It is well known that the aberrant activation of PI3K/Akt pathway is one of the primary causes of diverse cancers.5 The activation of PI3K/Akt signalling through PIP5Kα has been identified in breast cancer and prostate cancer models.10, 11 Therefore, a significant implication of this study is that the regulation of PIP5Kα by NEDD4 can play a role in limiting activation of the PI3K/Akt pathway linked to breast cancer progression (Figure 7). This evidence concerns the gene NEDD4 and breast cancer.