In many MM cases, there is increased activity of fibroblast growth factor receptor 3 (FGFR3), which is associated with a poor prognosis. Increased FGFR3 activity promotes cancer growth and resistance to chemotherapy. We will determine if FGFR3 also alters the proteins outside of the MM cells contributing to its spread. We will test a new therapeutic approach that may interrupt many of the effects of FGFR3. In addition, using a novel yeast system, we will screen drugs and identify other components of the FGFR3 system that would be targets for future therapies.