Scientists have identified a gene responsible for stopping the movement of cancer from the lungs to other parts of the body, indicating a new way to fight one of the world’s deadliest cancers.
By identifying the cause of this metastasis, which often happens quickly in lung cancer and results in a bleak survival rate, scientists are able to explain why some tumors are more prone to spreading than others. The newly discovered pathway, detailed in Molecular Cell (2014; doi:10.1016/j.molcel.2014.06.021), may also help researchers understand and treat the spread of melanoma and cervical cancers. The pathway involves the kinase LKB1 and its control of metastatic behavior.
“Lung cancer, even when it’s discovered early, is often able to metastasize almost immediately and take hold throughout the body,” said Reuben J. Shaw, PhD, professor of molecular and cell biology at the Salk Institute in La Jolla, California, and a Howard Hughes Medical Institute early career scientist. “The reason behind why some tumors do that and others don’t has not been very well understood. Now, through this work, we are beginning to understand why some subsets of lung cancer are so invasive.”
Lung cancer, which also affects nonsmokers, is the leading cause of cancer-related deaths in the country (estimated to be nearly 160,000 this year). The United States spends more than $12 billion on lung cancer treatments, according to the National Cancer Institute. Nevertheless, the survival rate for lung cancer is dismal: 80% of patients die within 5 years of diagnosis largely due to the disease’s aggressive tendency to spread throughout the body.
To become mobile, cancer cells override cellular machinery that typically keeps cells rooted within their respective locations. Deviously, cancer can switch molecular anchors protruding from the cell membrane (called focal adhesion complexes) on and off, preparing the cell for migration. This allows cancer cells to begin the processes to traverse the body through the bloodstream and take up residence in new organs.