Acute myeloid leukemia with inv(16)(p13.1q22) and deletion of the 5’MYH11/3’CBFB gene fusion: a report of two cases and literature review.

Abstract

Background Abnormalities of chromosome 16 are found in about 5-8% of acute myeloid leukemia (AML). The AML with inv(16)(p13.1q22) or t(16;16)(p13.1;q22) is associated with a high rate of complete remission (CR) and favorable overall survival (OS) when treated with high-dose Cytarabine. At the inversion breakpoints, deletion of 3’ CBFB has been reported, but most of them were studied by chromosome and fluorescence in situ hybridization (FISH) analyses. The genomic characteristics of such deletions remain largely undefined, hindering further understanding of the clinical significance of the deletions. Case presentation We report here two AML cases with inv(16) and deletion of the 5’ MYH11 /3’ CBFB gene fusion, which were characterized by chromosome, FISH, and single nucleotide polymorphism (SNP) microarray analyses. Both cases have achieved CR for more than three years. Conclusions Deletion of 3’ CBFB in AML with inv(16) is also accompanied with deletion of 5’ MYH11 in all the cases studied by SNP microarray, suggesting that 3’ CBFB and 5’ MYH11 were most likely deleted together as a fusion product of inv(16) instead of occurring separately. In concert with the findings of other published studies of similar patients, our study suggests that deletion of 5’ MYH11 /3’ CBFB in AML with inv(16) may not have negative impact on the prognosis of the disease.

Identification of prognostic signature based on the copy number variation (CNV) and expression in acute myeloid leukemia

“…Previous studies have shown that some of them were associated with AML. CBFB forms fusion genes CBFB/MYH11, which block differentiation in AML [24], but the deletion of CBFB usually was accompanied with the deletion of MYH11, and the deletion of MYH11/CBFB had no negative effect on the prognosis [25]. Our ndings suggested deletion-induced downregulating CBFB expression has positive effects on the prognosis.…”

Natural HDAC‐1/8 inhibitor baicalein exerts therapeutic effect in CBF‐AML

“…The t(8; 21)q(22;22) is a common translocation identified in 40‐50% of FAB‐M2b subtype, and rare cases of M0, M1, and M4 subtypes 6 . Meanwhile, the inv(16) occurs in 5% of AML cases 7 . The abnormality of inv(16) is highly correlated with the AML subtype FAB‐M4 with dysplastic eosinophils in bone marrow (M4E 0 ) 8,9 .…”