Expression of BLM mRNA in leukemia and its clinical significance

Abstract

Objective To investigate the correlation between the expression level of BLM and its clinical significance in leukemia. Methods 125 bone marrow specimens of inpatients and outpatients with leukemia were collected in Anhui provincial hospital from January 2011 to December 2011.125 leukemia patients were diagnosed and classified into acute leukemia (AL, n=66) and chronic myelogenous leukemia (CML, n=59) by Morphologic and Immunologic criteria, 5 non-tumor individuals were included as control group.The BLM mRNA expressions were by reverse transcription-polymerase chain reaction(RT-PCR).The specimens were devided into groups according to the age, gender, leukemia type, peripheral blood leukocyte counts, hepatomegalia and(or) splenomegaly, fusion gene, chromosome karyotype, whether first visit and transplantation.The expression of BLM gene in each group and the correlation with above factors were retrospectively analysed.The statistical methods such as chi-square test, single factor variance analysis, t test and Pearson correlation test were mainly used. Results BLM mRNA was detected in leukemia. In bone marrow cells, the BLM gene expression was positive in 71 patients and negative in 54 patients.But none of 5 non-tumor bone marrow cells expressed BLM gene.The difference of BLM expression between patients and controls was statistically significant in two groups, i.e. peripheral blood leukocyte counts and fusion gene (χ2=14.730, 22.399; P<0.05), but there is no statistical significant differences in other groups.The expressions of BLM mRNA in leukemia patients who had been treated with chemotherapy were lower than those newly diagnosed (0.1788±0.1091 vs 0.3276±0.2016; P<0.05).Moreover, BLM mRNA level in post-bone marrow transplant patients was lower than those not treated (0.1271±0.1009 vs 0.2902±0.2034; P<0.05).Pearson correlation analysis showed that higher BLM mRNA expression positively correlated with fusion gene (r=0.357, P<0.01) and chromosome abnormality (r=0.279, P<0.05). Conclusion The BLM mRNA expression level of measurement can be used as judgment for leukemia patients disease severity and the index of prognosis, testing the level may provide a basis for clinical and curative effect judgment.（Chin J Lab Med，2012,35：1130-1134） Key words: Leukemia; RecQ helicases; Bone marrow cells; Reverse transcriptase polymerase chain reaction