Article

CD24 expression causes the acquisition of multiple cellular properties associated with tumor growth and metastasis

Department of Cell Biology, University of Groningen, Groningen, Groningen, Netherlands
Cancer Research (Impact Factor: 9.28). 01/2006; 65(23):10783-93. DOI: 10.1158/0008-5472.CAN-05-0619
Source: PubMed

ABSTRACT The glycosylphosphatidylinositol-anchored membrane protein CD24 functions as an adhesion molecule for P-selectin and L1 and plays a role in B-cell development and neurogenesis. Over the last few years, a large body of literature has also implicated CD24 expression in tumorigenesis and progression. Here, we show that ectopic CD24 expression can be sufficient to promote tumor metastasis in experimental animals. By developing a doxycycline-inducible system for the expression of CD24 in breast cancer cells, we have also analyzed the cellular properties that CD24 expression influences. We found that CD24 expression increased tumor cell proliferation. Furthermore, in addition to promoting binding to P-selectin, CD24 expression also indirectly stimulated cell adhesion to fibronectin, collagens I and IV, and laminin through the activation of alpha3beta1 and alpha4beta1 integrin activity. Moreover, CD24 expression supported rapid cell spreading and strongly induced cell motility and invasion. CD24-induced proliferation and motility were integrin independent. Together, these observations implicate CD24 in the regulation of multiple cell properties of direct relevance to tumor growth and metastasis.

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    Cancer Cell 06/2012; · 23.89 Impact Factor
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    • "In line with our observations, CD24 has been shown to be involved in cancer cell motility, invasion, and metastasis (Baumann et al., 2005; Kristiansen et al., 2003; Runz et al., 2008) and shortened patient survival (Kristiansen et al., 2003; Lee et al., 2009). Also consistent with these reports are the facts that CD24 recruits adhesion molecules to lipid rafts (Runz et al., 2008) and that CD24 indirectly stimulates cell adhesion to fibronectin, collagens I/IV, and laminin through the activation of integrins (Baumann et al., 2005). Interestingly, several studies have shown that some breast cancer-initiating stem cells display the characteristic of being low/negative for CD24 expression but high for CD44 (Al- Hajj et al., 2003; Kim et al., 2007). "
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