MAST1 and neoplasm: Next, we measured the ability of USP28-depleted cells to impair tumor growth in NSG mice by subcutaneously injecting USP28-KO cells and USP28-depleted cells reconstituted with either USP28 or MAST1 obtained from Fig. 5A. The mice bearing USP28-KO cells treated with cisplatin showed reduced tumor size, volume and weight compared with the mock control group (Fig. 6D, E, Supplementary Table S6).