title: Cytotoxic activity of Brazilian Cerrado plants used in traditional medicine against cancer cell lines.
abstract: The search for new anti-cancer drugs is one of the most prominent research areas of natural products. Numerous active compounds isolated from Brazilian Cerrado plant species have been studied with promising results.
  
  
  OBJECTIVE
  To investigate the cytotoxic potential of 412 extracts from Brazilian Cerrado plants used in traditional medicine belonging to 21 families against tumor cell lines in culture.
  
  
  METHODS
  Maceration of 50 plant species resulted in 412 hexane, dichloromethane, ethanol and hydroalcohol extracts. The cytotoxicity of the extracts was tested against human colon carcinoma (HCT-8), melanoma (MDA-MB-435), and brain (SF-295) tumor cell lines, using the thiazolyl blue test (MTT) assay. Bioassay-guided fractionation was performed for one active extract.
  
  
  CONCLUSIONS
  Twenty-eight of the 412 tested extracts demonstrated a substantial antiproliferative effect, at least 85% inhibition of cell proliferation at 50 microg/mL against one or more cell lines. Those extracts are obtained from different parts of Anacardiaceae, Annonaceae, Apocynaceae, Clusiaceae, Flacourtiaceae, Sapindaceae, Sapotaceae, Simaroubaceae and Zingiberaceae. Complete dose-response curves were generated and IC(50) values were calculated for these active extracts against four cell lines HCT-8, MDA-MB-435, SF-295 and HL-60 (leukemia), and their direct cytotoxic effects were determined. In summary, 14 extracts of 13 species showed toxicity in all tested tumor cell lines, with IC(50) values ranging from 0.1 to 19.1 microg/mL. The strongest cytotoxic activity was found for the hexane extract of Casearia sylvestris var. lingua stem bark, with an IC(50) of 0.1 microg/mL for HCT-8, 0.9 microg/mL for SF-295, 1.2 microg/mL for MDA-MB-435, and 1.3 microg/mL for HL-60, and Simarouba versicolor root bark, with an IC(50) of 0.5 microg/mL for HCT-8, 0.7 microg/mL for SF-295, 1.5 microg/mL for MDA-MB-435, 1.1 microg/mL for HL-60. Bioassay-guided fractionation of the last extract led to the isolation of glaucarubinone, which showed pronounced activity against the four cell lines studied. Further studies of the active extracts are necessary for chemical characterization of the active compounds and more extensive biological evaluations.
authors.affiliation: Laboratório de Farmacognosia, Universidade de Brasília, Brasília, Brazil.
authors.forename: Mariana Laundry
authors.initials: ML
authors.lastname: de Mesquita
authors.forename: José Elias
authors.initials: JE
authors.lastname: de Paula
authors.forename: Cláudia
authors.initials: C
authors.lastname: Pessoa
authors.forename: Manoel Odorico
authors.initials: MO
authors.lastname: de Moraes
authors.forename: Letícia Veras
authors.initials: LV
authors.lastname: Costa-Lotufo
authors.forename: Raphael
authors.initials: R
authors.lastname: Grougnet
authors.forename: Sylvie
authors.initials: S
authors.lastname: Michel
authors.forename: François
authors.initials: F
authors.lastname: Tillequin
authors.forename: Laila Salmen
authors.initials: LS
authors.lastname: Espindola
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology / Q000627:therapeutic use*; D001938:Brazil; D037821:Casearia; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D004354:Drug Screening Assays, Antitumor; D017753:Ecosystem; D005900:Glaucarubin / Q000031:analogs & derivatives / Q000302:isolation & purification / Q000494:pharmacology / Q000627:therapeutic use; D006801:Humans; D020128:Inhibitory Concentration 50; D019684:Magnoliopsida / Q000737:chemistry*; D008519:Medicine, Traditional; D009369:Neoplasms / Q000188:drug therapy*; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use*; D018514:Plant Structures; D010946:Plants, Medicinal / Q000737:chemistry*; D032272:Simarouba
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D010936:Plant Extracts; C015235:glaucarubinone; D005900:Glaucarubin