Fig. 3

Cytosine-Methylated miRNA-181a-5p loses its repressor function. a Correlation study between miRNA-181a-5p and BIM protein expression determined in a cohort of 32 GBM samples. qPCR was used to determine the miRNA-181a-5p expression level. ELISA was performed to estimate BIM Expression. Each open circle represents a GBM sample. Pearson’s correlation test was used to measure the strength of the linear association between the two variables. b Correlation study between miRNA-181a-5p and BIM expression in the GBM samples in which miRNA-181a-5p was unmethylated. qPCR was used to determine the percentage of miRNA-181a-5p expression level. miRNA immunoprecipitation with 5mC antibody was performed to determine the methylation level of miRNA-181a-5p. ELISA was performed to estimate BIM expression. Each open circle represents a GBM sample. Pearson’s correlation test was used to measure the strength of the linear relationship between the two variables. c BIM expression level by ELISA in cells treated with indicated miRNAs. All miRNA (wild-type, mutated or methylated) were obtained from Sigma (France). d Impact of the methylation of miRNA-181a-5p on the BIM expression level via the 3’UTR interaction. Cells were transiently transfected with the indicated miRNA and a BIM 3’UTR-reporter or control reporter. Luciferase activity was determined 48 h after transfection