MiR-675 downregulation correlates with favorable/intermediate karyotypes in de novo acute myeloid leukemia

MicroRNA-675 (miR-675) plays an important role in tumorigenesis and development of various cancers. However, the expression status and the prognostic implication of miR-675 in acute myeloid leukemia (AML) remain largely elusive. In this study, real-time quantitative PCR was carried out to examine miR-675 level in 114 de novo AML patients and 26 controls. The level of miR-675 expression was significantly down-regulated in AML patients (P=0.003). No significant differences were observed between miR-675low and miR-675high cases in clinical parameters including sex, age, white blood cell (WBC) counts, hemoglobin (HB), platelet (PLT) counts, and BM blasts. However, the patients with good/intermediate karyotypes had a higher incidence of miR-675low expression as compared to those with poor karyotype (P=0.033). Moreover, miR-675low group had an obvious tendency towards a lower frequency of complex karyotype than miR-675high group (3% vs 16%, respectively, P=0.057). In regard to the molecular gene mutations, reduced miR-675 expression was closely associated with FLT3-ITD wild type in CNAML patients (P=0.015) and showed a trend in all AML patients (P=0.084). Unfortunately, our data failed to reveal the prognostic value of miR-675 expression among all AML and non-M3 AML as well as CN-AML patients. Taken together, our study suggests that miR-675 down-regulation is a frequent event and is associated with favorable/ intermediate karyotypes in de novo acute myeloid leukemia.