Figure 3.

Hedgehog signaling affects cell migration and invasion by regulating the expression of MMP-2 and MMP-9 in glioblastoma cells. (A and B) U251 cells were incubated for 24 h with various concentrations of rhSHH or cyclopamine for 24 h. The mRNA levels of MMP-2 and MMP-9 were assayed by reverse transcription quantitative polymerase chain reaction and normalized to GAPDH. (C and D) U251 cells were incubated with various concentrations of rhSHH or cyclopamine for 24 h. The protein levels of MMP-2 and MMP-9 in cell lysates were analyzed by western blot, and band intensity was quantified by densitometry and normalized to β-actin. (E and F) U251 cells were incubated for 24 h with 0.5 µg/ml rhSHH or left untreated (control). U251 cells were either left untreated (control) or pre-treated with GM6001, anti-MMP-2 or MMP-9 anti-MMP-9 neutralizing antibodies for 1 h. Subsequently, Transwell migration and invasion assays were performed. Results are presented as percentages of the control. Values are expressed as the mean ± standard deviation of three independent experiments. ^*P<0.001, compared with controls. MMP, matrix metalloproteinase; rhSSH, recombinant human sonic hedgehog N-terminal peptide.