OBJECTIVETo determine the expression level of silent mating-type information regulation 2 homologue 1 (SIRT1) in bone marrow biopsy tissues among children with acute myeloid leukemia (AML) and analyze its relationship with the prognosis of AML patients.

METHODSA retrospective analysis was performed on the clinical data of 54 children who were diagnosed with AML between July 2009 and April 2012 and who underwent bone marrow biopsy at diagnosis. The expression of SIRT1 in bone marrow was measured by immunohistochemistry. The 54 patients were divided into two groups according to the expression of SIRT1: SIRT1-negative (n=10) and SIRT1-positive (n=44). The SIRT1-positive group was further divided into three subgroups: SIRT1(+) (n=8), SIRT1(++) (n=7) and SIRT1(+++) (n=29) according to the expression levels of SIRT1. Cox multivariate regression analysis was used to determine the unfavorable factors for long survival in children with AML.

RESULTSThe SIRT1(+++) subgroup had a significantly higher mortality than the SIRT1-negative group (P<0.05). Compared with the SIRT1-negative group, the SIRT1-positive group had a significantly lower 2-year overall survival rate (P<0.05) and a significantly lower 2-year event-free survival rate (P<0.05). Cox multivariate regression analysis showed that positive expression of SIRT1 was an unfavorable factor for long-term survival in children with AML, with a risk coefficient of 2.071 (95% CI: 1.017-4.219; P=0.045).

CONCLUSIONSSIRT1 is overexpressed in some of pediatric AML patients, and the overexpression of SIRT1 is associated with poor prognosis.