The present observation that the inhibitor of β-catenin signaling, XAV939, impairs not only the amount of active β-catenin but also the expression of PFKP in a manner similar to that of WNT5A signaling supports the idea that WNT5A impairs aerobic glycolysis in breast cancer cells via reduced β-catenin signaling. This evidence concerns the gene PFKP and breast cancer.