Targeted cancer drugs are widely used because of their ability to inhibit specific proteins involved in cancer development with fewer side effects compared to chemotherapy drugs. But targeted therapies can often inhibit other unknown proteins. These hidden targets may also contribute to the drug’s anticancer effects and potentially offer a path for the drug to be repurposed for other cancers controlled by the hidden target. In a new study published in Cell Chemical Biology, Moffitt Cancer Center researchers and a collaborator demonstrate this, showing that the ROS1 inhibitor lorlatinib has activity against an additional protein called PYK2. The team also reveals the mechanisms of this inhibition. The article is titled “Differential Network Analysis of ROS1 Inhibitors Reveals Lorlatinib Polypharmacology Through Co-Targeting PYK2.”