Fig. 2

Stem cell markers and cytogenetic characterization of U251MG-Sph. Representative images of adherent U251MG cells and spheres derived from the same cell line (a). Western blot of NESTIN, SOX2, CD44 and GFAP in U251MG-Ahd and -Sph cells (b). Densitometric analysis revealed a significant reduction of GFAP and a significant increase of NESTIN in U251MG-Sph compared to U251MG-Adh (c). Data were also confirmed by qRT-PCR (d). Images of immunofluorescence versus NESTIN and GFAP confirmed western blot data (e). Most common karyogram observed in U251MG-Adh cells as revealed by mFISH (f). Derivative chromosomes are indicated as mar and involved chromosomes 11–10-15, 10–15, 16–4 and 16–3 (g). Ploidy of U251MG-Adh and -Sph was completely superimposable (h), whereas as shown in circos graphs, frequency of chromosomal exchanges is higher in U251MG-Adh (i) than in U251MG-Sph (l). * P < 0.05, ** P < 0.01, *** P < 0.001 (Student’s t-test)