A gene that promotes initial development of the most common form of lung cancer and then drives its metastases has been identified by Mayo Clinic researchers in Florida. The study, published in the PLoS ONE yesterday, shows that this gene, matrix metalloproteinase-10 (MMP-10), is a growth factor secreted and then used by cancer stem-like cells to keep themselves vital. These cells then drive lung cancer and its spread, and are notoriously immune to conventional treatment. The findings raise hope for a possible treatment for non-small cell lung cancer, the leading cause of US cancer deaths. When expression of MMP-10 is shut down, lung cancer stem cells lose their ability to develop tumors. When the gene is given back to the cells, they can form tumors again.