Fascin Is Critical for the Maintenance of Breast Cancer Stem Cell Pool Predominantly via the Activation of the Notch Self‐Renewal Pathway. (21st August 2016)

• Record Type: Journal Article
• Authors: Barnawi, Rayanah; Al‐Khaldi, Samiyah; Majed Sleiman, Ghida; Sarkar, Abdullah; Al‐Dhfyan, Abdullah; Al‐Mohanna, Falah; Ghebeh, Hazem; Al‐Alwan, Monther
• Is Part Of: Stem cells. Volume 34:Number 12(2016:Dec.)
• Page Start: 2799
• Page End: 2813
• Publication Date: 2016-08-21
• Subjects: Breast cancer -- Fascin -- Cancer stem cell -- Metastasis -- Chemoresistance; Cloning -- Periodicals; Clone cells -- Periodicals; Stem cells -- Periodicals; Cell Differentiation -- Periodicals; Cell Division -- Periodicals; Clone Cells -- Periodicals; Hematopoietic Stem Cells -- Periodicals; Stem Cells -- Periodicals; 571.84
• DOI: 10.1002/stem.2473
• Languages: English
• ISSNs: 1066-5099

Abstract

Abstract: An emerging dogma shows that tumors are initiated and maintained by a subpopulation of cancer cells that hijack some stem cell features and thus referred to as "cancer stem cells" (CSCs). The exact mechanism that regulates the maintenance of CSC pool remains largely unknown. Fascin is an actin‐bundling protein that we have previously demonstrated to be a major regulator of breast cancer chemoresistance and metastasis, two cardinal features of CSCs. Here, we manipulated fascin expression in breast cancer cell lines and used several in vitro and in vivo approaches to examine the relationship between fascin expression and breast CSCs. Fascin knockdown significantly reduced stem cell‐like phenotype (CD44 hi /CD24 lo and ALDH + ) and reversal of epithelial to mesenchymal transition. Interestingly, expression of the embryonic stem cell transcriptional factors (Oct4, Nanog, Sox2, and Klf 4) was significantly reduced when fascin expression was down‐regulated. Functionally, fascin‐knockdown cells were less competent in forming colonies and tumorspheres, consistent with lower basal self‐renewal activity and higher susceptibility to chemotherapy. Fascin effect on CSC chemoresistance and self‐renewability was associated with Notch signaling. Activation of Notch induced the relevant downstream targets predominantly in the fascin‐positive cells. Limiting‐dilution xenotransplantation assay showed higher frequency of tumor‐initiating cells in the fascin‐positive group. Collectively, our data demonstrated fascin as a critical regulator of breast CSC pool at least partially via activation of the Notch self‐renewal signaling pathway and modification of the expression embryonic transcriptional factors. Targeting fascin may halt CSCs and thus presents a novel therapeutic approach for effective treatment of breast cancer. Stem Cells 2016;34:2799–2813 Video Highlight:https://youtu.be/GxS4fJ_Ow-o Abstract : Fascin expression in breast cancer cell is critical for the maintenance of cancer stem cells (CSCs) via the up‐regulation of the notch self‐renewal pathway.