An evaluation of relationships between the drug sensitivity of tumor cells from patients with primary ALL and the expression of immunological markers showed moderate correlations between the expression of the myeloid marker, CD33, and resistance to doxorubicin (r = 0.59), vincristine (r = 0.53), and cytarabine (r = 0.62) (Table S7). This evidence concerns the gene CD33 and acute lymphoblastic leukemia.