Figure 1

Neurofibromatosis type 1-associated malignant peripheral nerve sheath tumor. (a) Hematoxylin and eosin (H&E × 100). (b) Complete loss of expression of trimethylation at lysine 27 of histone 3 (H3K27me3) on whole-tissue section. (c) Complete loss of expression of H3K27me3 on tissue microarrays. Note the internal positive controls with vessels and inflammatory cells retaining staining. (d) Partial loss of expression of H3K27me3 on whole-tissue section. (e) Partial loss of expression of H3K27me3 on tissue microarrays. (f) Strong and diffuse expression of H3K27me3 on tissue microarrays. (g) Strong and diffuse expression of H3K27me3 on tissue microarrays.