Treatment options forPCa bone metastases remain inadequate and generally palliative, andthere is an urgent need to identify novel therapeutic targets.41 Osteoblasts secrete growth factors includingIL-6 which can induce AR signaling in PCa cells even in the absenceof androgens, as seen during ADT,42−44 and we hypothesizedthat osteoblasts might therefore also induce PCa cell secretion ofactive KLK molecules into the bone microenvironment under androgen-deprivedconditions. The gene discussed is AR; the disease is posterior cortical atrophy.