Dr. Runyan's cancer-related research focuses on the cellular process of epithelial-mesenchymal cell transition (EMT). Though it began as a developmental biology investigation in relation to congenital heart disease, Dr. Runyan's lab has continued to look for the links to cancer metastasis.
Dr. Runyan received his post-doctoral training at MD Anderson Cancer Center in a department where the underlying premise was that developmental and carcinogenic mechanisms are highly related. His lab was the first to identify TGFb as a mediator of EMT, Snail2 as a target of TGFb, and the Type III TGFb receptor as a critical part of the process.
TGFb has since become the standard mediator of EMT during experimental metastasis. Dr. Runyan's lab first showed the multi-step nature of EMT with evidence that tumor promoting phorbol esters only initiated a partial EMT and that multiple factors were required to complete cell invasion. This concept has become central to investigations of tumor cell plasticity.
Their recent work has focused on OLFM1 as an invasion-promoting or inhibiting extracellular matrix molecule depending on alternatively spliced isoforms. They found that the invasion promoting isoforms are expressed during normal developmental invasion in the embryonic heart and in aggressive forms of rhabdomyosarcoma and esophageal adenocarcinoma. Ongoing collaborations with AZCC investigators, Ron Heimark and Justina McEvoy, are continuing to compare the developmental and oncogenic aspects of cell invasion.