Upregulated RUNX2 in breast cancer is a target gene of miR-153. (A) Bioinformatics software was used to predict RUNX2 as a putative target gene of miR-153. (B) The mRNA expression level of RUNX2 was detected by reverse transcription-quantitative polymerase chain reaction and found to be upregulated in breast cancer tissue compared with adjacent healthy tissue. **P<0.01 vs. Adjacent. (C) An inverse correlation between miR-153 and RUNX2 mRNA expression in breast cancer tissue samples was identified. (D) WT-RUNX2-3′UTR and MT-RUNX2-3′UTR luciferase reporter plasmids were generated. Following miR-153 overexpression luciferase activity was measured in (E) SK-BR-3 and (F) BT-549 cells. **P<0.01 vs. miR-NC. Adjacent, adjacent healthy tissue; Breast cancer, primary breast cancer tissue; RUNX2, runt-related transcription factor 2; SK-BR-3 and BT-549, human breast cancer cell lines; miR, microRNA; miR-NC, breast cancer cell lines SK-BR-3 and BT-549 transfected with scramble miR; miR-153, breast cancer cell lines SK-BR-3 and BT-549 transfected with miR-153 mimic; WT RUNX2 3′UTR, wild-type 3′UTR of RUNX2 cloned into luciferase reporter plasmid; MT RUNX2 3′UTR, mutant type 3′UTR of RUNX2 cloned into luciferase reporter plasmid.