500 USING THREE-DIMENSIONAL (3D) CULTURE SYSTEMS TO DELINEATE THE ROLE OF RANKL IN METASTATIC PROSTATE CANCER

Introduction and Objective: While prostate cancer (PCa) is curable at early diagnosis, metastatic PCa is terminal. Recent studies have shown that Receptor Activator of NF kappa-B Ligand, RANKL, markedly enhances bone metastasis (70-100%) by the LNCaP human PCa cell line in mice compared to neo controls (0%). Multivariable tumor and microenvironmental factors in vivo make it difficult to identify the specific cellular response induced by RANKL causing PCa cell homing and growth in bone. Current in vitro 2D cultures lack mechanical and biochemical properties mimicking the bone microenvironment. Our preliminary data showed integrin alpha2 is elevated in RANKL-over-expressing LNCaP cells. PCa interaction with the major bone matrix protein Col1 may contribute to the metastatic potential of LNCAP-RANKL cells. This study used 3D systems to explore the role of RANKL in PCa-bone matrix interactions.