SMURF2 and breast cancer: Two other genes involved in PCP, ligand WNT11 and ubiquitin ligase SMURF2, are amplified in smaller percentages of breast cancer cases (WNT11: in 5.2% of cases in TCGA and 6.7% of cases in METABRIC; SMURF2: in 6.2% of cases in TCGA and 8.1% of cases in METABRIC; Figure 1).