Objective: To explore the effect of LRRC4, a glioma suppressive gene, on blocking U251 cells in G0/G1 by MAPK signaling pathway.
Methods: LRRC4 was transfected into U251 cells, and at 24 hour of post-transfection, cells were split at a 1:3 dilution, challenged with 500 microg /mL G418 and formed a stable transfected clone pool. RT-PCR, Northern blot and Western blot were used to identify the stable transfectants. ERK, JNK and P38 expression changes were analyzed by Western blot. FACS analysis, Luciferase reporter gene assay and Western blot were used to detect the cell cycle and cyclin D1.
Results: LRRC4 down-regulated the expression of phosphorylated ERK2 and up-regulated the expression of total protein JNK2 (a key molecule of MAPK signaling pathway) and phosphorylated c-Jun. LRRC4 decreased the expression of mutation P53, cyclin D1 activation and its expression. U251 cells were blocked in G0/G1 by LRRC4.
Conclusion: LRRC4 can decrease JNK2, up-regulate the phosphoralated c-Jun, down-regulate mutant P53 and cyclin D1, and therefore block U251 cells in G0/G1.