chlorogenic-acid and Colonic-Neoplasms

Colorectal cancer is a major cause of morbidity and mortality throughout the world. Issues related to the role of diet in cancer prevention and treatment are featured each year, and, in this context, consumption of hydroxycinanmic acids is associated with reduced risk of chronic diseases including cancer. Therefore, the aim of this study was to evaluate the cellular uptake of caffeic and 5-caffeoylquinic acids and their effects on cell viability, cell cycle, and apoptosis in human colon adenocarcinoma cells (HT-29). HT-29 cells were incubated with different concentrations of caffeic and 5-caffeoylquinic acids (1.25 µM to 80.0 µM) from 0.5 to 96 h. Cellular uptake was analyzed by HPLC and LCMS. Cell viability, cell cycle, and apoptosis was measured, respectively, using MTT method and flow cytometry. Caffeic and 5-caffeoylquinic acids are absorbed, isomerized, and metabolized by HT-29 cells. Both compounds were able to reduce HT-29 cell viability, promoting specific changes in the cell cycle and increased the apoptosis rate. Caffeic acid and 5-caffeoylquinic acid showed inhibitory effects on cell growth, suggesting a modulation of the cell cycle with an increase in apoptosis in human colon adenocarcinoma cells.

Topics: Adenocarcinoma; Apoptosis; Caffeic Acids; Cell Cycle; Cell Survival; Colonic Neoplasms; HT29 Cells; Humans; Quinic Acid

Activity-guided fractionation of a methanol extract from the fruit of Manilkara zapota cv. Tikal resulted in the isolation of two new antioxidants, methyl 4-O-galloylchlorogenate (1) and 4-O-galloylchlorogenic acid (2), along with eight known polyphenolic antioxidants, namely, methyl chlorogenate (3), dihydromyricetin (4), quercitrin (5), myricitrin (6), (+)-catechin (7), (-)-epicatechin (8), (+)-gallocatechin (9), and gallic acid (10). Of the 10 polyphenols, 1 showed the highest antioxidant activity (IC(50) = 12.9 microM) in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free-radical assay and displayed cytotoxicity in the HCT-116 and SW-480 human colon cancer cell lines with IC(50) values of 190 and 160 microM, respectively. Compound 2 showed high antioxidant activity (IC(50) = 23.5 microM) in the DPPH free-radical assay and displayed cytotoxicity in the HCT-116 and SW-480 human colon cancer cell lines with IC(50) values of 154 and 134 microM, respectively.

Topics: Antioxidants; Biphenyl Compounds; Colonic Neoplasms; Drug Screening Assays, Antitumor; Flavonoids; Florida; Fruit; Humans; Inhibitory Concentration 50; Manilkara; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Phenols; Picrates; Polyphenols; Stereoisomerism; Structure-Activity Relationship; Tumor Cells, Cultured