Figure 1
mir-27a upregulation is recognized in silico and confirmed in adenoma and CRC tissue analysis. (A) The heatmap shows the differentially expressed microRNA in an adenoma tissue series (n=21) with respect to normal mucosa (E-MTAB-813).14 The red arrow indicates miR-27a high levels in adenoma samples. (B) The differentially expressed miRNAs in 13 epithelial CRC samples and four normal tissues (GSE35602) are visualized in the Volcano plot (red squares; fold change >2, P≤0.05);15 miR-27a (green square) is arrowed. Green lines indicate the fold change and P-value thresholds. (C) The Venn diagram shows the number of differentially expressed miRNAs identified in independent and publicly available CRC data sets analysed by microarray (blue; GSE35602)15 or RNA-seq (yellow; TCGA COAD data set).16 Only the shared miRNAs and their relative expression levels are indicated in the table below the diagram. Fold change >1.5; P<0.01. (D) The box plot depicts miR-27a levels assessed by quantitative reverse transcriptase-PCR in our normal tissues, adenomas (n=32) and CRC samples (n=80) classified according to tumour stages (stages I–II, n=48; stages III–IV, n=32). (E) Representative in situ hybridization (ISH) of miR-27a at different stages of colorectal tumourigenesis (original magnifications × 10 and × 5)
