galangin and Colonic-Neoplasms

Isolated and structurally confirmed, eleven flavonoids from propolis were examined for their cytotoxicity toward human colon cancer and human breast cancer cells. Their effect on induction of apoptosis and their antioxidative activities were also evaluated. Six flavonoids induced cytotoxic effects in both cell lines. Luteolin had a marked effect on both cell lines, especially on HCT-116 cells (IC

Topics: Antineoplastic Agents; Antioxidants; Apitherapy; Apoptosis; Breast; Breast Neoplasms; Cell Line, Tumor; Colon; Colonic Neoplasms; Female; Flavonoids; HCT116 Cells; Humans; Luteolin; Nitrites; Oxidants; Oxidation-Reduction; Plant Extracts; Propolis; Superoxides

Galangin is a member of flavonols and found in Alpinia officinarum, galangal root, and propolis. Previous studies have demonstrated that galangin has anti-cancer effects on several cancers, including melanoma, hepatoma, and leukaemia cells. However, anti-cancer activity of galangin on human colon cancer has not been established yet. In this study, we investigated the anti-cancer effects of galangin on two types of human colon cancer cells (HCT-15 and HT-29). We found that galangin induced apoptosis and DNA condensation of human colon cancer cells in a dose-dependent manner. We also determined that galangin increased the activation of caspase-3 and -9, and release of apoptosis inducing factor from the mitochondria into the cytoplasm by Western blot analysis. In addition, galangin induced human colon cancer cell death through the alteration of mitochondria membrane potential and dysfunction. These results suggest that galangin induces apoptosis of HCT-15 and HT-29 human colon cancer cells and may prove useful in the development of therapeutic agents for human colon cancer.

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; Caspase 3; Caspase 9; Cell Line, Tumor; Colonic Neoplasms; Cytoplasm; Female; Flavonoids; Humans; Male; Membrane Potential, Mitochondrial; Mitochondria; Signal Transduction

Two new flavonoids, 3-O-[(S)-2-methylbutyroyl]pinobanksin (1) and 6-cinnamylchrysin (2), were isolated from the EtOAc-soluble fraction of the MeOH extract of Chinese propolis, along with 12 known compounds (3-14). The structures of the isolated compounds were elucidated on the basis of spectroscopic and chemical analyses. The isolated compounds were tested for their antiproliferative activity toward five different cancer cell lines. Benzyl caffeate (13) and phenethyl caffeate (14) showed potent antiproliferative activity toward tested cell lines with a selective activity toward colon 26-L5 carcinoma cell line (EC(50) values: 13, 1.01; 14, 0.30 microM).

Topics: Animals; Antineoplastic Agents; Biphenyl Compounds; Caffeic Acids; China; Chromatography, Thin Layer; Colonic Neoplasms; Drug Screening Assays, Antitumor; Flavonoids; Free Radical Scavengers; Mice; Molecular Structure; Phenylethyl Alcohol; Picrates; Propolis; Spectrophotometry, Infrared; Tumor Cells, Cultured