Christianna Smith Lecture - Brooke M. McCartney '92, Ph.D., Associate Professor of Biological Sciences, Carnegie Mellon University

How will the fruit fly help us to the moon?
The Cancer Moonshot, part of the 21st Century Cures Act passed by Congress in December 2016, aims to increase the availability of new treatments for patients by accelerating the pace of cancer research. How do we reach the moon? Any new clinical innovation is born out of years of basic science research that advances our fundamental knowledge of biology.

 For instance, to understand how mutations in specific genes contribute to complex diseases like cancer, we must first discover how the proteins encoded by these genes contribute to normal cell and tissue biology. This is one of the goals of my lab. Mutation in the human tumor suppressor Adenomatous polyposis coli (APC) is the initiating event in roughly 80% of all colorectal cancers. Why do mutations in APC initiate cancer? This would be an easier question to answer if the historical paradigm of one gene-one protein-one function fully explained the molecular workings of a cell. Instead, APC proteins are the quintessential multi-taskers. My lab explores how APC proteins control cell-cell communication through Wnt signal transduction and how they govern cell shape, tissue architecture, and intracellular networks through the actin assembly activity of Formins. Our research is greatly accelerated by the fruit fly, Drosophila melanogaster, which serves as an experimentally tractable model system to discover the relationships between genes, proteins, and functions. Drosophila genes are easy to manipulate and fruit fly cells utilize a highly conserved toolbox of cellular mechanisms, so what we learn about fly APC proteins can be directly translated to human APC proteins.  In the 20th century fruit flies were the first animals to go into space, and in the 21st century they are going to help us shoot for the moon.