WT1(17AA+)剪接变异体在白血病中表达

Objective: To investigate the expression pattern of Wilms' tumor gene WT1 (17AA+) isoform in different leukemia cell lines and primary hone marrow cells from patients with different subtypes of acute leukemia. Methods: The leukemia cell lines included K562, SHI, Jurkat, NB4, NB4/WT1A, and NB4/WT1D cells, etc. The primary hone marrow cells were collected from 79 patients initially diagnosed as acute leukemia. The expression levels of WT1 gene and WT1 (17AA+) isoform were determined by real-time quantitative reverse transcriptase polymerase chain reaction (RQ-RT-PCR). The ratio of WI1 (17AA+)/WT1 was calculated. In the meanwhile, the clinical data from each patient were well documented. Results: The expression levels of WT1 gene (WT1/ABL) in K562, SHI, NB4, BN4/WT1A, and NB4/WT1D cell lines were 2 to 3 magnitudes higher than that in Jurkat and U937 cell lines. The ratios of WT1 (17AA+)/WT1 in K562, SHI, Jurkat, U937, NB4, NB4/WT1A and NB4/WTID were 0.51, 0.41, 0.25, 0.12, 0.53, 0.19 and 0.62, respectively, suggesting a dominant expression of WT1 (17AA+) isoform in K562 and NB4 cells. The median expression level of WT1 gene (WT1/ABL) in 79 newly diagnosed acute leukemia patients was 1.02, ranging from 0.03 to 34.17, which was statistically higher than that in 23 non leukemia controls with median WT1N expression level of 0.0017 (P＜0.001). Furthermore the median ratio of WT1 (17AA+)/WT1 in 79 newly diagnosed acute leukemia patients was 0.64, ranging from 0.30 to 0.93, and there was no statistical difference in the ratios of WT1 (17AA+) /WT1 among different subtypes of acute leukemia (F=0.152, P=0.979). Conclusion: The WT1 gene is expressed in leukemia cell lines and primary leukemia cells with a significantly higher level of the WT1 (17AA+) isoform, and there were no statistical difference in the ratios of WT1 (17AA+)/WT1 among different subtypes of acute leukemia.