1. Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
2. Department of Biochemistry and Molecular Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
3. Center for Biomolecular Structure and Function, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
4. Department of Veterinary Medicine and Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
5. Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
6. The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, Texas, USA
7. Current address: University of Leeds, Leeds, United Kingdom
8. Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen, Germany