Pluchea indica tea-leaf extracts exert anti-cancer activity by inducing ROS-mediated cytotoxicity on breast and cervical cancer cells
ISSN: 0007-070X
Article publication date: 28 February 2022
Issue publication date: 3 November 2022
Abstract
Purpose
The study aimed to disclose the anti-cancer activity of Pluchea indica tea leaves by evaluating the cytotoxicity on breast and cervical cancer cells, compared with non-cancer cells.
Design/methodology/approach
Two P. indica extracts were prepared using two solvents, namely hot water (PA) and ethanol (PE). MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) and clonogenic assays were applied to determine cytotoxic effect of both extracts toward cancer cells from human breast (MDA-MB-231 and MCF7) and cervix (SiHa, HeLa and C-33A) and also non-cancer Vero cells. Dichlorofluorescein diacetate (DCFDA)-staining assay was used to quantify the intracellular level of the reactive oxygen species (ROS). Correlation between the quantity of compounds present and the cytotoxicity of the extracts was analyzed by Pearson's method and a possible class of bioactive compounds was proposed based on the highest correlation coefficient (r).
Findings
Significant reduction in cell viability and proliferation capability was observed in all cancer cells after treatment with either PA or PE extract albeit PE was more effective. Lower toxicity was detected in Vero cells, indicating the selectivity and safety of extracts. The intracellular ROS level was augmented in treated cancer cells which were inversely correlated to cell viability, suggesting the cancer toxicity was likely induced by intracellular oxidative stress. As flavonoids were found abundantly in the extracts and flavonoids' content was the most related to the activity (r = 0.815), it was hypothesized that the flavonoids might play crucial roles in cancer cytotoxicity.
Originality/value
P. indica tea-leaf extracts can be a good source of promising anti-cancer agents with reduced side effects for breast and cervical cancer treatment.
Keywords
Acknowledgements
The authors sincerely thank Dr. Ron Beckett (Faculty of Science, Burapha University) for grammatical correction and helpful comments on the manuscript. The Research Unit of Natural Bioactive Compounds for Healthcare Products Development, and the Center of Excellence for Innovation in Chemistry (PERCH-CIC), Ministry of Higher Education, Science, Research and Innovation, Thailand, are gratefully acknowledged for partial support. This work was supported by Science Innovation Facility, Faculty of Science, Burapha University (SIF-IN-55300056).
Funding: This work was financially supported by the Research Grant of Burapha University through National Research Council of Thailand (Grant no. 37.3/2562), Research Grant of Faculty of Science, Burapha University (Grant no. SC05/2563).
Conflict of interest: The authors declare that there is no conflict of interest.
Citation
Iawsipo, P., Poonbud, R., Somtragool, N., Mutapat, P. and Meejom, A. (2022), "
Publisher
:Emerald Publishing Limited
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