Induction of HT-29 Colon Cancer Cells Apoptosis by Pyrogallol with Growth Inhibiting Efficacy Against Drug-Resistant Helicobacter pylori
Authors: Seemaisamy Revathi
Faruck L Hakkim
Neelamegam R Kumar
Muthukalingan Krishnan
Kayalvizhi Nagarajan
Luay Rashan
Sidgi S A A Hasson
Mohammed Al-Buloshi
Farideh Javid
Hamid A Bakshi
Journal: Anti-cancer agents in medicinal chemistry (2019)
Discipline: PHARMACOLOGY & TOXICOLOGY
Keywords: Acacia nilotica; HT-29; Helicobacter pylori; apoptosis; colon cancer
Affiliations: Department of Zoology, Periyar University, Salem, Tamil Nadu, India, Research Center, Dhofar University, Salalah, Oman, Insect Molecular Biology Laboratory, Department of Environmental Biotechnology, Bharathidasan University, Tiruchirappalli, Tamil Nadu, India, Department of Pharmacy, School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield, United Kingdom, Immunology Division, Department of Microbiology & Immunology, College of Medicine and Health Sciences, Sultan Qaboo's University, Muscat, Oman

Abstract:  Background: Colon cancer is the most aggressive form of cancers, that causes 0.5 million deaths per year around the globe. Targeting colon cancer by conventional therapeutic options elicits toxicity. Traditional medicines take a lead to alleviate the existing clinical challenges. Objective: To investigate antibacterial activity against Helicobacter Pylori and in vitro anti-colon cancer activity by Acacia nilotica extract (ACE) and its active constituent pyrogallol. Methods: Pyrogallol isolated from A. nilotica by column chromatography and HPLC and structure was elucidated by spectral analysis. Antibacterial activity was done by flow cytometry. Cytotoxicity was measured by MTT assay. Apoptotic morphology and nuclear fragmentation were assessed with AO/ethidium bromide and DAPI staining. DNA fragmentation was done by electrophoresis. Western blot used to analyze the molecular mechanism of apoptosis. Cell cycle arrest was determined using flow cytometry of propidium iodide stained cells. Cell migration was determined by wound healing assay. Results: ACE (20 µg/ml) and pyrogallol (10 µg/ml) treatment reduced the survival of H.pylori at 61% and 62%, respectively. MTT results show that HT-29 cells are more sensitive to pyrogallol with an IC50 value of 35μg/ml compared to ACE. Pyrogallol treated HT-29 cells reached dead state i.e. late apoptotic state with severe nuclear fragmentation. Pyrogallol elicits dose dependent DNA fragmentation in HT-29 cells. Pyrogallol induced apoptosis by simultaneous down-regulation of Bcl-2 and up-regulation of BAX and cytochrome c. Pyrogallol arrested HT-29 cells in S and G2/M phase of cell cycle. Further pyrogallol exhibited marked antimetastatic potential by inhibiting the migration of HT-29 cells dose dependently. Conclusion: Both ACE and pyrogallol repressed the growth of H.pylori and as significant anti-colon cancer agent. 

Retracted: No

PubPeer comments:
 Figure 2. Panels in A) show H. pylori treated with ACE, while panels in B) show H. pylori treated with pyrogallol. * Panel  3h in Figure 2A appears to share some similarities with panel  2h in Figure 2B, as marked in green and blue boxes. * The blue group of dots appears to be visible twice in panel  3h in Figure 2A. * Some percentages appear to be incorrect, such as  61% in the  3h panel in Figure 2A. Could the authors please check or provide the original figures? ![file] , 
 Figure 5. Several lanes in these two panels appear to look similar. Note the presence of several lighter dots (marked in red and blue), and the similarities between the marker lanes. ![file] ,