The Slingerland lab has focused on cell cycle regulation and signal transduction via the TGF-Î² MEK, Src and PI3K pathways. Slingerland discovered the cell cycle inhibitor p27, and has contributed to understanding the G1 to S phase transition. Her group has studied aberrant signal transduction, including Src, PI3K and mTOR pathways, disrupts cell cycle regulators and identified targeted therapies with MEK and Src inhibitors that reverse antiestrogen resistance in breast and ovarian cancer and brought these to clinical trials. Our work on p27 pursues new leads from a longstanding research studying how p27 phsophorylation alters its function. We are investigating how PI3K-mediated C-terminal p27 phosphorylation causes this CDK inhibitor to become an activator of tumor invasion and metastasis by turning on genes that drive EMT and metastasis and upregulates cancer stem cell abundance.