title: Effects of triterpene derivatives from Maytenus rigida on VEGF-induced Kaposi's sarcoma cell proliferation.
abstract: Betulinic acid (BA) is a naturally occurring lupane-type triterpene which exhibits a variety of biological activities including potent cytotoxic properties. On the basis of the structural similarity to BA, two lupane derivatives namely lup-20(29)-ene-3beta,30-diol (1) and lup-20(29)-ene-3beta,28-diol (2), along with two friedelane derivatives, namely friedelan-3-one (3) and friedelan-3beta-ol (4), isolated from the Brazilian plant Maytenus rigida, have been evaluated for their anti-proliferative effect. Similarly to BA, compounds 1 and 3 at 1 microM concentration significantly inhibited the VEGF-induced Kaposi's sarcoma (KS) cell proliferation by 50%. In contrast, this effect was not found in control endothelial cells (EC). Moreover, compounds 1 and 3 showed a dose-dependent effect on the apoptotic cell death, as detected by FACS analysis and caspase-3 assay. Specifically, at 10 microM concentration, apoptosis was significantly induced (from 45% to 55% of hypodiploid cells vs control cells) and showed the same potency order observed for the anti-proliferative effect at 1 microM, i.e., compound 3>BA>compound 1. Taking into account the interest given rise by BA as anticancer agent, the comparable anti-proliferative activity shown by compounds 1 and 3 and BA, can give an impulse to further investigate lupane and friedelane derivatives as cytotoxic agents.
authors.affiliation: Dipartimento di Chimica, Università degli Studi di Salerno, via Ponte Don Melillo, Fisciano, Salerno, Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Martucciello
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Balestrieri
authors.forename: Francesca
authors.initials: F
authors.lastname: Felice
authors.forename: Charles dos Santos
authors.initials: Cdos S
authors.lastname: Estevam
authors.forename: Antonio Euzébio Goulart
authors.initials: AE
authors.lastname: Sant'Ana
authors.forename: Cosimo
authors.initials: C
authors.lastname: Pizza
authors.forename: Sonia
authors.initials: S
authors.lastname: Piacente
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity*; D017209:Apoptosis; D053148:Caspase 3 / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D006801:Humans; D029755:Maytenus / Q000737:chemistry*; D012514:Sarcoma, Kaposi / Q000188:drug therapy*; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity*; D042442:Vascular Endothelial Growth Factors / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; D014315:Triterpenes; D042442:Vascular Endothelial Growth Factors; D053148:Caspase 3