Ammonia, a waste product of cellular activity, is cleared from the body by the liver and kidneys through a process known as the urea cycle. During the urea cycle, ammonia is converted to urea, and arginine (an amino acid) is generated. When liver cells become cancerous, the urea cycle pathway stops functioning and cancer cells must import arginine from outside the cell. When cancer cells are prevented from importing arginine (via removal of arginine from the diet or genetic removal of the transporter), tumors do not grow, suggesting that arginine is critical for cells. However, the function of arginine in the cell is unclear. Using mass spectrometry and mathematical modeling, Dr. Lesner will identify the fate of arginine as it is metabolized by liver cancer cells in mouse models, and investigate how this is altered by various genetic mutations. Additionally, he will examine how restricting arginine from the diet genetically alters the liver and tumor cells. By understanding how disruption of this metabolic pathway influences liver cancer growth in the context of specific cancer drivers, Dr. Lesner aims to inform new therapeutic strategies. Dr. Lesner received his PhD from The University of Texas Southwestern Medical Center, Dallas and his BA from the University of Wooster, Wooster, Ohio.
