MicroRNA study may yield clues to healthy cell self-renewal

Recipient of a 2007 Singer Family Foundation seed grant, Richard Gregory, PhD, is an investigator at Children’s Hospital Boston, an HSCI principal faculty member and an assistant professor at Harvard Medical School. Gregory’s research interests include working to understand the regulation of stem cell self-renewal at the RNA level, in particular the role of microRNAs (miRNAs) in this process. He will use his grant to pursue a screening strategy to look for compounds that prevent production of miRNAs by embryonic stem (ES) cells, keeping these cells in a pluripotent state, i.e., self-renewal state.

The miRNAs are single-stranded RNAs and do not encode proteins but instead target the destruction of other RNAs. Since miRNAs can influence which RNAs are present in a cell, they may play an important role in determining a cell’s fate. Several studies have suggested miRNAs are not necessary for self-renewal in ES cells but do promote differentiation of these cells into mature cells. Gregory will examine which miRNAs drive differentiation to identify targets that, when blocked, could promote the process of self-renewal instead.

Gregory’s current work has implications in cancer and cellular therapeutics. Since data from previous cancer studies show that patients with certain cancers have a deletion or down-regulation of particular miRNAs, this dysfunction may block normal cell development, allowing tumor cells to continue to divide and grow. Gregory’s exploration of a compound to promote self-renewal could lead to a mechanism for generating large quantities of the same-type cell. This would provide an excellent foundation for building cellular therapies.