Fig. 3.

mTOR hyperactivation induces aberrant expression of DNMTs. A Protein levels of DNMTs, S6K, P-S6K, and TSC1 determined by Western blot analysis in WT and TSC1^−/− MEFs after treatment with DMSO or rapamycin (500 nM) for 24 h. B Protein levels of DNMTs, S6K and P-S6K determined by Western blot analysis in SNU423 and SNU449 cells subjected to starvation (cultured in complete medium without serum, glucose, and amino acids) for 4 h or 24 h. C Protein levels of DNMTs, S6K and P-S6K determined by Western blot analysis in SNU423 and SNU449 cells starved for 24 h and then recovered by culture in complete medium. D Effect of inhibiting mTOR signalling with rapamycin on DNMT and P-S6K protein expression. Protein levels of DNMTs, S6K and P-S6K determined by Western blot analysis in SNU423 and SNU449 cells treated with rapamycin (500 nM) for the indicated periods. E Protein levels of DNMTs, mTOR, Raptor, and Rictor determined by Western blot analysis in SNU423 and SNU449 cells after siRNA transfection for 48 h. The solid arrows pointed to the correct location of DNMT3B. The values for P-S6K were normalized against the band intensities of S6K. Data were presented as mean ± SD and each assay was performed for three times. Ns, not significant, *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001