RESUMO
<p><b>OBJECTIVE</b>To analyze the expression of midkine (MK) gene in acute leukemia patients, and explore the relationship between the gene and leukemia.</p><p><b>METHODS</b>The MK gene expression levels were detected by real-time quantitative RT-PCR (RQ-RT-PCR) in bone marrow (BM) of 181 acute leukemia (AL) patients and 31 normal controls.</p><p><b>RESULTS</b>MK gene was expressed in all AL patients, normal controls and AL patients in complete remission (CR). Compared with that in control group and CR group, MK gene expression was significantly increased in AL patients (P < 0.01 and P < 0.05, respectively). No statistical difference was found between CR group and control group. The expression of MK showed a notable increase in all B-ALL subtypes (including pro-B-ALL, common-B-ALL and pre-B-ALL) as well as in adult and childhood B-ALL patients (P < 0.01). Moreover, the gene expression in B-ALL was also significantly higher than that in TALL, HAL and FAB subtypes of AML (P < 0.01). In addition, M2 patients showed significantly increased in MK expression compared with that in normal controls (P < 0.01) and in other FAB subtypes of AML (P < 0.05). Median MK expression level in M3 patients was also significantly higher than that in normal controls (P < 0.05), but there was no statistical difference between M3 and other AL subtypes excepting for M2 and B-ALL. MK expression in CD34 positive patients was significantly higher than that in CD34 negative ones (P < 0.01) and within M2 patients, MK expression was higher in patients with t (8 ;21) than in those without the translocation (P < 0.05).</p><p><b>CONCLUSION</b>MK gene expression is increased with different levels in B-ALL, M2 and M3 patients, which provides novel insights into the leukemogenesis of acute leukemia.</p>