After that, a more precise algorithm was used to bolt these candidates: Firstly, KM-plot analysis in TCGA was conducted to find candidate genes associated with BC poor prognosis; Secondly, RT-qPCR was performed to define the downregulated genes with miR-217-5p mimics; Thirdly, we searched previous researches to locate KLF5 as our final target of miR-217-5p which was associated with BC poor prognosis and had been reported as important oncogenic transcription in BC [25, 26]. Here, KLF5 is linked to breast cancer.