부산대학교 도서관

BackgroundIkaros family zinc finger 1 (IKZF1)is a transcription factor with an important role in control-ling hematopoietic proliferation and function, particularly lymphoid cell differentiation. It was previously shown that various mechanisms and expression patterns of Ikaros are linked to a variety of cancers. We hypothesized that aberrant methylation (hypomethylat-ion) of the IKZF1 promoter region might be one of the causes of B-cell acute lymphoblastic leukemia (B-ALL). In B-ALL patients, an increased expression of this gene is a potential cause of B-cell differentiation arrest and proliferation induction. Therefore, as more than 90% of patients with ALL are ＜15 years old, we investigated the methylation pattern of the IKZF1 promoter in childhood B-ALL.MethodsTwenty-five newly diagnosed B-ALL cases were included (all younger than 15 yr). In addi-tion, we selected 25 healthy age- and sex-matched children as the control group. We col-lected the blood samples in EDTA-containing tubes and isolated lymphocytes from whole blood using Ficoll 1.077 Lymphosep. Next, we extracted genomic DNA with the phe-nol/chloroform method. Two microgram of DNA per sample was treated with sodium bisulfite using the EpiTect Bisulfite Kit, followed by an assessment of DNA methylation by polymerase chain reaction (PCR) analysis of the bisulfite-modified genomic DNA.ResultsOur data highlighted a hypomethylated status of the IKZF1 promoter in the ALL cases (96% of the cases were unmethylated). In contrast, the control group samples were parti-ally methylated (68%).ConclusionThis study demonstrated a hypomethylated pattern of the IKZF1 promoter region in child-hood B-ALL, which might underlie the aberrant Ikaros expression patterns that were pre-viously linked to this malignancy.