Induction of apoptosis by pinostrobin in human cervical cancer cells: Possible mechanism of action.

Alka Jaudan,Aparna Dixit,Sapna Sharma,Sri Nurestri Abd Malek,Yi-Hsien Hsieh

doi:10.1371/journal.pone.0191523

Alka Jaudan, Aparna Dixit + Show 3 more

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https://doi.org/10.1371/journal.pone.0191523

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Journal: PloS one	Publication Date: Feb 8, 2018
Citations: 61	License type: CC BY 4.0

Affiliation: Jawaharlal Nehru University, University of Malaya

Abstract

Pinostrobin (PN) is a naturally occurring dietary bioflavonoid, found in various medicinal herbs/plants. Though anti-cancer potential of many such similar constituents has been demonstrated, critical biochemical targets and exact mechanism for their apoptosis-inducing actions have not been fully elucidated. The present study was aimed to investigate if PN induced apoptosis in cervical cancer cells (HeLa) of human origin. It is demonstrated that PN at increasing dose effectivity reduced the cell viability as well as GSH and NO2- levels. Condensed nuclei with fragmented chromatin and changes in mitochondrial matrix morphology clearly indicated the role of mitochondria in PN induced apoptosis. A marked reduction in mitochondrial membrane potential and increased ROS production after PN treatment showed involvement of free radicals, which in turn further augment ROS levels. PN treatment resulted in DNA damage, which could have been triggered by an increase in ROS levels. Decrease in apoptotic cells in the presence of caspase 3 inhibitor in PN-treated cells suggested that PN induced apoptosis via caspase dependent pathways. Additionally, a significant increase in the expression of proteins of extrinsic (TRAIL R1/DR4, TRAIL R2/DR5, TNF RI/TNFRSF1A, FADD, Fas/TNFRSF6) and intrinsic pathway (Bad, Bax, HTRA2/Omi, SMAC/Diablo, cytochrome C, Pro-Caspase-3, Cleaved Caspase-3) was observed in the cells exposed to PN. Taken together, these observations suggest that PN efficiently induces apoptosis through ROS mediated extrinsic and intrinsic dependent signaling pathways, as well as ROS mediated mitochondrial damage in HeLa cells.

Highlights

According to the World Health Organization (WHO), cervical cancer is globally the second most prevalent cancer in women with an estimated 44, 5000 new cases in every year [1]
For confirmation of cytopathic potential of PN against cancer cells, DX a well-known anticancer agent included as a positive control, showed cytotoxicity up to 62.4±4.7% (p 0.001), 33.86±2.0% (p 0.001) and 34.23±7.4% (p 0.05) in HeLa, Ca Ski, SiHa respectively after 48 hours of incubation
It is well known that apoptosis is induced by Reactive Oxygen Species (ROS) generation and depletion of intracellular antioxidant [27], we investigated PN-upregulated ROS production in HeLa cells using

Summary

Introduction

According to the World Health Organization (WHO), cervical cancer is globally the second most prevalent cancer in women with an estimated 44, 5000 new cases in every year [1]. Cervical cancer is a consequence of a long-term infection with human papillomavirus (HPV), and the majority of cases (>84%) occur in low- and middle-income countries. Of 270,000 deaths resulting from cervical cancer worldwide, approximately 85% of these occur in developing countries [1]. HPV infection proceeds by integration of its genome into that of host’s, leading. Instrumentation Research Facility (AIRF), Jawaharlal Nehru University, New Delhi is acknowledged for providing the TEM, FACS, Confocal and Live Cell Imaging Facilities

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