The accumulation of p21/p27/WEE1 as three substrates of CRL induces the G2 cell cycle arrest against cancer cells with the treatment of MLN4924, and the co-treatment of MLN4924 with radiation enhances the induction of G2 cell cycle by the increased accumulation of p21/p27/WEE1 [152–156]. Here, WEE1 is linked to cancer.