title: Polyphenol rich botanicals used as food supplements interfere with EphA2-ephrinA1 system.
abstract: The Eph tyrosine kinase receptors and their ephrin ligands play a central role in several human cancers and their deregulated expression or function promotes tumorigenesis, inducing aggressive tumor phenotypes. Green tea extracts (GTE) have been recently found to inhibit Eph-kinase phosphorylation. In order to evaluate the potential contribution of edible and medicinal plants on EphA2-ephrinA1 modulation, 133 commercially available plant extracts used as food supplements, essential and fixed oils were screened with an ELISA-based binding assay. Nine plant extracts, rich of polyphenols, reversibly inhibited binding in a dose-dependent manner (IC₅₀ 0.83-24 μg/ml). Functional studies on PC3 prostate adenocarcinoma cells revealed that active extracts antagonized ephrinA1-Fc-induced EphA2-phosphorylation at non-cytotoxic concentrations (IC₅₀ 0.31-11.3 μg/ml) without interfering with EGF-induced EGFR activation, suggesting a specific effect. These findings could furnish an interesting starting point regarding the potential relationship between diet, edible plant secondary metabolites and Eph-ephrin system, suggesting their possible involvement in cancer development modulation.
authors: Dipartimento di Scienze Farmacologiche, Biologiche e Chimiche Applicate, Università di Parma, Viale G.P. Usberti 27a, 43124 Parma, Italy.
authors: Iftiin Hassan
authors: IH
authors: Mohamed
authors: Carmine
authors: C
authors: Giorgio
authors: Renato
authors: R
authors: Bruni
authors: Lisa
authors: L
authors: Flammini
authors: Elisabetta
authors: E
authors: Barocelli
authors: Damiano
authors: D
authors: Rossi
authors: Giuseppe
authors: G
authors: Domenichini
authors: Ferruccio
authors: F
authors: Poli
authors: Massimiliano
authors: M
authors: Tognolini
mesh_terms: D045744:Cell Line, Tumor; D019587:Dietary Supplements; D036382:Ephrin-A1 / Q000378:metabolism*; D006801:Humans; D008297:Male; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D010946:Plants, Medicinal / Q000737:chemistry*; D059808:Polyphenols / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D011471:Prostatic Neoplasms / Q000178:diet therapy / Q000378:metabolism*; D036104:Receptor, EphA2 / Q000378:metabolism*
chemical_list: D036382:Ephrin-A1; D010936:Plant Extracts; D059808:Polyphenols; D036104:Receptor, EphA2