Blood: Atypical 3q26/MECOM rearrangement of acute myeloid leukemia is comparable to inv (3)/t (3; 3)

Acute myeloid leukemia (AML), which carries inv (3)/t (q21q26), is recognized by WHO as a unique subtype characterized by invasive sexually transmitted diseases and poor prognosisIn this AML subtype, the enhancer of GATA2 (3q21) translocations to MECOM (3q26), resulting in the meCOM subtype EVI1 overexpression, and GATA2 another unaffected allele gene is single allele gene expressionMDS1-EVI1 expression is blocked due to the 3q26 rearrangement, meCOM full-length transcriptionIn addition to the classic inv (3)/t (3;3), many other 3q26/ MECOM rearrangements associated with poor treatment response were reported in Patients with AMLIn this study, the researchers found that in 33 AML cases with atypical 3q26 rearrangements, MECOM participated in EVI1 overexpression, but no MDS1-EVI1 expression was detectedin addition, these AML patients' 3q26 translocations usually involve super-enhancers of genes active in myelin development (e.gCD164, PROM1, CDK6, or MYC)In more than 50% of cases, alleles specific GATA2 expression was observed, due to an imbalance in alleles lost or unexplained copiesin general, atypical 3q26 rearrangement reproduces the main leukemia mechanisms of inv(3)/t(3;3) AML, i.eEVI1 overexpression driven by enhanced sub-hijacking, MDS1-EVI1 expression deficiency, and potential GATA2 participationtherefore, the researchers believe that atypical 3q26/MECOM and inv (3)/t (3; 3) can be classified as 3q26 rearrangement AML subtypesIn clinical practice, MECOM rearrangement, EVI1 and MDS1-EVI1 expressions can be analyzed to identify 3q re-arrangement AML cases