ERBB2 and breast cancer: Although USP35 is amplified in ~9% of the breast cancer (Fig. 1g), our study revealed that gene amplification is not the major mechanism for higher USP35 expression in breast cancer, since USP35 mRNA levels are significantly higher in luminal (ER+) breast cancer (Fig. 1b), which account for ~70% of the breast cancer, in comparison to TNBC and HER2+ breast cancer.