Skip to main content
. Author manuscript; available in PMC: 2012 Sep 15.
Published in final edited form as: Cancer Res. 2011 Jul 25;71(18):6061–6072. doi: 10.1158/0008-5472.CAN-10-4269

Figure 4. NOTCH ligand JAG1 or DLL1 promotes GBM neurosphere growth in vitro.

Figure 4

(A) Soluble ligand JAG1 peptide treatment for 5 days induced growth of HSR-GBM1 and HSR-GBM2 in a dose-dependent fashion (left and middle panels). JAG1 or DLL1 peptide also induced growth of HSR-GBM3 (right panel). (B) 2 μg/ml JAG1 peptide treatment increased CD133 mRNA expression in HSR-GBM1 (left panel). 2 μg/ml JAG1 peptide treatment also increased the CD15-positive CSLC population in GBM neurospheres detected by immunofluorescence (right panel, n=6 random fields, *: p<0.05, t-test). (C) GBM neurospheres co-cultured with GFP-labeled hBMECs were sorted by flow cytometry and examined clonogenesis by soft agar formation assay. GBM cells formed more colonies when precultured with hBMECs (n=6 wells were counted, *: p<0.01, t-test). In addition, expression of CSLC marker CD133 was also induced at mRNA level in GBM neurospheres pre-cultured with hBMECs compared to those pre-cultured with medium only (right panel, n=6 repeats of this experiment, *: p<0.01, t-test). (D) There was no proliferation change in GBM neurospheres pre-cultured with or without hBMECs, identified by PCNA protein expression using Western blot and percentage of Ki-67 positive population by immunofluorescence. However, CD133 expression was significantly induced in GBM neurospheres pre-cultured with hBMECs (right panel). p-Actin was used as a loading control.