Fig. 1

miR-133a-3p is down-regulated in breast cancer cells mediated by DNA methylation. a Foldchange of miR-133a-3p in 17 types of cancer tissues compared to their adjacent normal tissues (left) and expression levels of miR-133a-3p in 1085 breast cancer tissues and 104 normal breast tissues (right) in starBase public database from the TCGA project. b miR-133a-3p levels were detected in 66 pairs of human breast cancer tissues and corresponding adjacent normal tissues by qRT-PCR. c miR-133a-3p levels in breast cancer patients with different tumor grades, sizes and histological, and in patients with different tumor size, with (indicated with ‘yes’) or without (indicated with ‘no’) lymph node metastasis. d Overall survival analysis of breast cancer patients with lymph node metastasis based on miR-133a-3p expression (n = 585, log-rank test). Data was analyzed using Kaplan Meier Plotter (www.kmplot.com). e miR-133a-3p levels in different breast cancer cells and normal breast cells. f miR-133a-3p levels in the parental (Normal) or spheroid (Sphere) MCF-7, MDA-MB-468 and MDA-MB-231 cells. g miR-133a-3p levels in MCF-7, MDA-MB-468, and MDA-MB-231 cells treated with different concentrations of 5-Aza-CdR for 72 h. h A schematic diagram of the CpG island and bisulfite sequencing PCR primers positions in the promoter region of miR-133a-3p (upper) and the methylation levels of miR-133a-3p in MCF-7, MDA-MB-468, and MDA-MB-231 cells treated with 20 μM 5-Aza-CdR for 72 h (lower). Black and white circles represent methylated and unmethylated CpG, respectively. Each row represents an individual sequenced DNA strand. The percentage of methylation in each sequenced region is indicated. i The methylation levels of miR-133a-3p in 3 pairs of human breast cancer tissues (indicated by ‘number # BRCA of the patient’) and the corresponding adjacent normal tissues (indicated by ‘number # NAT of the patient’). *P < 0.05; **P < 0.01; ***P < 0.001