Development of Phage Assisted Continuous Evolution of the Human Androgen Receptor

Abstract

Prostate cancer (PC) is the second leading cause of male cancer-related deaths in the United States. The central molecule in the development and progression of PC is the androgen receptor (AR), which serves as the most therapeutically relevant target for chemoprevention and drug therapy. First generation AR antagonists, such as bicalutamide and flutamide, exhibit only partial receptor antagonism prompting continued cancer proliferation and metastasis. Thus, the development of more powerful AR antagonists that exhibit pure antagonistic activities would prove to be of great therapeutic value. Unfortunately, despite more than 20 years of crystallization effort focused on the AR, a ligand binding domain (ARlbd) antagonist bound crystal structure remains elusive due to poor expression and and an inherently low protein solubility. In this study we propose a system using phage assisted continuous evolution (PACE; Figure 1.), a novel technique for directed evolution, to overcome the inherently low soubility exhibited by ARlbd to aid in ongoing crystallization efforts.