Expression of embryonic stem cell markers SOX2 and nestin in dermatofibrosarcoma protuberans and dermatofibroma

Methods: With appropriately reacting external and internal controls, we examined 24 examples of DFSP for SOX2 and nestin. For comparison, we included 10 dermatofibromas (DFs). Results: All 24 cases of DFSP were immunoreactive for nestin but negative for SOX2. The DFs were both nestin-negative and SOX2-negative. Conclusions: The observed staining pattern may indicate that DFSP derives from a subtype of nestin-immunoreactive mesenchymal stem cell that is different from the nestin- and SOX2-positive cell population of the perifollicular mesenchyme. Alternatively, nestin expression in DFSP may represent a recapitulation of the staining pattern in early embryogenesis without necessarily indicating that the nestin-positive cells represent stem cells. Also, DFSP may derive from hair follicle-associated mesenchymal stem cells that have lost their SOX2 expression. Sellheyer K, Nelson P, Patel RM. Expression of embryonic stem cell markers SOX2 and nestin in dermatofibrosarcoma protuberans and dermatofibroma.