In searching for new treatments for castration-resistant prostate cancer, Christopher Evans and team revealed that a promising new drug – referred to as AZD0530 – can help by blocking a signaling protein called Src (pronounced "sarck"). The protein specializes in messages that control the growth and spread of cells. Currently, the effectiveness of prostate cancer medications is determined in part by decreases in prostate-specific antigen (PSA) levels; however, PSA levels were not significantly affected by AZD0530, leading the scientists to recommend broadening the indicators of treatment success.