title: In vitro antitumour activity of orsellinates.
abstract: Lichen phenolic compounds exhibit antioxidant, antimicrobial, antiproliferative, and cytotoxic activities. The purpose of this study was to evaluate the anticancer activity of lecanoric acid, a secondary metabolite of the lichen Parmotrema tinctorum, and its derivatives, orsellinates, obtained by structural modification. A cytotoxicity assay was carried out in vitro with sulforhodamine B (SRB) using HEp-2 larynx carcinoma, MCF7 breast carcinoma, 786-0 kidney carcinoma, and B16-F10 murine melanoma cell lines, in addition to a normal (Vero) cell line in order to calculate the selectivity index of the compounds. n-Butyl orsellinate was the most active compound, with IC50 values (the concentration that inhibits 50% of growth) ranging from 7.2 to 14.0 microg/mL, against all the cell lines tested. The compound was more active (IC50 = 11.4 microg/mL) against B16-F10 cells than was cisplatin (12.5 microg/mL). Conversely, lecanoric acid and methyl orsellinate were less active against all cell lines, having an IC50 value higher than 50 microg/mL. Ethyl orsellinate was more active against HEp-2 than against MCF7, 786-0, or B16-F10 cells. The same pattern was observed for n-propyl and n-butyl orsellinates. n-Pentyl orsellinate was less active than n-propyl or n-butyl orsellinates against HEp-2 cells. The orsellinate activity increased with chain elongation (from methyl to n-butyl), a likely consequence of an increase in lipophilicity. The results revealed that the structural modification of lecanoric acid increases the cytotoxic activity of the derivatives tested.
authors.affiliation: Laboratório de Biologia Molecular e Culturas Celulares, Departamento de Farmácia-Bioquímica, Universidade Federal de Mato Grosso do Sul (UFMS), Caixa Postal 549, Campo Grande, MS 79070-900, Brazil.
authors.forename: Danielle
authors.initials: D
authors.lastname: Bogo
authors.forename: Maria Fatima Cepa
authors.initials: MF
authors.lastname: de Matos
authors.forename: Neli Kika
authors.initials: NK
authors.lastname: Honda
authors.forename: Elenir Curi
authors.initials: EC
authors.lastname: Pontes
authors.forename: Patricia Midori
authors.initials: PM
authors.lastname: Oguma
authors.forename: Evelyn Cristina Silva
authors.initials: EC
authors.lastname: da Santos
authors.forename: João Ernesto
authors.initials: JE
authors.lastname: de Carvalho
authors.forename: Auro
authors.initials: A
authors.lastname: Nomizo
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy; D002448:Cell Adhesion; D045744:Cell Line, Tumor; D002522:Chlorocebus aethiops; D005260:Female; D049691:History, Medieval; D006801:Humans; D008546:Melanoma, Experimental / Q000188:drug therapy; D008958:Models, Molecular; D012118:Resorcinols / Q000737:chemistry / Q000627:therapeutic use*; D012459:Salicylates / Q000737:chemistry / Q000627:therapeutic use*; D014709:Vero Cells / Q000187:drug effects*
chemical_list: D000970:Antineoplastic Agents; D012118:Resorcinols; D012459:Salicylates; C501612:orsellinic acid; C008263:lecanoric acid