Researchers at Washington University School of Medicine in St. Louis have developed a nanotherapy that is effective in treating mice with multiple myeloma, a cancer of bone marrow immune cells. From left are first author Deepti Sood Gupta, PhD, and co-senior authors Michael H. Tomasson, MD, and Gregory M. Lanza, MD, PhD. (Image Credit: Robert Boston/Washington University in St. Louis)
Researchers at Washington University School of Medicine in St. Louis have designed a nanoparticle-based therapy that is effective in treating mice with multiple myeloma, a cancer of immune cells in the bone marrow. Targeted specifically to the malignant cells, these nanoparticles protect their therapeutic cargo from degradation in the bloodstream and greatly enhance drug delivery into the cancer cells. These are longtime hurdles in the development of this class of potential cancer drugs.
The nanoparticles carry a drug compound that blocks a protein called Myc that is active in many types of cancer, including multiple myeloma. So-called Myc inhibitors are extremely potent in a petri dish. But when injected into the blood, they degrade immediately. Consequently, the prospect that Myc inhibitors could be a viable treatment in patients has been problematic because past research in animals has shown that the compounds degrade too quickly to have any effect against cancer.
The new study is the first to show that Myc inhibitors can be effective in animals with cancer, as long as the drugs have a vehicle to protect and deliver them into cancer cells. When injected into mice with multiple myeloma, the targeted nanoparticles carrying the Myc inhibitor increased survival to 52 days compared with 29 days for mice receiving nanoparticles not carrying the drug. The researchers also pointed out that the potent Myc inhibitor showed no survival benefit when injected by itself, without the nanoparticle.