RESUMEN
Adenomatous polyps are precancerous lesions associated with a higher risk of colorectal cancer (CRC). Curcumin and anthocyanins have shown promising CRC-preventive activity in preclinical and epidemiological studies. The objective of this window-of-opportunity, proof-of principle trial was to evaluate the effect of curcumin combined with anthocyanin supplements on tissue biomarkers of colorectal adenomatous polyps. Eligible patients received either anthocyanin and curcumin supplementation or related matching placebo for 4-6 weeks before polyp removal. Adenomatous polyps and adjacent tissue biopsies were collected at baseline and after supplementation for immunohistochemical assessment of ß-catenin, NF-kappa B (NF-κB), Ki-67, P53, and dysplasia. No differences were observed in baseline biomarker expression between normal and dysplastic tissues. The combination of anthocyanins and curcumin resulted in a significant borderline reduction of NF-κB immunohistochemistry (IHC) expression in adenoma tissue (geometric mean ratio (GMR): 0.72; 95% confidence interval (CI): 0.51-1.00; p-value: 0.05) and a trend to a reduction of Ki-67 (GMR: 0.73; 95% CI: 0.50-1.08; p-value: 0.11). No significant modulation of biomarkers in normal adjacent mucosa was observed. We concluded that the combined supplementation of anthocyanins and curcumin seems to lead to a potentially favorable modulation of tissue biomarkers of inflammation and proliferation in colon adenomas.
Asunto(s)
Pólipos Adenomatosos/prevención & control , Antocianinas/farmacología , Neoplasias Colorrectales/prevención & control , Curcumina/farmacología , Suplementos Dietéticos , Pólipos Adenomatosos/genética , Pólipos Adenomatosos/metabolismo , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Antígeno Ki-67/genética , Masculino , Persona de Mediana Edad , FN-kappa B/genética , Proteína p53 Supresora de Tumor/genéticaRESUMEN
Human malignant pleural mesothelioma (MPM) is a dreadful disease and there is still no standard therapy available for a consistent therapeutic approach. This research is aimed at the evaluation of the potential therapeutic effect of a specific nicotinic receptor (nAChR) antagonist, namely alpha-Cobratoxin (alpha-CbT). Its effectiveness was tested in mesothelioma cell lines and in primary mesothelioma cells in vitro, as well as in vivo, in orthotopically xenotransplanted NOD/SCID mice. Cells showed alpha7-nAChR expression and their growth was significantly inhibited by alpha-CbT. Severe induction of apoptosis was observed after exposure to alpha-CbT [IC(80-90)]. Apoptosis was characterised by: change in mitochondrial potential, caspase-3 cleavage, down-regulation of mRNA and protein for survivin, XIAP, IAP1, IAP2 and Bcl-XL, inhibition by caspase-3 inhibitor. In vivo, the alpha-CbT acute LD(50) was 0.15 mg/kg. The LD(100) [0.24 mg/kg] induced fatal respiratory failure and massive kidney necrosis. Phase II experiments with 0.12 ng/kg alpha-CbT (1/1000 of LD(10)) were done in 53 xenotransplanted mice, inhibiting tumour development as confirmed by chest X-ray examinations, autopsy and microscopical findings. The growth of human proliferating T lymphocytes and of mesothelial cells in primary culture was not affected by alpha-CbT. Non-immunogenic derivatives of the alpha-CbT molecule need to be developed for possible human use.