Solar UV radiation, in particular its UVB component, is the primary cause of many adverse biological effects, the most damaging of which is skin cancer. Here, we assessed the photochemopreventive effect of delphinidin, a major anthocyanidin present in many pigmented fruits and vegetables, on UVB-mediated responses in human immortalized HaCaT keratinocytes and SKH-1 hairless mouse skin. We found that pretreatment of cells with delphinidin (1-20 microM for 24 hours) protected against UVB (15-30 mJ/cm2, 24 hours)-mediated (i) decrease in cell viability and (ii) induction of apoptosis. Furthermore, we found that pretreatment of HaCaT cells with delphinidin inhibited UVB-mediated (i) increase in lipid peroxidation; (ii) formation of 8-hydroxy-2'-deoxyguanosine (8-OHdG); (iii) decrease in proliferating cell nuclear antigen expression; (iv) increase in poly(ADP-ribose) polymerase cleavage; (v) activation of caspases; (vi) increase in Bax; (vii) decrease in Bcl-2; (viii) upregulation of Bid and Bak; and (ix) downregulation of Bcl-xL. Topical application of delphinidin (1 mg/0.1 ml DMSO/mouse) to SKH-1 hairless mouse skin inhibited UVB-mediated apoptosis and markers of DNA damage such as cyclobutane pyrimidine dimers and 8-OHdG. Taken together our results suggest that treatment of HaCaT cells and mouse skin with delphinidin inhibited UVB-mediated oxidative stress and reduced DNA damage, thereby protecting the cells from UVB-induced apoptosis.
Androgen receptor (AR)-mediated signaling plays an important role in the development and progression of prostate cancer (PCa). Hormonal therapies, mainly with combinations of antiandrogens and androgen deprivation, are the mainstay treatment for advanced disease. However, emergence of androgen resistance largely due to inefficient antihormone action limits their therapeutic usefulness. Here, we report that fisetin, a novel dietary flavonoid, acts as a novel AR ligand by competing with the high-affinity androgen to interact with the ligand binding domain of AR. We show that this physical interaction results in substantial decrease in AR stability and decrease in amino-terminal/carboxyl-terminal (N-C) interaction of AR. This results in blunting of AR-mediated transactivation of target genes including prostate-specific antigen (PSA). In addition, treatment of LNCaP cells with fisetin decreased AR protein levels, in part, by decreasing its promoter activity and by accelerating its degradation. Fisetin also synergized with Casodex in inducing apoptosis in LNCaP cells. Treatment with fisetin in athymic nude mice implanted with AR-positive CWR22RU1 human PCa cells resulted in inhibition of tumor growth and reduction in serum PSA levels. These data identify fisetin as an inhibitor of AR signaling axis and suggest that it could be a useful chemopreventive and chemotherapeutic agent to delay progression of PCa. [Cancer Res 2008;68(20):8555-63]
Solar ultraviolet (UV) radiation, particularly its UVB (290-320 nm) component, is the primary cause of many adverse biological effects including photoaging and skin cancer. UVB radiation causes DNA damage, protein oxidation and induces matrix metalloproteinases (MMPs). Photochemoprevention via the use of botanical antioxidants in affording protection to human skin against UVB damage is receiving increasing attention. Pomegranate, from the tree Punica granatum contains anthocyanins and hydrolyzable tannins and possesses strong anti-oxidant and anti-tumor promoting properties. In this study, we determined the effect of pomegranate derived products POMx juice, POMx extract and pomegranate oil (POMo) against UVB-mediated damage using reconstituted human skin (EpiDerm™ FT-200). EpiDerm was treated with POMx juice (1-2 μl/0.1 ml/well), POMx extract (5-10 μg/0.1 ml/well), and POMo (1-2 μl/0.1 ml/well) for 1 h prior to UVB (60 mJ/cm 2 ) irradiation and was harvested 12 h post-UVB to assess protein oxidation, markers of DNA damage and photoaging by western blot analysis and immunohistochemistry. Pretreatment of Epiderm with pomegranate derived products resulted in inhibition of UVBinduced (i) cyclobutane pyrimidine dimers, (ii) 8-dihydro-2′-deoxyguanosine, (iii) protein oxidation, and (iv) PCNA protein expression. We also found that pretreatment of Epiderm with pomegranate derived products resulted in inhibition of UVB-induced (i) collagenase (MMP-1), (ii) gelatinase (MMP-2, MMP-9), (iii) stromelysin (MMP-3), (iv) marilysin (MMP-7), (v) elastase (MMP-12), and (vi) tropoelastin. Gelatin zymography revealed that pomegranate derived products inhibited UVB-induced MMP-2 and MMP-9 activities. Pomegranate derived products also caused a decrease in UVB-induced protein expression of c-Fos and phosphorylation of c-Jun. Collectively, these results suggest that all three pomegranate derived products may be useful against UVB-induced damage to human skin.
To provide new information on adverse health outcomes (AHOs) in testicular cancer survivors (TCSs) after four cycles of etoposide and cisplatin (EPX4) or three or four cycles of bleomycin, etoposide, cisplatin (BEPX3/BEPX4). MethodsNine hundred fifty-two TCSs . 1 year postchemotherapy underwent physical examination and completed a questionnaire. Multinomial logistic regression estimated AHOs odds ratios (ORs) in relation to age, cumulative cisplatin and/or bleomycin dose, time since chemotherapy, sociodemographic factors, and health behaviors. ResultsMedian age at evaluation was 37 years; median time since chemotherapy was 4.3 years. Chemotherapy consisted largely of BEPX3 (38.2%), EPX4 (30.9%), and BEPX4 (17.9%). None, one to two, three to four, or five or more AHOs were reported by 20.4%, 42.0%, 25.1%, and 12.5% of TCSs, respectively. Median number after EPX4 or BEPX3 was two (range, zero to nine and zero to 11, respectively; P . .05) and two (range, zero to 10) after BEPX4. When comparing individual AHOs for EPX4 versus BEPX3, Raynaud phenomenon (11.6% v 21.4%; P , .01), peripheral neuropathy (29.2% v 21.4%; P = .02), and obesity (25.5% v 33.0%; P = .04) differed. Larger cumulative bleomycin doses (OR, 1.44 per 90,000 IU) were significantly associated with five or more AHOs. Increasing age was a significant risk factor for one to two, three to four, or five or more AHOs versus zero AHOs (OR, 1.22, 1.50, and 1.87 per 5 years, respectively; P , .01); vigorous physical activity was protective (OR, 0.62, 0.51, and 0.41, respectively; P , .05). Significant risk factors for three to four and five or more AHOs included current (OR, 3.05 and 3.73) or former (OR, 1.61 and 1.76) smoking (P , .05). Self-reported health was excellent/very good in 59.9% of TCSs but decreased as AHOs increased (P , .001). ConclusionNumbers of AHOs after EPX4 or BEPX3 appear similar, with median follow-up of 4.3 years. A healthy lifestyle was associated with reduced number of AHOs.
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