Anticancer activity and mediation of apoptosis in human HL-60 leukaemia cells by edible sea cucumber (Holothuria edulis) extract
W.A.J.P. Wijesinghe a, You Jin Jeon a,⇑, Perumal Ramasamy b, Mohd Effendy A. Wahid c,
Charles S. Vairappan b,⇑ a b c School of Marine Biomedical Sciences, Jeju National University, Jeju 690-756, Republic of Korea
Laboratory of Natural Products Chemistry, Institute for Tropical Biology and Conservation, Universiti Malaysia Sabah, Kota Kinabalu 88440, Sabah, Malaysia
Marine Biotechnology Institute, Universiti Malaysia Terengganu, Kuala Terengganu, Terengganu, Malaysia
a r t i c l e
i n f o
Article history:
Received 14 September 2012
Received in revised form 18 January 2013
Accepted 21 January 2013
Available online 4 February 2013
Keywords:
Holothuria edulis
Edible sea cucumber
Anticancer
HL-60 leukaemia cells
Functional food
a b s t r a c t
Sea cucumbers have been a dietary delicacy and important ingredient in Asian traditional medicinal over many centuries. In this study, edible sea cucumber Holothuria edulis was evaluated for its in vitro anticancer potential. An aqueous fraction of the edible sea cucumber (ESC-AQ) has been shown to deliver a strong cytotoxic effect against the human HL-60 leukaemia cell line. An induction effect of apoptotic body formation in response to ESC-AQ treatment was confirmed in HL-60 cells stained with Hoechst 33342 and confirmed via flow cytometry analysis. The up regulation of Bax and caspase-3 protein expression was observed while the expression of Bcl-xL protein was down regulated in ESC-AQ treated HL-60 cells.
Due to the profound anticancer activity, ESC-AQ appears to be an economically important biomass fraction that can be exploited in numerous industrial applications as a source of functional ingredients.
Ó 2013 Elsevier Ltd. All rights reserved.
1. Introduction
Sea cucumbers, also known as Holothuroids (Holothuroidea), are marine invertebrates found in the benthic areas and deep seas.
They are a diverse group of flexible, elongated, worm-like organisms, with a leathery skin and gelatinous body, resembling cucumber (Bordbar, Anwar, & Saari, 2011). Sea cucumbers are one of many marine animals underutilised as food, particularly among the Asian population (Taiyeb-Ali, Zainuddin, Swaminathan, & Yaacob, 2003). They are traditionally consumed raw, dried and boiled in many tropical and subtropical countries (Ozer, Mol, & Varlik,
2004). In addition, sea cucumbers have also been popular as a traditional food tonic in China, Korea and Taiwan for thousands of years (Chen et al., 2011; Wu et al., 2012). These marine invertebrates are usually processed into a dried product which are ranked as high, medium or low in terms of their commercial value based on their species, abundance, appearance, odour, colour, thickness of the body wall and main market demand (Wen, Hu, & Fan,
2010). Sea cucumbers are believed to exert wound healing and reduce arthritis pain in humans, hence are widely used in Asian folk medicine (Aminin, 2001; Mamelona et al., 2007). In addition, re-
⇑ Corresponding authors. Tel.: +82 64 754 3475; fax: +82 64 756 3493 (Y.J. Jeon), tel.: +60 88 320000x2397; fax: +60 88 320291 (C.S. Vairappan).
E-mail addresses: youjinj@jejunu.ac.kr (Y.J. Jeon), csv@ums.edu.my (C.S. Vairappan).
0308-8146/$ - see front matter Ó 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.foodchem.2013.01.058 cent scientific evidence supporting their importance as nutraceuticals and functional foods has attracted interest from nutritionists, pharmacologists and the general public (Zhong, Khan, & Shahidi,
2007). Therapeutic properties and medicinal benefits of sea cucumbers can be linked to the presence of a wide array of bioactives especially triterpene
