NES and glioma: Endothelial cells that are entering into a proliferative state express nestin.20 However, application of the shape (circulatory) filter did not uncover a relationship between elongated nestin+ cells and PpIX+ cells in lower-grade gliomas (Figure 4D; slope = 0.02 ± 0.02, R2 = 0.07, P = .48, n = 9 IDH1mut gliomas).