To examine the role of hsa_circ_0023404 and its target miR-217/MARK1 axis in endometrial cancer cell lines, The RT-qPCR was applied to determine the level of hsa_circ_0023404, miR-217 and MARK1 mRNA in human endometrial endothelial cell (HEEC) and three human endometrial cancer cells (RL95-2, KLE and Ishikawa). The gene discussed is MARK1; the disease is endometrial cancer.