The transport efficiency of different ODNs decreased in the following order for AML: T100 > T50 > T10 > C50 > G10 > C10 > A10 > A50; for B-ALL: T100 > T50 > T10 > C50 > G10 > C10 > A50 > A10; B-CLL: T100 > T50 > C50 > G10 > T10 > C10 > A10 > A50; and for T-ALL: T100 > T50 > T10 > C50 > G10 > C10 > A10 > A50. We found that ODNs with different compositions showed the lowest fluorescence in T-ALL among all the tested clinical leukaemia cells, which is not consistent with the high mRNA expression of ENT1/2 in T-ALL41. The gene discussed is SLC29A1; the disease is B-cell chronic lymphocytic leukemia.