Vascular zip codes may lead to targeted
The inner linings of blood vessels, called endothelial cells, are molecularly different in different tissues. When a tissue harbors disease, that disease will put its own signature on its blood vessels. Tumors cause extensive changes in their blood vessels, marking them differently from vessels in normal tissue. Lymphatic vessels in tumors can also carry specific markers. One distinctive feature of tumor blood vessels is that they express RGD-binding integrins, which are not present in normal vessels. This is why RGD peptides show such promise in cancer diagnosis and treatment.
Dr. Ruoslahti devised a novel way to identify peptides that selectively seek out targets in blood vessels anywhere in the body. This method has revealed a wealth of markers—vascular zip codes—in both blood vessels and lymphatics in individual tissues and tumors. Synthetic homing peptides can direct drugs and beneficial proteins into tumors, increasing the efficacy of a drug while reducing its side effects. The first drugs that use homing peptides identified by Dr. Ruoslahti’s laboratory are in clinical trials.