ظافر صاحب جواد جواد

Abstract Resveratrol is widely promoted as a potential cancer chemopreventive agent, but a lack of information on the optimal dose prohibits rationally designed trials to assess efficacy. To challenge the assumption that "more is better," we compared the pharmacokinetics and activity of a dietary dose with an intake 200 times higher. The dose-response relationship for concentrations generated and the metabolite profile of [(14)C]-resveratrol in colorectal tissue of cancer patients helped us to define clinically achievable levels. In Apc(Min) mice (a model of colorectal carcinogenesis) that received a high-fat diet, the low resveratrol dose suppressed intestinal adenoma development more potently than did the higher dose. Efficacy correlated with activation of adenosine monophosphate-activated protein kinase (AMPK) and increased expression of the senescence marker p21. Nonlinear dose responses were observed for AMPK and mechanistic target of rapamycin (mTOR) signaling in mouse adenoma cells, culminating in autophagy and senescence. In human colorectal tissues exposed to low dietary concentrations of resveratrol ex vivo, we measured enhanced AMPK phosphorylation and autophagy. The expression of the cytoprotective NAD(P)H dehydrogenase, quinone 1 (NQO1) enzyme was also increased in tissues from cancer patients participating in our [(14)C]-resveratrol trial. These findings warrant a revision of developmental strategies for diet-derived agents designed to achieve cancer chemoprevention.

The present study aimed to assess the correlation between vascular endothelial growth factor (VEGF) overexpression and the grade, size, and recurrence of transitional cell carcinoma (TCC) in the south of Iraq, which includes regions that have been exposed to high levels of depleted uranium. The study also sought to evaluate whether there is any biomarker in the expression that could be correlated with the increased incidence of this type of cancer in the exposed areas. Samples of formalin-fixed and paraffin-embedded tissue from 54 patients (41 males and 13 females) with TCC and from 32 patients with benign bladder lesions (cystitis) used as controls were included in this study. The avidin-biotin complex method was used for immunohistochemical detection of VEGF. VEGF immunoexpression was positive in 77.77% of TCC but was not found in benign bladder lesions (cystitis) (P<0.05). VEGF immunostaining was positively correlated with grade, stage, and recurrence of TCC but the findings were not statistically significant (P>0.05). These findings support the role of VEGF in the carcinogenesis of TCC regarding evolution, behavior, and aggressiveness. Hence, VEGF could be considered as a poor prognostic parameter in bladder cancer. No positive correlation between immunohistochemical expression and the high incidence of TCC was detected (R=<0.3). The study further concludes that immunohistochemical expression of the VEGF gene in TCC bladder cancer does not differ from similar cancers found in other parts of the world where there has been no known exposure to depleted uranium.