Pharmacognosy Magazine

ORIGINAL ARTICLE
Year
: 2017  |  Volume : 13  |  Issue : 50  |  Page : 321--328

Induction of apoptosis and cell cycle arrest by flavokawain C on HT-29 human colon adenocarcinoma via enhancement of reactive oxygen species generation, upregulation of p21, p27, and Gadd153, and inactivation of inhibitor of apoptosis proteins


Chung-Weng Phang, Saiful Anuar Karsani, Sri Nurestri Abd Malek 
 Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia

Correspondence Address:
Sri Nurestri Abd Malek
Institute of Biological Sciences University of Malaya Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur
Malaysia

Chalcones have been shown to exhibit anti-cancer properties by targeting multiple molecular pathways. It was, therefore, of interest to investigate flavokawain C (FKC), a naturally occurring chalcone, which can be isolated from Kava (Piper methysticum Forst) root extract. The aim of this study was to investigate the inhibitory effect of FKC on the growth of HT-29 cells and its underlying mechanism of action. Cell viability of HT-29 cells was assessed by Sulforhodamine B assay after FKC treatment. Induction of apoptosis was examined by established morphological and biochemical assays. ROS generation was determined by dichlorofluorescein fluorescence staining, and superoxide dismutase activity was measured using the spectrophotometric method. Western blotting was used to examine the changes in the protein levels. FKC markedly decreased the cell viability of HT-29 cells and the cells showed dramatic changes in cellular and nuclear morphologies with typical apoptotic features. The induction of apoptosis correlated well with the externalization of phosphatidylserine, DNA fragmentation, decreased mitochondrial membrane potential, activation of caspases, and PARP cleavage. This was associated with an increase in reactive oxygen species and a decrease in SOD activity. The protein levels of XIAP, c-IAP1, and c-IAP2 were downregulated, whereas the GADD153 was upregulated after FKC treatment. FKC induced cell cycle arrest at the G1 and G2/M phases via upregulation of p21 and p27 in a p53-independent manner. Our results provide evidence that FKC has the potential to be developed into chemotherapeutic drug for the treatment of colon adenocarcinoma. Abbreviations used: FKC: Flavokawain C; SRB: Sulforhodamine B; ROS: Reactive oxygen species; SOD: Superoxide dismutase; PARP: Poly(ADP-ribose) polymerase ; ER: Endoplasmic reticulum; IAPs: Inhibitor of apoptosis proteins; TUNEL: Transferase dUTP nick end labeling; Annexin V-FITC: Annexin V conjugated with fluorescein isothicyanate


How to cite this article:
Phang CW, Karsani SA, Abd Malek SN. Induction of apoptosis and cell cycle arrest by flavokawain C on HT-29 human colon adenocarcinoma via enhancement of reactive oxygen species generation, upregulation of p21, p27, and Gadd153, and inactivation of inhibitor of apoptosis proteins.Phcog Mag 2017;13:321-328


How to cite this URL:
Phang CW, Karsani SA, Abd Malek SN. Induction of apoptosis and cell cycle arrest by flavokawain C on HT-29 human colon adenocarcinoma via enhancement of reactive oxygen species generation, upregulation of p21, p27, and Gadd153, and inactivation of inhibitor of apoptosis proteins. Phcog Mag [serial online] 2017 [cited 2019 Oct 22 ];13:321-328
Available from: http://www.phcog.com/article.asp?issn=0973-1296;year=2017;volume=13;issue=50;spage=321;epage=328;aulast=Phang;type=0