title: Cytotoxicity of 15 Cameroonian medicinal plants against drug sensitive and multi-drug resistant cancer cells.
abstract: BACKGROUND
  Cameroonian medicinal plants are traditionally used to treat many ailments, including cancer and related diseases. Cancer is characterized as a condition with complex signs and symptoms. It has been recommended that ethnopharmacological usages such as immune and skin disorders, inflammatory, infectious, parasitic and viral diseases should be taken into account when selecting plants for anticancer screenings, since these reflect disease states bearing relevance to cancer or cancer-like symptoms.
  
  
  OBJECTIVE
  The present study aims at investigating 20 methanol extracts from 15 Cameroonian medicinal plants on a panel of human cancer cell lines, including various drug-resistant phenotypes. Possible modes of action of the of the most active plant were analyzed.
  
  
  METHODS
  Methanol extracts from different plant parts (leaves, bark, roots, fruits or whole plant) were evaluated for their cytotoxicity using resazurin reduction assay on a panel of nine sensitive and multi-drug resistant (MDR) cancer cell lines. Cell cycle, apoptosis, mitochondrial membrane potential (MMP), and reactive oxygen species (ROS) were measured by flow cytometry.
  
  
  RESULTS
  Prescreening of extracts at 80µg/mL showed that 6 extracts out of 20 inhibited more than 50% proliferation of leukemia CCRF-CEM cells; these include extracts from Anthocleista schweinfurthii fruits (ASF; 48.28%), Morus mesozygia bark (MMB; 42.76%), Nauclea latifolia bark (NLB; 38.75%), Tridesmostemon omphalocarpoides bark (TOB; 38.53%), Nauclea latifolia leaves (NLL; 35.17%) and Erythrina sigmoidea bark (ESB; 33.77%). Subsequent investigations revealed IC50 values below or around 20µg/mL for extracts from MMB, NLB, NLL and ESB towards sensitive CCRF-CEM cells and its resistant P-glycoprotein over-expressing subline CEM/ADR5000. The best extract, ESB also displayed IC50 values below 20µg/mL colon carcinoma HCT116 (p53(+/+)) cells with an IC50 value of 19.63µg/mL and it resistant p53 knockout subline HCT116 (p53(-)(/-)) with an IC50 value of 16.22µg/mL.
  
  
  CONCLUSIONS
  Erythrina sigmoidea, Anthocleista schweinfurthii, Morus mesozygia, Nauclea latifolia, Tridesmostemon omphalocarpoides used in African traditional medicine are good cytotoxic plants that can be exploited to develop phytomedicine to fight cancers including MDR phenotypes.
authors.affiliation: Department of Pharmaceutical Biology, Institute of Pharmacy and Biochemistry, University of Mainz, Staudinger Weg 5, 55128 Mainz, Germany; Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon. Electronic address: kuetevictor@yahoo.fr.
authors.forename: Victor
authors.initials: V
authors.lastname: Kuete
authors.affiliation: Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon.
authors.forename: Doriane E
authors.initials: DE
authors.lastname: Djeussi
authors.affiliation: Department of Biochemistry, Faculty of Science, University of Dschang, Dschang, Cameroon.
authors.forename: Armelle T
authors.initials: AT
authors.lastname: Mbaveng
authors.affiliation: Department of Pharmaceutical Biology, Institute of Pharmacy and Biochemistry, University of Mainz, Staudinger Weg 5, 55128 Mainz, Germany.
authors.forename: Maen
authors.initials: M
authors.lastname: Zeino
authors.affiliation: Department of Pharmaceutical Biology, Institute of Pharmacy and Biochemistry, University of Mainz, Staudinger Weg 5, 55128 Mainz, Germany. Electronic address: efferth@uni-mainz.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Efferth
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D002163:Cameroon; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D018432:Drug Resistance, Multiple / Q000187:drug effects*; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D006801:Humans; D019684:Magnoliopsida; D016488:Medicine, African Traditional; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D009369:Neoplasms / Q000188:drug therapy; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology*; D010946:Plants, Medicinal; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D010936:Plant Extracts; D017382:Reactive Oxygen Species
keywords: Apoptosis; Cameroon; Cytotoxicity; Erythrina sigmoidea; Medicinal plants