As a systems biologist, I focus my research on gene regulation and cell fate decision by integrating experiments with computer modeling, aiming to dissect complex biological systems to advance our understanding and treatment of human diseases, particularly cancer and aging. To this end, my lab is currently working with modelers, statisticians, computer scientists, optical and mechanical engineers, and clinical physicians to study gene networks that control the life and death decisions of cells, particularly, the Rb-E2F gene network switch that controls the balance between cell proliferation and quiescence.