Lynne Bemis, PhD

The complex role of extracellular RNA (exRNA) in health and disease is just beginning to be elucidated. Previously it was thought that RNA molecules could not survive in the circulation or in extracellular locations. However, with improved methods for detecting small RNAs, it has become clear that microRNAs and other small RNA molecules exist in all biological fluids and are expected to play a role very much like cytokines thereby regulating many events in both health and disease. My research focus includes projects on identifying novel RNA molecules as biomarkers for earlier cancer detection, specifically in ovarian cancer. We have identified tRNA fragments in the urine of ovarian cancer patients and are currently exploring the role of these molecules in ovarian cancer cells and determining their ability to distinguish advanced stage ovarian cancer patients from less aggressive disease. In addition, we are developing novel molecular methods to study tRNA fragments (tRFs). These are "fragments that function" and are difficult to study with current methodology because they are a part of a mature tRNA. They are actively processed from mature tRNAs and may have many functions, although the function that we have confirmed, is much like a microRNA. We have shown that a specific tRF, tRF5-Glu is capable of binding to the BCAR3 (breast cancer anti-estrogen) mRNA and blocking expression. Another aspect of extracellular RNA that we study is the mode of their extracellular transport. We have developed a novel method to pull various small noncoding RNAs out from the media, once the media is depleted of a specific noncoding RNA it is possible to study the loss of that RNA molecule on cells grown in hanging drop cultures. In addition, to our work in cancer biology, we are also interested in the role of small RNAs in infectious disease. We are currently studying small RNAs expressed in patients with Lyme disease and in animal models. The field of small RNAs is rapidly expanding and we expect to continue these studies in additional disease sites and processes.