When most people think of viruses, they visualize dangerous agents that rapidly cause illnesses such as influenza and polio. Surprisingly, virus infections are also responsible for 15% of human cancer deaths worldwide, and there are likely additional undiscovered viruses that cause various human cancers. Furthermore, because infection with Human Immunodeficiency Virus (HIV) suppresses the immune system, HIV infection and AIDS are indirectly implicated in many cases of cancer.
Teams of researchers within Yale Cancer Center’s Molecular Virology program see the viral causes of cancer as an opportunity to prevent cancer, as well as to improve patient survival and outcomes. Determining that a type of cancer is caused by a virus provides new approaches to prevent or treat the cancer. Virally induced tumors, such as the 19,000 cancer diagnoses caused by Human Papillomaviruses (HPV) in men and women every year in the United States—and the hundreds of thousands of such tumors worldwide—can be prevented with vaccines already in use.
Additionally, these tumors express viral proteins that may serve as targets for new anti-viral chemotherapeutic and immunization therapies with the exciting potential to cure. A major effort in the Molecular Virology Program is to identify novel treatment and prevention approaches based on a basic understanding of these viruses and the patient’s responses to infection.
Researchers at Yale are also challenging the notion that all viruses are necessarily bad for you, by constructing viruses that target skin cancer cells, and they are thrilled by the early results. Anthony N. van den Pol, PhD, Professor of Neurosurgery at Yale School of Medicine, is one such researcher who is conducting studies on mice to research a virus that finds melanoma cells on its own and quickly kills them.
Members of the Molecular Virology program within Yale Cancer Center are studying both sides of the viral story—the mechanism of viral carcinogenesis and the use of this information to develop better prevention and treatment strategies, and the tantalizing potential of using altered viruses to kill tumors. Yale’s researchers and clinicians are proud to be at the forefront of innovation as they create new approaches to prevent and treat tumors.
Victories in this arena are already at hand with approved vaccines against HPV, which have caused a significant reduction in HPV infections. These reductions should lead to fewer diagnoses of cervical cancer in women, oropharyngeal (throat) cancer in all populations, and a decrease of many other cancers.