SKP1 and breast carcinoma: Yang et al. investigated the radiosensitization effect of MLN4924, an SKP1, Cullins, and F-box protein E3 ubiquitin ligase substrate inhibitor [46], which is known to stimulate growth arrest, apoptosis, and the DNA-damage response; they observed that MLN4924 is a potent radiosensitizing target of breast cancer in the SK-BR-3 breast cancer cell line.