High expression of WT1 gene in acute myeloid leukemias with more predominant WT1+17AA isoforms at relapse

Department of Hematology, The First People's Hospital of Changzhou, Third Affiliated to Suzhou University, Changzhou, China.
Leukemia research (Impact Factor: 2.35). 05/2009; 34(1):46-9. DOI: 10.1016/j.leukres.2009.04.004
Source: PubMed


Real-time quantitative reverse transcriptase polymerase chain reaction method was established for detecting the expression levels of WT1 gene and WT1+17AA isoforms in 226 acute myeloid leukemia (AML) bone marrow (BM) cells. The results showed that WT1 gene was 2-3 logarithms expressed more in AML BM cells at initial diagnosis or relapse than in normal BM cells (p<0.001), with predominant WT1+17AA isoforms expression (the ratio of WT1+17AA/WT1 more than 0.50). Interestingly the ratio of WT1+17AA/WT1 was statistically higher in relapsed AMLs than in initially diagnosed (p=0.01), speculating that WT1+17AA isoforms might participate in AML relapse.

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    • "All of the four isoforms are expressed in primary human solid cancers (Oji et al., 2002) and human primary leukemia (Miwa et al., 1992). Among the four WT1 isoforms, the WT1 17AA(+)KTS(+) isoform is dominantly expressed in all of the above mentioned cancers (Haber et al., 1991; Gu et al., 2010). This suggests that the constitutive expression of the WT1 17AA(+)KTS(+) isoform could rescue the growth inhibitory effect of WT1 antisense oligomers in solid tumors (Oji et al., 1999) indicating the contribution of the WT1 17AA(+)KTS(+) isoform to the growth of cancer cells (Hubinger et al., 2001). "
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