MUS81 and gastric cancer: As shown in Fig. 3a and b, MK1775 potently suppressed cell proliferation in a concentration-dependent manner and had a lower IC50 value in MUS81 knockdown gastric cancer cells than in MUS81 wild-type cells, and the 2D colony formation assay also showed less cell colony formation in MUS81 knockdown cells after MK1775 exposure (Fig. 3c and d).