The central role of osteoblasts in the metastasis of prostate cancer

Prostate cancer (PCa) is the most common malignancy in men. Although mortality from PCa has been declining over the past decade, metastasis can substantially shorten survival time and remains a major challenge in maintaining quality of life for survivors. PCa cells preferentially metastasize to bone and typically result in osteoblastic lesions. In the late stages of disease, however, osteolytic lesions are observed. The mechanisms of PCa bone metastasis are still unclear, but relationships between the PCa cells and the bone tissue elements are suspected of being more complex than initially thought. Far from being an innocent bystander, the bone participates actively in the metastatic process and provides the cancer cells with growth factors and a fertile environment. Among the various cells in the bone environment, osteoblasts have a central role through their bidirectional interactions with the PCa cells. This review discusses the possible mechanisms of PCa bone metastasis and highlights the essential role of osteoblasts in the metastasis of PCa to bone.