COPRS and malignant peripheral nerve sheath tumor: Overexpression of COPRS (five to 10-fold) was observed in two MPNSTtissue samples from patients with intragenic NF1 mutations as compared with cutaneous neurofibroma tissue(Bartelt-Kirbach et al. 2009).However, by contrast, these authors detected low expression of COPRS in an MPNST cell line, which was as low as theCOPRS expression level inneurofibroma-derived fibroblast cell cultures.