title: Differential signaling involved in Sutherlandia frutescens-induced cell death in MCF-7 and MCF-12A cells.
abstract: BACKGROUND
  The scientific study of natural products traditionally used in anticancer preparations has yielded several therapeutically relevant compounds. One of these traditional preparations with potentially beneficial properties is aqueous extracts of Sutherlandia frutescens, a shrub indigenous to the Western Cape region of South Africa. The aims of this study were to evaluate in vitro efficacy of these preparations on the MCF-7 breast adenocarcinoma and MCF-12A non-tumorigenic cell lines in terms of cell proliferation, cell morphology and possible induction of cell death.
  
  
  METHODS
  Crystal violet staining was used to evaluate cell proliferation, light-and fluorescence microscopy were used to investigate both intracellular and extracellular morphological features of apoptosis and autophagy (e.g. membrane blebbing, condensed chromatin and intracellular lysosomes), while flow cytometry quantified cell cycle changes and induction of apoptosis through analysis of the flip-flop translocation of phosphatidylserine.
  
  
  RESULTS
  Crystal violet staining showed a time- and dose specific response to aqueous Sutherlandia frutescens extracts, revealing exposure to 1mg/ml aqueous extract for 48h to be ideal for comparing the differential effects of Sutherlandia frutescens in the MCF-7 and MCF-12A cell lines. Microscopy showed distinct morphological changes with hallmarks of apoptosis being observed in both cell lines. Flow cytometry revealed a decrease in actively cycling cells in both cell lines, and a 4.36% increase in phosphatidylserine translocation in the MCF-7 cell line, indicative of apoptosis induction, while fluorescence microscopy showed evidence of the induction of autophagy.
  
  
  CONCLUSIONS
  Analyses revealed the carcinogenic MCF-7 cell line to be more susceptible to the cytostatic and cytotoxic effects of aqueous extracts of Sutherlandia frutescens when compared to the non-tumorigenic MCF-12A cell line, thus warranting further research into the exact cellular mechanisms involved and the possible synergistic activities of Sutherlandia frutescens ingredients.
authors.affiliation: Department of Physiology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
authors.forename: Chris
authors.initials: C
authors.lastname: Vorster
authors.forename: Andre
authors.initials: A
authors.lastname: Stander
authors.forename: Annie
authors.initials: A
authors.lastname: Joubert
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects*; D001343:Autophagy / Q000187:drug effects*; D001692:Biological Transport / Q000187:drug effects; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D002460:Cell Line; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D007887:Fabaceae; D005260:Female; D005840:Gentian Violet / Q000378:metabolism; D006801:Humans; D010718:Phosphatidylserines / Q000378:metabolism; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use*; D015398:Signal Transduction / Q000187:drug effects; D013019:South Africa
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D010718:Phosphatidylserines; D010936:Plant Extracts; D005840:Gentian Violet