Anticancer Effects of Astaxanthin and α-tocopherol in Esophageal Cancer Cell Lines

Abstract

Background/Aims: Astaxanthin (AX) has been attributed with potential for protecting the organism against different types of cancer due to its anti-oxidant activity. Also several in vivo and in vitro studies suggest certain naturally occurring vitamin E (i.e. α-tocopherol) as promising anticancer agents. We assessed the effect of AX and α-tocopherol (AT) respectively and their combination on human esophageal cancer cell lines to investigate the mechanism of anticancer effect and their therapeutic potential. Materials and Methods: Two human esophageal cancer cell lines (TE-1, TE-4) were exposed to AX (6 to 10μg/mL) and AT (20 to 100μM) for 24 hours. Quantification of proliferation was performed by MTT assay. Cell cycle machinery proteins such as p-AKT, p-p38, cyclin D1, p27 and caspase-3 were investigated by Western blot. Results: Significant inhibition of cell proliferation of AX and AT was observed in TE-4 cell line by a dose-dependent manner. Furthermore, AX and AT as single agents increased the protein expression of p27 and cleaved caspase-3 in TE-4 cell line. The combination of the two agents decreased the expression of cyclin D1, however they did not demonstrate pro-apoptotic effect. Conclusions: AX and AT as single agents are effective at inhibition of cell proliferation and induce apoptosis by the modulation of cell cycle machinery proteins in esophageal cancer cell lines. However, our data could not suggest that their combination has any cooperative apoptotic effect. (Korean J Helicobacter Up Gastrointest Res 2011;11:170-175)

Xanthorrhizol: a review of its pharmacological activities and anticancer properties

“…They reduced not only the expression of p-Akt and cyclin D1, but also exhibited a higher caspase-3 expression than XNT’s treatment alone in both esophageal cancer cells. On the other hand, previous studies indicated that combined astaxanthine and α-tocopherol did not exhibit any cooperative apoptosis, where they increased the expression of p-Akt and maintained caspase-3 levels compared to control [ 91 ]. In fact, astaxanthine or α-tocopherol treatment alone was effective against TE-1 and TE-4 esophageal cancer cells, but not their combination [ 91 ].…”

“…On the other hand, previous studies indicated that combined astaxanthine and α-tocopherol did not exhibit any cooperative apoptosis, where they increased the expression of p-Akt and maintained caspase-3 levels compared to control [ 91 ]. In fact, astaxanthine or α-tocopherol treatment alone was effective against TE-1 and TE-4 esophageal cancer cells, but not their combination [ 91 ]. Thus, we postulate that the addition of XNT to astaxanthine and α-tocopherol may stimulate their antiproliferative properties giving synergistic effects.…”

Antiproliferatory Effects of Crab Shell Extract on Breast Cancer Cell Line (MCF7)

“…Moreover, an antioxidant and antiproliferative effect on a human bladder cancer cell line (T24) has been reported after 48 hours, depending on chitosan concentration [ 25 ]. The effect of one of the compounds derived from chitin, astaxanthin, on a human esophagus cancer cell line (TE-4) over 24, 48, and 72 hours was investigated, and dose-dependent inhibition was observed [ 26 ]. Furthermore, astaxanthin derived from the green alga Haematococcus pluvialis exerted an inhibitory effect on a large intestine cancer cell line (HCT-116) via apoptosis induction [ 27 ].…”

Biocompatible astaxanthin as a novel marine-oriented agent for dual chemo-photothermal therapy

“…showed that AXT has the potential to act as a therapeutic agent in atherosclerotic cardiovascular disease due to its potent antioxidant and anti-inflammatory properties [28]. Compared with inorganic therapeutic agents, AXT can provide a wide variety of benefits as a natural [32–34], non-toxic [35, 36] material that has a high molar extinction coefficient [37, 38]. Additionally, the United States Food and Drug Administration has approved AXT for use as a dietary supplement [31].…”