Fig. 2

Heterogeneous MMR IHC in hypermutated gliomas. In tumor 7, which was a post-TMZ IDH1 mutant GBM in a 43 year-old woman (Table 2), clusters of tumor cells retained Msh2 and Msh6 positivity, but were surrounded by Msh2/6-deficient cells (a, b). Tumor 6 was a post-TMZ IDH1 wild-type GBM in a 65 year-old woman (Table 2). Msh6 was lost in many glioma cells (c), but under high power, it was apparent that a subset of cells with identical tumor nuclear morphology retained Msh6 (d, red asterisk). Also note the smaller rounded nuclei in (d), which are most likely lymphocytes and/or oligodendrocytes. Scale bar = 100 μm in (a, b, e), 50 μm in (c, d) and 25 μm in (f)