A new key in breast cancer metastasis

Unlocking the mysteries of cell metastasis, a major cause of cancer mortality, is essential in the development of novel therapies. In this issue of Cancer Cell, Li et al. (2004) identify a link between HER2 and CXCR4, two receptors previously implicated in breast cancer progression and metastasis. HER2 enhances the expression of CXCR4 by stimulating CXCR4 translation and attenuating CXCR4 degradation. Importantly, coexpression of HER2 and CXCR4 occurs in ∼22% of human breast tumors and correlates with poor survival of breast cancer patients.