Quercus acutissima Carruth. root extract triggers apoptosis, autophagy and inhibits cell viability in breast cancer cells

Ethnopharmacological relevance: The bark of Quercus acutissima Carruth. (QA) has long been used by Chinese people to treat noncancerous growths and cancerous ailments. It was traditionally used by Chinese folk to inhibit tumor proliferation in cancerous treatment, but the specific mechanism remain to be elucidated.

Aim of the study: This study investigated the Anticancer activities of QA root extract and its regulatory pathways in two human breast Cancer cell lines (MCF-7 and SUM159).

Materials and methods: Dried QA root barks were extracted by ethanol and used to treat human breast Cancer MCF-7 and SUM159 cells with varying concentrations. The CCK-8 assay, Hoechst 33342 staining assay and wound healing assay were used to detect the cell proliferation, apoptotic cell morphology, and cell migration in each group, respectively. Caspase 3 activity assay kit was used to determine Caspase 3 activity. Western blot was used to measure proteins expression level in Apoptosis and Autophagy pathways (Bcl-W, Caspase 3, Beclin1, LC3 and Atg5). LC-MS was performed to determine the chemical components in QA root extract.

Results: CCK-8 assay showed that QA root extract significantly inhibited cell viability and proliferation in breast Cancer cells by a concentration-dependent manner. Cell wound healing assay indicated that it had high suppression ability on cell migration both in MCF-7 and SUM159 cells. QA root extract treatment induced the morphological and nuclear structural changes in breast Cancer cells including rounded appearance and shrunken nucleus with several nuclear body fragments. Western blot indicated that QA root extract induced mitochondria-mediated Apoptosis by up-regulating Caspase 3 and down-regulating Bcl-W. Moreover, QA root extract up-regulated Beclin1 and Atg5, and activated LC3 in two human breast Cancer cell lines. LC-MS results showed that QA root extract contains high content of bioactive compounds like Coumarins and derivatives, prenol lipids, Flavonoids and tannins.

Conclusions: QA root extract inhibited cell proliferation and migration in MCF-7 and SUM159 cells, and it also induced cell morphology changes and regulated mitochondria-mediated apoptotic cell death and autophagic cell death.