Int J Biol Sci 2018; 14(13):1782-1790. doi:10.7150/ijbs.23586 This issue


Novel CD44-downstream signaling pathways mediating breast tumor invasion

Allal Ouhtit1✉, Balsam Rizeq1,2, Haissam Abou Saleh1, MD Mizanur Rahman1, Hatem Zayed3

1. Department of Biological and Environmental Sciences, College of Arts & Sciences, Qatar University, Doha, Qatar;
2. Biomedical Research Center, Qatar University, Doha, Qatar;
3. Department of Biomedical Sciences, College of Health Sciences, Qatar University, Doha, Qatar.

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Ouhtit A, Rizeq B, Saleh HA, Rahman MDM, Zayed H. Novel CD44-downstream signaling pathways mediating breast tumor invasion. Int J Biol Sci 2018; 14(13):1782-1790. doi:10.7150/ijbs.23586. Available from

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Graphic abstract

CD44, also known as homing cell adhesion molecule is a multi-structural cell molecule involved in cell-cell and cell-extracellular matrix communications. CD44 regulates a number of central signaling pathways, including PI3K/AKT, Rho GTPases and the Ras-MAPK pathways, but also acts as a growth/arrest sensor, and inhibitor of angiogenesis and invasion, in response to signals from the microenvironment. The function of CD44 has been very controversial since it acts as both, a suppressor and a promoter of tumor growth and progression. To address this discrepancy, we have previously established CD44-inducible system both in vitro and in vivo. Next, using microarray analysis, we have identified and validated Survivin, Cortactin and TGF-β2 as novel CD44-downstream target genes, and characterized their signaling pathways underpinning CD44-promoted breast cancer (BC) cell invasion. This report aims to update the literature by adding and discussing the impact of these novel three signaling pathways to better understand the CD44-signaling pathways involved in BC tumor cell invasion.

Keywords: CD44, Breast cancer, Cell-adhesion molecule, Survivin, Cortacti