title: Cardanol isolated from Thai Apis mellifera propolis induces cell cycle arrest and apoptosis of BT-474 breast cancer cells via p21 upregulation.
abstract: BACKGROUND
  Cardanol was previously reported to be an antiproliferative compound purified from Thai Apis mellifera propolis. By morphology, it could induce the cell death to many cancer cell lines but not the control (non-transformed human foreskin fibroblast cell line, Hs27). Here, it was aimed to evaluate the molecular effects of cardanol on breast cancer derived cell line (BT-474).
  
  
  METHODS
  Morphological changes in BT-474 cells induced by cardanol compared to doxorubicin were evaluated by light microscopy, cytotoxicity by using the 3- (4, 5-dimethyl-thiazol-2-yl) 2, 5-diphenyl-tetrazolium bromide (MTT) assay, induction of cell cycle arrest and cell death by flow cytometric analysis of propidium iodide and annexin-V stained cells, and changes in the expression level of genes involved in the control of apoptosis and the cell cycle by quantitative reverse transcriptase-PCR (qRT-PCR) and western blot analyses.
  
  
  RESULTS
  It revealed that cardanol induced a time- and dose-dependent cytotoxicity along with cell shrinkage and detachment from substratum. Cardanol caused cell cycle arrest at the G1 subphase (as opposed to at the G2/M subphase seen with doxorubicin) and cell death by late apoptosis, with both late apoptosis (27.2 ± 1.1 %) and necrosis (25.4 ± 1.4 %) being found in cardanol treated cells after 72 h, compared to a lower proportion of apoptosis (4.3 ± 0.4 %) and higher proportion of necrosis (35.8 ± 13.0 %) induced by doxorubicin. Moreover, cardanol changed the transcript expression levels of genes involved in the control of apoptosis (increased DR5 and Bcl-2 expression and decreased Mcl-1, MADD and c-FLIPP) and cell division (increased p21 and E2FI and decreased cyclin D1, cyclin E, CDK4 and CDK2 expression), as well as increasing the level of p21 p-ERK, p-JNK and p-p38 and decreasing cyclin D. This accounts for the failure to progress from the G1 to the S subphase.
  
  
  CONCLUSIONS
  Cardanol is a potential chemotherapeutic agent for breast cancer.
authors.affiliation: Program in Biotechnology, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok, 10330, Thailand.
authors.forename: Sureerat
authors.initials: S
authors.lastname: Buahorm
authors.affiliation: Institute of Biotechnology and Genetic Engineering, Chulalongkorn University, 254 Phayathai Road, Bangkok, 10330, Thailand.
authors.forename: Songchan
authors.initials: S
authors.lastname: Puthong
authors.affiliation: Department of Microbiology, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok, 10330, Thailand.
authors.forename: Tanapat
authors.initials: T
authors.lastname: Palaga
authors.affiliation: Laboratory of Biochemistry, Chulabhorn Research Institute, Vipawadee Rangsit Highway, Bangkok, 10210, Thailand.
authors.forename: Kriengsak
authors.initials: K
authors.lastname: Lirdprapamongkol
authors.affiliation: Department of Chemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok, 10330, Thailand.
authors.forename: Preecha
authors.initials: P
authors.lastname: Phuwapraisirisan
authors.affiliation: Laboratory of Biochemistry, Chulabhorn Research Institute, Vipawadee Rangsit Highway, Bangkok, 10210, Thailand.
authors.forename: Jisnuson
authors.initials: J
authors.lastname: Svasti
authors.affiliation: Department of Biology, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Bangkok, 10330, Thailand. chanpen@sc.chula.ac.th.
authors.forename: Chanpen
authors.initials: C
authors.lastname: Chanchao
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000302:isolation & purification / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D001516:Bees / Q000737:chemistry*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism*; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics / Q000378:metabolism*; D004317:Doxorubicin / Q000494:pharmacology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D010636:Phenols / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D010636:Phenols; C038590:cardanol; D004317:Doxorubicin