Specific inhibition of PI3K p110δ inhibits CSF-1-induced macrophage spreading and invasive capacity

Kellie Mouchemore, N.G. Sampaio, Michael Murrey, E.R. Stanley, B.J. Lannutti, Fiona Pixley

Research output: Contribution to journalArticlepeer-review

30 Citations (Scopus)


Colony stimulating factor-1 (CSF-1) stimulates mononuclear phagocytic cell survival, growth and differentiation into macrophages through activation and autophosphorylation of the CSF-1 receptor (CSF-1R). We have previously demonstrated that CSF-1-induced phosphorylation of Y721 (pY721) in the receptor kinase insert triggers its association with the p85 regulatory subunit of phosphoinositide 3′-kinase (PI3K). Binding of p85 PI3K to the CSF-1R pY721 motif activates the associated p110 PI3K catalytic subunit and stimulates spreading and motility in macrophages and enhancement of tumor cell invasion. Here we show that pY721-based signaling is necessary for CSF-1-stimulated PtdIns(3,4,5)P production. While primary bone marrow-derived macrophages and the immortalized bone marrow-derived macrophage cell line M−/−.WT express all three class IA PI3K isoforms, p110δ predominates in the cell line. Treatment with p110δ-specific inhibitors demonstrates that the hematopoietically enriched isoform, p110δ, mediates CSF-1-regulated spreading and invasion in macrophages. Thus GS-1101, a potent and selective p110δ inhibitor, may have therapeutic potential by targeting the infiltrative capacity of tumor-associated macrophages that is critical for their enhancement of tumor invasion and metastasis.
Original languageEnglish
Pages (from-to)5228–5236
JournalFEBS Journal
Issue number21
Early online date5 Jun 2013
Publication statusPublished - Nov 2013


Dive into the research topics of 'Specific inhibition of PI3K p110δ inhibits CSF-1-induced macrophage spreading and invasive capacity'. Together they form a unique fingerprint.

Cite this