Figure 4.

Inhibitor of DNA binding protein 2 or 4 (Id2 or Id4) overexpression does not significantly affect the cell cycle. (A) Stable glioblastoma multiforme (GBM) neurosphere cells with Id2 and Id4 overexpression were plated in culture medium for 7 days. Cell number was counted at day 3 and 7. There was no significant difference in total cell number between control and Id2 or Id4 transfected cells (n = 6). (B) Cell cycle analysis showed that there was no significant change in cell cycle phase (n = 6). (C) Compared to the control, there was no significant change in the percentage of cells incorporating EdU cells after Id2 or Id4 stable line establishment (n = 4). (D) Expression of cyclin B, D1, E and p21 was detected in control and experimental cells. There was no significant change in the cyclins and p21 levels after Id2 and Id4 overexpression (representative blots of three experiments are shown here).