The Mechanism of the Synergistic Anticancer Effect of CDDP and EPA in the TE1 Cell Line.

BACKGROUND/AIM: Eicosapentaenoic acid (EPA) is an unsaturated fatty acid with various bioactivities, including antitumor effects. We previously reported a synergistic antitumor effect of cisplatin (CDDP) and EPA. Here, we examined the underlying mechanism. MATERIALS AND METHODS: The human oesophageal cancer cell line TE-1 was treated with the combination of EPA and CDDP. Nuclear translocation of NF-κB, a transcription factor involved in cytokine production, was detected by immunohistochemistry. IL-6 levels were measured by ELISA. Apoptosis and cell cycle distribution were evaluated by flow cytometry. RESULTS: Nuclear translocation of NF-κB in TE-1 cells was synergistically decreased by CDDP and EPA. IL-6 production was increased following treatment with CDDP, but treatment with EPA decreased IL-6 levels. Apoptosis was synergistically induced by CDDP and EPA. A G2/M cell cycle arrest was observed with the combination of CDDP and 150 µM EPA, and S phase arrest with the combination of CDDP and 100 µM EPA. CONCLUSION: The combination of CDDP and EPA synergistically suppresses NF-κB nuclear translocation and increases apoptosis by inducing cell cycle arrest at the S or G2/M phase.

ß-Hydroxy-ß-methylbutyrate Suppresses NF-ĸB Activation and IL-6 Production in TE-1 Cancer Cells.

BACKGROUND/AIM: Stress reactions, especially those related to surgery, cause poor convalescence of cancer patients. ß-Hydroxyß-methylbutyrate (HMB) is known to regulate excessive inflammation in the body. The objective of this work was to investigate the capacity of HMB to suppress activation of nuclear factor-kappa B (NF-ĸB) and production of interleukin-6 (IL-6) in a human esophageal squamous cell carcinoma cell line (TE-1). MATERIALS AND METHODS: Cell proliferation was measured using the water-soluble tetrazolium-1 method, while tumor necrosis factor alpha (TNFα)-induced IL-6 production was measured using an enzyme-linked immunosorbent assay (ELISA) assay. Nuclear translocation of NF-ĸB was detected by immunofluorescence staining. RESULTS: HMB did not affect cell proliferation. However, HMB suppressed the TNFα-induced increase in IL-6 production in TE-1 cells by inhibiting NF-ĸB activation. CONCLUSION: HMB did not influence TE-1 cell proliferation, but inhibited activation of NF-ĸB and IL-6 production. This result may be useful for improving excessive stress reactions during and after surgery.

Synergistic Effect of Eicosapentaenoic Acid on Antiproliferative Action of Anticancer Drugs in a Cancer Cell Line Model.

BACKGROUND/AIMS: It has been found experimentally and clinically that eicosapentaenoic acid (EPA) exerts an anticancer effect and that it has a minimal adverse event profile relative to other anticancer drugs. Any synergy between EPA and other anticancer drugs could be of therapeutic relevance, especially in elderly or high-risk patients. Therefore, we investigated the synergism between anticancer drugs and EPA experimentally. METHODS: EPA was coadministered in vitro with various anticancer drugs (paclitaxel, docetaxel, 5-fluorouracil and cis-diamminedichloridoplatinum[II]) to TE-1 cells, which were derived from human esophageal cancer tumors. Cell proliferation was measured by the water soluble tetrazolium-1 method. RESULT: Sub-threshold concentrations of EPA, which alone produced no anticancer effect, caused a synergistic suppressive effect on TE-1 cell proliferation when combined with other anticancer agents. CONCLUSION: Coadministration of EPA with other anticancer drugs may represent a new therapeutic paradigm offering a reduced side effect profile.

Anti-influenza A virus effects of fructan from Welsh onion (Allium fistulosum L.).

A fructan that acts as an anti-influenza A virus substance was isolated from hot water extract of the green leafy part of a Welsh onion (Allium fistulosum L.). The structure of the fructan was characterised and elucidated by chemical and spectroscopic analyses. The fructan was composed of terminal (21.0%) and 2,1-linked ß-D-Fruf residues (65.3%) with 1,6-linked ß-D-Glcp residues (13.7%). The molecular weight of the polysaccharide and polydispersity was estimated to be 1.5×10(3) and 1.18, respectively. Although the fructan did not show anti-influenza A virus activity in vitro, it demonstrated an inhibitory effect on virus replication in vivo when it was orally administered to mice. In addition, the polysaccharide enhanced the production of neutralising antibodies against influenza A virus. Therefore, the antiviral mechanism of the polysaccharide seemed to be dependent on the host immune system, i.e., enhancement of the host immune function was achieved by the administration of the polysaccharide. From our observations, the fructan from Welsh onions is suggested to be one of the active principles which exert an anti-influenza virus effect.