Pharmacological levels of Withaferin A (Withania somnifera) trigger clinically relevant anticancer effects specific to triple negative breast cancer cells

ABSTRACT: Withaferin A isolated from Withania somnifera (Ashwagandha) has recently become an attractive phytochemical under investigation in various preclinical studies for treatment of different cancer types. In the present study, a comparative pathway-based transcriptome analysis was applied in epithelial-like MCF-7 and triple negative mesenchymal MDA-MB-231 breast cancer cells exposed to concentrations of Withaferin A (WA) which can be detected systemically in in vivo experiments. Whereas WA revealed attenuation of multiple cancer hallmarks the withanolide analogue Withanone (WN), did not exert any of the described effects in these cells at comparable concentrations. Pathway enrichment analysis identified that WA targeted relevant cancer programs related to cell death, cell cycle and proliferation, which could functionally be validated flow cytometrically and by real-time proliferation xCELLigence assay. With respect to cell motility, invasion and metastasis processes, WA was found to strongly decrease MDA-MB-231 invasion as determined by single-cell collagen invasion assay. This is further supported by gene expression changes which demonstrate increased expression of a validated breast cancer metastasis suppressor gene (BRMS1) and concomitant decreased expression of extracellular matrix-degrading proteases (PLAU, PLAT, ADAM8), cell adhesion molecules (integrins, laminins) as well as pro-inflammatory mediators of the metastasis-promoting tumor microenvironment (TNFSF12, IL6, ANGPTL2, CSF1R). Subsequent in silico network analysis listed key node transcription factors regulating these processes (p53, E2F1, CDKN2A, NRF2) and revealed the role of chromatin modifying enzymes (p300, JARID1B) as central master switches, linking multiple anticancer activities of WA. Furthermore, hierarchical clustering analysis of 84 chromatin writer-reader-eraser enzymes revealed that WA treatment of invasive mesenchymal MDA-MB-231 cells reprogrammed their transcription levels more similarly towards the pattern observed in non-invasive MCF-7 cells. In conclusion, taking in account that sub-cytotoxic concentrations of WA target multiple metastatic effectors in therapy resistant triple negative breast cancer, WA based therapeutic strategies hold promise for further (pre)clinical development to defeat aggressive metastatic breast cancer.

ORGANISM(S): Homo sapiens

PROVIDER: GSE53049 | GEO | 2014/04/01

SECONDARY ACCESSION(S): PRJNA230801

REPOSITORIES: GEO