Growth-inhibitory effects of the astaxanthin-rich alga Haematococcus pluvialis in human colon cancer cells

• Published in: Cancer letters 2009-09, Vol.283 (1), p.108-117
• Main Authors: Palozza, Paola, Torelli, Cristiana, Boninsegna, Alma, Simone, Rossella, Catalano, Assunta, Mele, Maria Cristina, Picci, Nevio
• Format: Article
• Language: English
• Subjects: Apoptosis; Apoptosis - drug effects; Astaxanthin; Blotting, Western; Breast cancer; Cell cycle; Cell Cycle - drug effects; Cell Line, Tumor; Cell Proliferation - drug effects; Cell survival; Chromatography, High Pressure Liquid; Colon; Colonic Neoplasms - metabolism; Colorectal cancer; Eukaryota - chemistry; Gene Expression - drug effects; Haematococcus pluvialis; Hematology, Oncology and Palliative Medicine; Human colon cancer cells; Humans; In Situ Nick-End Labeling; Studies; Xanthophylls - isolation & purification; Xanthophylls - pharmacology
• ISSN: 0304-3835; 1872-7980
• DOI: 10.1016/j.canlet.2009.03.031

Abstract The growth-inhibitory effects of the astaxanthin-rich Haematococcus pluvialis were studied in HCT-116 colon cancer cells. H. pluvialis extract (5–25 μg/ml) inhibited cell growth in a dose- and time-dependent manner, by arresting cell cycle progression and by promoting apoptosis. At 25 μg/ml of H. pluvialis extract, an increase of p53, p21WAF-1/CIP-1 and p27 expression (220%, 160%, 250%, respectively) was observed, concomitantly with a decrease of cyclin D1 expression (58%) and AKT phosphorylation (21%). Moreover, the extract, at the same concentration, strongly up-regulated apoptosis by modifying the ratio of Bax/Bcl-2 and Bcl-XL, and increased the phosphorylation of p38, JNK, and ERK1/2 by 160%, 242%, 280%, respectively. Growth-inhibitory effects by H. pluvialis were also observed in HT-29, LS-174, WiDr, SW-480 cells. This study suggests that H. pluvialis may protect from colon cancer.