Complexity of metastasis-associated SDF-1 ligand signaling in breast cancer stem cells.

Abstract

Tumor metastasis is the main cause of cancer’s lethality. Much research has been dedicated to understand the signaling networks underlying tumor metastasis, with the ultimate goal of identifying signaling nodes or pathways whose inhibition will prevent metastasis. Although previous studies have identified the interaction of the chemokine ligand stromal cell-derived factor-1 (SDF-1) and the G protein-coupled receptor chemokine (C-X-C motif) receptor 4 (CXCR4) as essential for breast cancer metastasis (1), the signaling pathways downstream of SDF-1/CXCR4 have not been well established. In PNAS, Yi et al. use quantitative, liquid chromatography tandem mass spectrometry (LC-MS/MS) to greatly expand our knowledge of the protein phosphorylation networks downstream of SDF-1/CXCR4 in breast cancer stem cells (2).