The cancer stem cell model suggests that a subpopulation of cells within the tumor (the cancer stem cells) is responsible for cancer relapse and metastasis formation. 

Prof. Michal Goldberg and Prof. Eran Meshorer show that spironolactone, apart from inhibiting cancerous cell growth, is also highly toxic to cancer stem cells and can serve as as an anticancer reagent.

Read the paper in Oncogene.