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What is S100 is a marker used in the diagnosis of and explain in detail?
S100 proteins are normally present in cells derived from the neural crest (Schwann cells, and melanocytes), chondrocytes, adipocytes, myoepithelial cells, macrophages, Langerhans cells, dendritic cells, and keratinocytes.S100 protein family are useful as markers for ceain tumors and epidermal differentiation. It can be found in melanomas, schwannomas, neurofibromas, 50% of malignant peripheral nerve sheath tumors, paraganglioma stromal cells, histiocytoma and clear cell sarcomas.