In human breast cancer, the elevated expression of U34-modifying enzymes Elp3 and Ctu1/2, catalyzing the mcm5s2-U34 tRNA modification, directly promoted the translation of oncoprotein DEK in turn binding to the LEF1-IRES sequence to increase the translation of the oncogenic LEF-1 mRNA and promote the invasion and metastasis of breast cancer cells [72]. This evidence concerns the gene CTU1 and breast cancer.