NEDD4 Family of E3 Ubiquitin Ligases in Breast Cancer: Spotlight on SMURFs, WWPs and NEDD4.

Massively parallel sequencing, genomic and proteomic technologies have provided near complete resolution of signaling landscape of breast cancer (BCa). NEDD4 family of E3-ubiquitin ligases comprises a large family of proteins particularly, SMURFs (SMURF1, SMURF2), WWPs and NEDD4 which are ideal candidates for targeted therapy. However, it is becoming progressively more understandable that SMURFs and NEDD4 have "split-personalities". These molecules behave dualistically in breast cancer and future studies must converge on detailed identification of context specific role of these proteins in BCa. Finally, we provide scattered clues of regulation of SMURF2 by oncogenic miRNAs, specifically considering longstanding questions related to regulation of SMURF1 and WWPs by miRNAs in BCa. SMURFS, WWPs and NEDD4 are versatile regulators and represent a fast-growing field in cancer research and better understanding of the underlying mechanisms will be helpful in transition of our knowledge from a segmented view to a more conceptual continuum.