Prevalence and clinical characteristics of N-terminally truncated WT1 expression in acute myeloid leukemia.

Overexpression of the Wilms' tumor gene 1 (WT1) was observed in most leukemia cells. In addition to four major isoforms of WT1, an N-terminally truncated isoforms (sWT1) has been identified. We separately quantified the transcript levels of sWT1 and full-length WT1 (fWT1) in 237 patients with acute myeloid leukemia (AML). sWT1 expression was observed in 45 of 237 (19.0%) AML patients, particularly in acute promyelocytic leukemia (59.3%). Although sWT1 expression was not associated with other genetic mutations and prognosis, fWT1 expression level in sWT1-expressing AML was significantly higher than that in un-expressing AML. These results suggested the possible cooperation of sWT1 and fWT1 in the pathophysiology of AML, while further analysis is required.