Deciphering the Molecular Mechanism Underlying the Inhibitory Efficacy of Taiwanese Local Pomegranate Peels against Urinary Bladder Urothelial Carcinoma.

Pomegranate (Punica granatum L.) fruit has been demonstrated to have the inhibitory activities to various tumors. In this study, we try to uncover the molecular mechanism underlying the inhibitory capability of Taiwanese local pomegranate fruit to urinary bladder urothelial carcinoma. The results collected from the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay indicated that the ethanol extract of pomegranate peel exhibited better inhibitory activity to human urinary bladder urothelial carcinoma T24 and J82 cells than that of pulp. Furthermore, the ethylacetate layer of peel ethanol extract was observed to have the best inhibitory activity against urinary bladder urothelial carcinoma cells. One of the eight fractions (PEPE2 fraction) collected from the ethylacetate layer with Diaion HP-20 column chromatography demonstrated the highest inhibitory activity in urinary bladder urothelial carcinoma cells. The results of the flow cytometry and apoptotic pathway studies suggested that the inhibitory activity of PEPE2 fraction were attributed to the UBUC cell apoptosis. To confirm the above results, our results of xenograft-induced bladder tumor in nude mice showed that the oral consumption of the ethylacetate layer (2, 5, 10 and 100 mg/kg) could decrease the volume and weight of T24 tumors and caused the apoptosis in the xenografted tumors, which was observed by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling assay. This study provided the likelihood that the traditionally non-edible pomegranate peel waste is re-utilized to make an affordable and promising chemopreventive product to prevent UBUC incidence or recurrence.

Suppression of urinary bladder urothelial carcinoma cell by the ethanol extract of pomegranate fruit through cell cycle arrest and apoptosis.

BACKGROUND: Pomegranate possesses many medicinal properties such as antioxidant, anti-inflammation and antitumor. It has been extensively used as a folk medicine by many cultures. Pomegranate fruit has been shown to have the inhibitory efficacy against prostate cancer and lung cancer in vitro and in vivo. It can be exploited in chemoprevention and chemotherapy of prostate cancer. In this study we examined the anti-cancer efficacy of pomegranate fruit grown in Taiwan against urinary bladder urothelial carcinoma (UBUC) and its mechanism of action. METHODS: Edible portion of Taiwanese pomegranate was extracted using ethanol and the anti-cancer effectiveness of ethanol extract was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Flow cytometry and western immunoblotting were exploited to uncover the molecular pathways underlying anti-UBUC activity of Taiwanese pomegranate ethanol extract. RESULTS: This study demonstrated that Taiwanese pomegranate fruit ethanol extract (PEE) could effectively restrict the proliferation of UBUC T24 and J82 cells. Cell cycle analyses indicated that the S phase arrest induced by PEE treatment might be caused by an increase in cyclin A protein level and a decrease in the expression of cyclin-dependent kinase 1. The results of western immunoblotting demonstrated that PEE treatment could not only evoke the activation of pro-caspase-3, -8,-9 but also increase Bax/Bcl-2 ratio in T24 cells. The above observations implicated that PEE administration might trigger the apoptosis in T24 cells through death receptor signaling and mitochondrial damage pathway. Besides we found that PEE exposure to T24 cells could provoke intensive activation of procaspase-12 and enhance the expressions of CHOP and Bip, endoplasmic reticulum (ER) stress marker, suggesting that ER stress might be the cardinal apoptotic mechanism of PEE-induced inhibition of bladder cancer cell. CONCLUSIONS: The analytical results of this study help to provide insight into the molecular mechanism of induced bladder cancer cell apoptosis by pomegranate and to develop novel mechanism-based chemopreventive strategy for bladder cancer.

Proteomic exploration of the impacts of pomegranate fruit juice on the global gene expression of prostate cancer cell.

Prostate cancer has been known to be the second highest cause of death in cancer among men. Pomegranate is rich in polyphenols with the potent antioxidant activity and inhibits cell proliferation, invasion, and promotes apoptosis in various cancer cells. This study demonstrated that pomegranate fruit juice could effectively hinder the proliferation of human prostate cancer DU145 cell. The results of apoptotic analyses implicated that fruit juice might trigger the apoptosis in DU145 cells via death receptor signaling and mitochondrial damage pathway. In this study, we exploited 2DE-based proteomics to compare nine pairs of the proteome maps collected from untreated and treated DU145 cells to identify the differentially expressed proteins. Comparative proteomics indicated that 11 proteins were deregulated in affected DU145 cells with three upregulated and eight downregulated proteins. These dys-regulated proteins participated in cytoskeletal functions, antiapoptosis, proteasome activity, NF-κB signaling, cancer cell proliferation, invasion, and angiogenesis. Western immunoblotting were implemented to confirm the deregulated proteins and the downstream signaling proteins. The analytical results of this study help to provide insight into the molecular mechanism of inducing prostate cancer cell apoptosis by pomegranate fruit juice and to develop a novel mechanism-based chemopreventive strategy for prostate cancer.

Apoptotic effects of a high performance liquid chromatography (HPLC) fraction of Antrodia camphorata mycelia are mediated by down-regulation of the expressions of four tumor-related genes in human non-small cell lung carcinoma A549 cell.

AIM OF THE STUDY: Antrodia camphorata (niu-chang-chih) is a fungus native to Taiwan which is believed to be effective in preventing diseases. Recent reports demonstrate that Antrodia camphorata products induce the apoptosis of various kinds of tumor cells. In this study we determined the inhibitory effects of alcohol extract and individual fractions of alcohol extract on the proliferation of human non-small cell lung carcinoma A549 cell and clarified the mechanism underlying the anti-cancer activities. MATERIALS AND METHODS: Alcohol extracts of Antrodia camphorata mycelia were prepared by the serial extraction with the solvents with increasing polarity and fractionated using HPLC. Cell viability was determined by MTT assay. Apoptosis detection was carried out by subG(1) analysis and annexin V/propidium iodide staining using flow cytometry. The impacts of HPLC fractions on the expression levels of apoptosis- and cancer-related proteins were evaluated by western blotting. RESULTS: Three HPLC fractions, fractions 5-7, had robust inhibition of human A549 cells and among them fraction 6 (Fr-6) possessed the most potent effectiveness. Apoptotic assay showed that Fr-6-induced human A549 cell apoptosis by triggering the mitochondrial pathway and endothelium reticulum (ER) stress. Immunoblotting results demonstrated that Fr-6 possibly activated ER stress by lowering the expression level of calpain 1/2 small subunit and Fr-6-mediated decrease in cell proliferation might attribute to the suppressive effect on the Erk 1/2 pathway, which arose from Fr-6-derived low galectin-1 expression. Furthermore Fr-6 could diminish Rho GDP dissociation inhibitor alpha (RhoGDI-alpha) expression and subsequently activated c-Jun NH(2)-terminal kinase (JNK) pathway, which is linked to cell apoptosis. Fr-6 also could decrease the production level of eukaryotic translation initiation factor 5A, which is a potential cancer intervention target. CONCLUSION: These results suggested that the anti-cancer activity of Antrodia camphorata might be due to multiple active metabolites, which work together to induce cell apoptosis via various pathways.