RESUMEN
Objective To observe the differences of biological property of glioma stem cells (GSCs) and glioma non-stem cells (nGSCs), and their related protein expressions. Methods The proliferations of GSCs1, GSCs2 and nGSCs1 and nGSCs2 were detected by CCK8 after two, 4, 6, 8, 10 and 12 d of culture in vitro. The sensitivities of the cells to temozolomide (TMZ) were detected by CCK8 after 2 d of culture. The adhesion abilities of cells were tested by adhesion assay. Transwell assay was used to detect the migration and invasion abilities of cells. The activity of matrix metalloproteinase-2 (MMP-2) was detected by gelatin zymography. Western blotting and immunofluorescence staining were used to detect the protein expressions of Notchl and epidermal growth factor receptor (EGFR). Results The survival rate of nGSCs1 was significantly higher than that of GSCs1 and the survival rate of nGSCs2 was significantly higher than that of GSCs2 after 4, 6, 8, 10 and 12 d of culture (P<0.05). The inhibitory concentration (IC)50 of TMZ for GSCs1, nGSCs1, GSCs2 and nGSCs2 was (1536.0±17.67) μmol/L, (514.5±13.44) μmol/L, (2543.0±39.87) μmol/L, (889.6±17.43) μmol/L, respectively (P<0.05). Number of GSCs1 adhering to extracellular matrix proteins Fibronectin and Collagen I was significantly larger than that of nGSCs1, and that of GSCs2 was significantly larger than that of nGSCs2 (P<0.05). The number of migrated GSCs112 and 24 h of cultivation was statistically larger than that of nGSCs1, and that of GSCs2 was statistically larger than that of nGSCs2 (P<0.05). The number of invaded GSCs124 and 36 h of cultivation was larger than that of nGSCs1, and that of invaded GSCs2 was larger than that of nGSCs2, with statistical differences (P<0.05). The activity of MMP2 secreted by GSCs1 was significantly higher than that by nGSCs1, and that of MMP2 secreted by GSCs2 was significantly higher than that by nGSCs2 (P<0.05). Western blotting showed that the relative protein expression level of EGFR/Notch1 in GSCs1 was significantly lower than that in nGSCs1, and that in GSCs2 was significantly lower than that in nGSCs2 (P<0.05). The results of immunofluorescence staining were consistent with those of Western blotting; EGFR protein strongly expressed in nGSCs and weakly expressed in GSCs; Notch1 protein strongly expressed in GSCs and weakly expressed in nGSCs. Conclusion As compared with the high-EGFR-expressing and proliferative primary glioma cells, the high-Notch1-expressing glioma stem cells have higher activity level of MMP-2,stronger abilities of adhesion, migration and invasion, which may be contributed to glioma treatment resistance and its occurrence.