title: Withaferin A inhibits experimental epithelial-mesenchymal transition in MCF-10A cells and suppresses vimentin protein level in vivo in breast tumors.
abstract: We have shown previously that withaferin A (WA), a bioactive component of the medicinal plant Withania somnifera, inhibits growth of cultured and xenografted human breast cancer cells and prevents breast cancer development and pulmonary metastasis incidence in a transgenic mouse model. The present study was undertaken to determine if the anticancer effect of WA involved inhibition of epithelial-mesenchymal transition (EMT). Experimental EMT induced by exposure of MCF-10A cells to tumor necrosis factor-α (TNF-α) and transforming growth factor-β1 (TGF-β) was partially reversed by treatment with WA but not by its structural analogs withanone or withanolide A. Combined TNF-α and TGF-β treatments conferred partial protection against MCF-10A cell migration inhibition by WA. Inhibition of TNF-α and TGF-β-induced MCF-10A cell migration by WA exposure was modestly attenuated by knockdown of E-cadherin protein. MCF-7 and MDA-MB-231 cells exposed to WA exhibited sustained (MCF-7) or transient (MDA-MB-231) induction of E-cadherin protein. On the other hand, the level of vimentin protein was increased markedly after 24 h treatment of MDA-MB-231 cells with WA. WA-induced apoptosis was not affected by vimentin protein knockdown in MDA-MB-231 cells. Protein level of vimentin was significantly lower in the MDA-MB-231 xenografts as well as in MMTV-neu tumors from WA-treated mice compared with controls. The major conclusions of the present study are that (a) WA treatment inhibits experimental EMT in MCF-10A cells, and (b) mammary cancer growth inhibition by WA administration is associated with suppression of vimentin protein expression in vivo.
authors.affiliation: Department of Pharmacology & Chemical Biology, and University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
authors.forename: Joomin
authors.initials: J
authors.lastname: Lee
authors.forename: Eun-Ryeong
authors.initials: ER
authors.lastname: Hahm
authors.forename: Adam I
authors.initials: AI
authors.lastname: Marcus
authors.forename: Shivendra V
authors.initials: SV
authors.lastname: Singh
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology / Q000627:therapeutic use*; D017209:Apoptosis / Q000187:drug effects; D001940:Breast / Q000187:drug effects / Q000473:pathology; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects; D058750:Epithelial-Mesenchymal Transition / Q000187:drug effects*; D005260:Female; D006801:Humans; D008819:Mice, Nude; D016212:Transforming Growth Factor beta / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D014746:Vimentin / Q000032:analysis / Q000378:metabolism*; D054358:Withanolides / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D016212:Transforming Growth Factor beta; D014409:Tumor Necrosis Factor-alpha; D014746:Vimentin; D054358:Withanolides; C009684:withaferin A
keywords: EMT; breast cancer; vimentin; withaferin A