This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous QBank, Subject name: Medicine
[{'content': 'Sclerostin is produced by? \nSelect and explain. \nA. Osteocytes, B. Osteoblasts, C. Osteoclasts, D. Chondrocytes', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Sclerostin (SOST) is a glycoprotein produced by osteocytes. They also synthesize receptor activator of nuclear factor kappa B ligand (RANKL). Both of these are involved in regulating bone formation and resorption. EXTRA EDGE: Romosozumab, a humanized monoclonal antibody that binds to sclerostin, prevents sclerostin from exeing this inhibitory effect. Therefore, in the presence of romosozumab, the Wnt signaling pathway is activated leading to bone formation and bone mineral density gain.', 'role': 'assistant'}]