More importantly, we showed, for the first time, that circHMCU involved the post-transcriptional regulation of PGK1 via miR-4458.Taken together, circHMCU knockdown inhibited cell proliferation, migration, invasion and glycolysis while induced cell apoptosis in BC cells by miR-4458/PGK1 axis. This evidence concerns the gene PGK1 and breast cancer.