Abstract
Using a Burkitt lymphoma-like gene expression signature, we recently defined a high-risk molecular high-grade (MHG)
group mainly within germinal centre B-cell like diffuse large B-cell lymphomas (GCB-DLBCL), which was enriched for
MYC/BCL2 double-hit (MYC/BCL2-DH). The genetic basis underlying MHG-DLBCL and their aggressive clinical
behaviour remain unknown. We investigated 697 cases of DLBCL, particularly those with MYC/BCL2-DH (n = 62) by
targeted sequencing and gene expression profiling. We showed that DLBCL with MYC/BCL2-DH, and those with BCL2
translocation, harbour the characteristic mutation signatures that are associated with follicular lymphoma and its high-grade
transformation. We identified frequent MYC hotspot mutations that affect the phosphorylation site (T58) and its adjacent
amino acids, which are important for MYC protein degradation. These MYC mutations were seen in a subset of cases with
MYC translocation, but predominantly in those of MHG. The mutations were more frequent in double-hit lymphomas with
IG as the MYC translocation partner, and were associated with higher MYC protein expression and poor patient survival.
DLBCL with MYC/BCL2-DH and those with BCL2 translocation alone are most likely derived from follicular lymphoma or
its precursor lesion, and acquisition of MYC pathogenic mutations may augment MYC function, resulting in aggressive
clinical behaviour.
group mainly within germinal centre B-cell like diffuse large B-cell lymphomas (GCB-DLBCL), which was enriched for
MYC/BCL2 double-hit (MYC/BCL2-DH). The genetic basis underlying MHG-DLBCL and their aggressive clinical
behaviour remain unknown. We investigated 697 cases of DLBCL, particularly those with MYC/BCL2-DH (n = 62) by
targeted sequencing and gene expression profiling. We showed that DLBCL with MYC/BCL2-DH, and those with BCL2
translocation, harbour the characteristic mutation signatures that are associated with follicular lymphoma and its high-grade
transformation. We identified frequent MYC hotspot mutations that affect the phosphorylation site (T58) and its adjacent
amino acids, which are important for MYC protein degradation. These MYC mutations were seen in a subset of cases with
MYC translocation, but predominantly in those of MHG. The mutations were more frequent in double-hit lymphomas with
IG as the MYC translocation partner, and were associated with higher MYC protein expression and poor patient survival.
DLBCL with MYC/BCL2-DH and those with BCL2 translocation alone are most likely derived from follicular lymphoma or
its precursor lesion, and acquisition of MYC pathogenic mutations may augment MYC function, resulting in aggressive
clinical behaviour.
Original language | English |
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Pages (from-to) | 1329–1341 |
Number of pages | 13 |
Journal | Leukemia |
Volume | 34 |
Early online date | 16 Dec 2019 |
DOIs | |
Publication status | Published - 1 May 2020 |