Wine polyphenols exert antineoplasic effect on androgen resistant PC-3 cell line through the inhibition of the transcriptional activity of COX-2 promoter mediated by NF-kβ.
OBJECTIVE
Mediterranean diet may play a role in the prevention of prostate cancer (PCa) development and progression. Cyclooxygenase-2 (COX-2) expression is associated with increased cellular proliferation, prevents apoptosis and favors tumor invasion. We intend to clarify whether resveratrol and other polyphenols effectively inhibit COX-2 activity and induce apoptosis in hormone-resistant PC-3 cell line.


METHODS
PC-3 cells were cultured and treated with different concentrations of gallic acid, tannic acid, quercetin, and resveratrol in presence of phorbol myristate acetate (PMA; 50 μg/ml) that induces COX-2 expression. Total RNA was extracted and COX-2 expression was analyzed by relative quantification real-time PCR (ΔΔCt method). COX-2 activity was determined by PGE-2 detection using ELISA. Caspase 3/7 luminescence assay was used to disclose apoptosis. Transitory transfection with short human COX-2 (phPES2 -327/+59) and p5xNF-kβ-Luc plasmids determined COX-2 promoter activity and specifically that dependant of NF-kβ.


RESULTS
COX-2 expression was not modified in media devoid of PMA. However, under PMA induction tannic acid (2.08 ±.21), gallic acid (2.46 ±.16), quercetin (1.78 ±.14) and resveratrol (1.15 ±.16) significantly inhibited COX-2 mRNA with respect to control (3.14 ±.07), what means a 34%, 23%, 46% and 61% reduction, respectively. The inhibition in the levels of PGE-2 followed a similar pattern. All compounds studied induced apoptosis at 48 h, although at a different rate. PMA caused a rise in activity 7.4 ±.23 times phPES2 -327/+59 and 2.0 ±.1 times p5xNF-kβ-Luc at 6h compared to basal. Resveratrol suppressed these effects 17.1 ±.21 and 32.4 ±.18 times, respectively. Similarly, but to a lesser extent, the rest of evaluated polyphenols diminished PMA inductor effect on the activity of both promoters.


CONCLUSIONS
Polyphenols inhibit transcriptional activity of COX-2 promoter mediated by NF-kβ. This effect could explain, at least in part, the induction of apoptosis in vitro by these substances in castration resistant PCa.
Unidad de Investigación, Fundación para la Investigación Biomédica del Hospital Universitario de Getafe, Madrid, España.
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Ferruelo
Servicio de Urología, Hospital Universitario de Getafe, Departamento Clínico, Facultad de Ciencias Biomédicas, Universidad Europea de Madrid, Madrid, España.
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de Las Heras
Servicio de Urología, Hospital Universitario de Getafe, Departamento Clínico, Facultad de Ciencias Biomédicas, Universidad Europea de Madrid, Madrid, España.
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Redondo
Servicio de Urología, Hospital Universitario de Getafe, Departamento Clínico, Facultad de Ciencias Biomédicas, Universidad Europea de Madrid, Madrid, España.
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Ramón de Fata
Servicio de Urología, Hospital Universitario de Getafe, Departamento Clínico, Facultad de Ciencias Biomédicas, Universidad Europea de Madrid, Madrid, España.
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Romero
Servicio de Urología, Hospital Universitario de Getafe, Departamento Clínico, Facultad de Ciencias Biomédicas, Universidad Europea de Madrid, Madrid, España. Electronic address: javier.angulo@salud.madrid.org.
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Angulo
D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D045744:Cell Line, Tumor / Q000187:drug effects; D051546:Cyclooxygenase 2 / Q000235:genetics* / Q000502:physiology; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology*; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D008297:Male; D016328:NF-kappa B / Q000502:physiology*; D059808:Polyphenols / Q000494:pharmacology*; D011401:Promoter Regions, Genetic / Q000187:drug effects*; D064129:Prostatic Neoplasms, Castration-Resistant / Q000473:pathology*; D000077185:Resveratrol; D013267:Stilbenes / Q000494:pharmacology*; D015533:Transcriptional Activation / Q000187:drug effects*; D014920:Wine
D000970:Antineoplastic Agents; D052246:Cyclooxygenase 2 Inhibitors; D016328:NF-kappa B; D059808:Polyphenols; D013267:Stilbenes; D051546:Cyclooxygenase 2; D000077185:Resveratrol
COX-2; Castrate-resistant prostate cancer; Cáncer de próstata resistente a castración; Línea celular PC-3; NF-kβ; PC-3 cell line; Polifenoles; Polyphenols; Resveratrol