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Background: Eicosapentaenoic acid (EPA) suppresses the proliferation of cell lines derived from colon, pancreatic, breast and other cancers. Few reports have described the effect of EPA on esophageal cancer cell lines., Materials and Methods: We investigated the effect of EPA on the proliferation of the esophageal squamous cell carcinoma cell lines TE11 and KYSE180 with a WST-1 assay. Apoptosis was evaluated with a DNA fragmentation assay. Levels of apoptosis-related proteins (caspase-3, -7, -9 and poly (ADP-ribose) polymerase (PARP)) and cleaved caspase-3, -7, -9 and PARP were evaluated by western blot analysis., Results: After exposure to EPA for 24 h, KYSE180 and TE11 cell proliferation was suppressed in a dose-dependent manner (p<0.05). In addition, caspase -3, -7, -9 and PARP were activated. EPA (0.1 μM, 1 μM, 10 μM) induced apoptosis in a dose-dependent manner, as detected by the DNA fragmentation assay., Conclusion: EPA shows potential as a new treatment for esophageal cancer., (Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)

Aim: The study of the anticancer effects of destruxin B (DB) is rare and its anticancer mechanism remains unknown. The aim of this study was to test the in vitro and in vivo anticancer effects of DB, on human HT-29 colorectal cancer (CRC)., Materials and Methods: DB was isolated and characterized by high pressure liquid chromatography, electrospray ionization mass spectrometry and (1)H-nuclear magnetic resonance spectroscopy. (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to assess the effects of DB on HT-29 cells in vitro. The anticancer effects of DB were investigated in a murine xenograft model of human colon cancer., Results: A significant inhibition of cell viability was observed with DB treatment in time- and dose-dependent manners. DB administered subcutaneously daily at 0.6-15 mg/kg was proven to be safe and effective in inhibiting the growth of CRC cells. Expression of Bax, cleaved poly (ADP-ribose) polymerase and active caspase-3 were observed with DB treatment and the increase in tumor volumes of treated groups were significantly (p<0.05) lower than those of the mock-treated group., Conclusion: DB has potential as a new therapeutic agent against human CRC.

Aim: To investigate the phosphatidylinositol 3-kinase (PI3K)-Akt and extracellular signal regulated protein kinase (ERK) activation by chemotherapy, and the relationship between the activation of them and patient outcomes. The effect of chemotherapy on the cell proliferation and apoptosis markers and their role in the biology of ovarian cancer were also investigated., Materials and Methods: This study was carried out in a series of 10 ovarian (or tubal) cancer patients whose specimens were obtained before and after chemotherapy. PI3K-Akt and ERK activation were evaluated by immunohistochemical staining for phosphorylated Akt and ERK. Their correlation with patient outcome was investigated by survival curves using the Kaplan-Meier method. Cell proliferation was evaluated by Ki-67 expression using immunofluorescent staining. Apoptosis was examined by caspase-3 and cleaved Poly ADP ribose polymerase (PARP) using immunofluorescent staining., Results: An increase in Akt and ERK phosphorylation after chemotherapy was observed in 5 and 8 patients, respectively out of 10 patients examined. Akt and ERK activation by chemotherapy were associated with a favorable overall survival. In almost all patients, Ki-67 expression was initially high and largely decreased after chemotherapy. An increase in apoptotic marker expression was observed in almost all patients exposed to chemotherapy., Conclusion: Our findings suggest that Akt and ERK activation by chemotherapy may be associated with favorable prognosis.

Rocaglaol is a cytotoxic cyclopenta[b]benzofuran isolated from the bark of Aglaia crassinervia. It exhibited in vitro cytotoxic activity against Lu1, LNCaP and MCF-7 cells with ED50 values of 13.8, 23.0 and 9.2 nM, respectively. DAPI staining indicated that LNCaP cells treated with rocaglaol underwent apoptosis. In order to determine whether rocaglaol-induced apoptosis is mediated by the mitochondrial pathway, apoptosis-related mitochondrial-associated proteins were studied. Rocaglaol treatment induced Bax expression through 12 to 72 h of exposure, while Bcl-xl expression was slightly decreased through 48 h, and decreased more significantly by 72 h. Cleaved caspase-9 expression was detected at 72 h, and cleaved caspase-7 was increased through 48 to 72 h. Consequently, the large fragment (89 kDa) of PARP resulting from caspase cleavage was detected at 12, 24 and 48 h, and especially at 72 h. Cleaved PARP expression was also detected at 72 h. Since rocaglaol caused dose-dependent G2/M phase arrest of LNCaP cells as indicated by flow cytometric analysis, the protein levels of cell cycle-related genes were measured. Rocaglaol treatment (230 nM) did not change cyclin B after 24- to 60-h treatment. The expression of cdc2 was not changed and phospho-cdc2 (Tyr 15) increased after 36-, 48- and 60-h treatment. In addition, protein phosphatase Cdc25C, which functions as a mitotic activator by dephosphorylation of Cdc2, decreased in a time-dependent manner after rocaglaol treatment. Taken together, these results suggest that rocaglaol is a potent anticancer drug that induces apoptosis of LNCaP cells through the mitochondrial pathway and its G2/M-phase cell cycle arrest is associated with the down-regulation of Cdc25C and the dephosphorylation of Cdc2.