019073:HT29 Cells; D006801:Humans; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D060888:Real-Time Polymerase Chain Reaction; D027821:Rutaceae / Q000737:chemistry*
chemical_list: D000085:Acetates; D052246:Cyclooxygenase 2 Inhibitors; D010936:Plant Extracts; C007650:ethyl acetate; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human
keywords: Anticancer; arborinine; traditional herbal medicine