Autophagy Inhibition Enhances the Mitochondrial-Mediated Apoptosis Induced by Mangrove (Avicennia marina) Extract in Human Breast Cancer Cells

Handle URI:
http://hdl.handle.net/10754/550089
Title:
Autophagy Inhibition Enhances the Mitochondrial-Mediated Apoptosis Induced by Mangrove (Avicennia marina) Extract in Human Breast Cancer Cells
Authors:
Esau, Luke; Sagar, Sunil; Bajic, Vladimir B. ( 0000-0001-5435-4750 ) ; Kaur, Mandeep
Abstract:
Aims: Avicennia marina (AM) is a widely distributed mangrove plant that has been used in traditional medicine for centuries for the treatment of a number of diseases. The objective of the present study was to evaluate the leaf ethyl acetate extract of AM for its cytotoxic and apoptotic potential along with in-depth investigations of its mechanism of action in breast cancer MCF-7 cells. Study Design: The ethyl acetate extract of leaves and stems of AM was tested against estrogen positive breast cancer cell line MCF-7 using various assays. Place and Duration of Study: The study was carried out at King Abdullah University of Science and Technology, Thuwal, Saudi Arabia, from July 2013-June 2014. Methodology: Dose- and time-dependent growth inhibition of cancer cells was measured using MTT assay. The mechanisms of apoptosis induction were determined using various assays: phosphatidylserine exposure, caspase-3/7 activation, mitochondrial membrane potential disruption, reactive oxygen species (ROS) production, cell cycle analysis, autophagy, and protein expression using western blotting. The modulation of apoptotic genes (p53, Mdm2, NF-kB, Bad, Bax, Bcl-2 and Casp7) was also determined using real time PCR. Results: The AM extract inhibited breast cancer cell growth and induced apoptosis in a concentration dependent manner. We demonstrated a non-classical mode of apoptosis induction in MCF-7 cells by AM extract, where ROS production altered the mitochondrial membrane potential to induce apoptosis. Breast cancer cells treated with 200 µg/ml concentration of AM extract showed increased ROS production and disrupted MMP but no PARP-1 cleavage and a marked decrease in Caspase-7 protein levels (24 and 48 h) were detected. A significant amount of autophagy was also observed at the same concentration. However, treatment of MCF-7 cells with 200 µg/ml of AM extract along with the inhibition of autophagy by chloroquine, significantly increased the apoptosis from 20% to 45%. Conclusion: Our data provide evidence that AM extract triggers ROS-mediated autophagy as well as caspase-independent apoptosis. The results also strengthen the view that concurrent targeting of apoptotic and autophagic pathways may provide effective therapeutic strategy against cancer.
KAUST Department:
Computational Bioscience Research Center (CBRC)
Citation:
Autophagy Inhibition Enhances the Mitochondrial-Mediated Apoptosis Induced by Mangrove (Avicennia marina) Extract in Human Breast Cancer Cells 2015, 5 (3):304 European Journal of Medicinal Plants
Publisher:
SCIENCEDOMAIN international (SDI)
Journal:
European Journal of Medicinal Plants
Issue Date:
10-Jan-2015
DOI:
10.9734/EJMP/2015/14181
Type:
Article
ISSN:
22310894
Additional Links:
http://www.sciencedomain.org/abstract.php?iid=791&id=13&aid=7245
Appears in Collections:
Articles; Computational Bioscience Research Center (CBRC)

Full metadata record

DC FieldValue Language
dc.contributor.authorEsau, Lukeen
dc.contributor.authorSagar, Sunilen
dc.contributor.authorBajic, Vladimir B.en
dc.contributor.authorKaur, Mandeepen
dc.date.accessioned2015-04-14T13:02:42Zen
dc.date.available2015-04-14T13:02:42Zen
dc.date.issued2015-01-10en
dc.identifier.citationAutophagy Inhibition Enhances the Mitochondrial-Mediated Apoptosis Induced by Mangrove (Avicennia marina) Extract in Human Breast Cancer Cells 2015, 5 (3):304 European Journal of Medicinal Plantsen
dc.identifier.issn22310894en
dc.identifier.doi10.9734/EJMP/2015/14181en
dc.identifier.urihttp://hdl.handle.net/10754/550089en
dc.description.abstractAims: Avicennia marina (AM) is a widely distributed mangrove plant that has been used in traditional medicine for centuries for the treatment of a number of diseases. The objective of the present study was to evaluate the leaf ethyl acetate extract of AM for its cytotoxic and apoptotic potential along with in-depth investigations of its mechanism of action in breast cancer MCF-7 cells. Study Design: The ethyl acetate extract of leaves and stems of AM was tested against estrogen positive breast cancer cell line MCF-7 using various assays. Place and Duration of Study: The study was carried out at King Abdullah University of Science and Technology, Thuwal, Saudi Arabia, from July 2013-June 2014. Methodology: Dose- and time-dependent growth inhibition of cancer cells was measured using MTT assay. The mechanisms of apoptosis induction were determined using various assays: phosphatidylserine exposure, caspase-3/7 activation, mitochondrial membrane potential disruption, reactive oxygen species (ROS) production, cell cycle analysis, autophagy, and protein expression using western blotting. The modulation of apoptotic genes (p53, Mdm2, NF-kB, Bad, Bax, Bcl-2 and Casp7) was also determined using real time PCR. Results: The AM extract inhibited breast cancer cell growth and induced apoptosis in a concentration dependent manner. We demonstrated a non-classical mode of apoptosis induction in MCF-7 cells by AM extract, where ROS production altered the mitochondrial membrane potential to induce apoptosis. Breast cancer cells treated with 200 µg/ml concentration of AM extract showed increased ROS production and disrupted MMP but no PARP-1 cleavage and a marked decrease in Caspase-7 protein levels (24 and 48 h) were detected. A significant amount of autophagy was also observed at the same concentration. However, treatment of MCF-7 cells with 200 µg/ml of AM extract along with the inhibition of autophagy by chloroquine, significantly increased the apoptosis from 20% to 45%. Conclusion: Our data provide evidence that AM extract triggers ROS-mediated autophagy as well as caspase-independent apoptosis. The results also strengthen the view that concurrent targeting of apoptotic and autophagic pathways may provide effective therapeutic strategy against cancer.en
dc.publisherSCIENCEDOMAIN international (SDI)en
dc.relation.urlhttp://www.sciencedomain.org/abstract.php?iid=791&id=13&aid=7245en
dc.rightsThis is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.en
dc.titleAutophagy Inhibition Enhances the Mitochondrial-Mediated Apoptosis Induced by Mangrove (Avicennia marina) Extract in Human Breast Cancer Cellsen
dc.typeArticleen
dc.contributor.departmentComputational Bioscience Research Center (CBRC)en
dc.identifier.journalEuropean Journal of Medicinal Plantsen
dc.eprint.versionPublisher's Version/PDFen
kaust.authorEsau, Lukeen
kaust.authorSagar, Sunilen
kaust.authorBajic, Vladimir B.en
kaust.authorKaur, Mandeepen
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