Focus Issue: Refining the War on Cancer

Treating cancer involves not only stemming the growth of the primary tumor but also preventing its progression to metastatic disease. Advances in our understanding of the molecular pathways that transform healthy cells and maintain the proliferative advantage of tumor cells have enabled the development of targeted therapeutics, but preventing drug resistance and the switch to metastatic disease remains challenging. As this week's issue of Science Signaling highlights, dissection of the pathways that regulate inflammation in the tumor microenvironment and insight into the molecular changes that occur in cells in response to therapy may improve clinical strategies, particularly for aggressive breast and skin cancers.