HK2 and posterior cortical atrophy: Owing to these potentially advantageous characteristics of hK2 as a PCa biomarker, we investigated the possibility of targeting free hK2 in an androgen-dependent PCa model using 111In-radiolabelled 11B6 - a murine IgG1 hK2-specific monoclonal antibody previously used in immunoassays for free hK2 [24].