1. Department of Stomatology, University of California San Francisco, San Francisco, CA, USA
2. Harvard School of Dental Medicine, Boston, MA, USA
3. Departments of Anatomy and Cellular Biology, Tufts University School of Medicine, Boston, MA, USA
4. Oral Cancer Research Center, University of California San Francisco, San Francisco, CA, USA
5. Laboratory of Cell Biology, Istituto Nazionale per la Ricerca sul Cancro, Genoa, Italy