DAPT suppresses the proliferation of human glioma cell line SHG-44

Objective: To explore the suppressing effect of γ-secretase inhibitor DAPT on proliferation of human glioma cell line SHG-44 in vitro and its mechanism. Methods: The SHG-44 cell was treated by DAPT with different concentration. The proliferation of cells was detected by MTT assay; cell cycle and TSC of CD133⁺ were determined by flow cytometry analysis technique; the key factor in Notch signaling pathway (Notch-1, Delta-1, Hes-1) was measured by reverse transcrip tase-polymerase chain reaction and western blotting. Results: DAPT inhibited the growth and proliferation of SHG-44 cells significantly(P<0.05). And the inhibiting effect on SHG-44 cells produced by DAPT showed a dose-dependent manner. DAPT increased the rate of cells in G₀/G₁ phase of SHG-44 cells, while it decreased the rate of cells in S phase. TSC of CD133⁺ was significantly reduced after DAPT treated SHG-44 cells. The expression of protein and mRNA of Notch-1, Delta-1 and Hes-1 were gradually downregulated with the increase of DAPT doses. Conclusions: DAPT can downregulate these key factor in Notch signaling pathway, reduce the TSC of CD133+ and inhibit the proliferation of SHG-44 cells.