Dean W. Felsher

My laboratory investigates how oncogenes initiate and sustain tumorigenesis. I have developed model systems whereby I can conditionally activate oncogenes in normal human and mouse cells in tissue culture or in specific tissues of transgenic mice. In particular using the tetracycline regulatory system, I have generated a conditional model system for MYC-induced tumors. I have shown that cancers caused by the conditional over-expression of the MYC proto-oncogene regress with its inactivation. Thus, even though cancer is a multi-step process, the inactivation of one oncogene can be sufficient to induce tumor regression. Now, I am using these model systems to address three questions:

1. How do oncogenes initiate tumorigenesis?
2. How does oncogene inactivation cause tumor regression?
3. How do tumors escape dependence on oncogenes?