Figure 1.

EZH2 inhibitors delay re-silencing of the FMR1 gene in AZA treated FXS patient cells. GM04025 cells were treated with 10 µM AZA for 3 days. The medium was then replaced with fresh medium containing either 5 µM of GSK126, GSK343 or UNC1999 or an equivalent volume of the vehicle alone (DMSO) (A and B) or 2.5 µM of GSK126 or the equivalent volume of DMSO (C and D). In both sets of experiments medium was replaced with fresh drug containing medium every 3 days. The FMR1 mRNA levels were determined at the indicated time points and were normalized to GUS mRNA levels. The data shown are an average of three independent treatments and error bars represent the standard deviation. The levels of H3K27me3 present on the FMR1 exon 1 in GM04025 cells were analyzed at day 6. The data shown are an average of two independent treatments. The ChIP values were first normalized to the input DNA and are expressed relative to the levels observed in cells treated with AZA alone (B) and relative to GAPDH (D). The error bars represent the standard deviation. E) GM06895 (control) and GM06897 (UFM) cells were treated with either DMSO or 2.5 µM of GSK126 for 3 days. Data shown are an average of 2 independent experiments and error bars represent the standard deviation. * p < 0.05 by unpaired t test.