RRC ID 57656
Author Osumi T, Tsujimoto SI, Tamura M, Uchiyama M, Nakabayashi K, Okamura K, Yoshida M, Tomizawa D, Watanabe A, Takahashi H, Hori T, Yamamoto S, Hamamoto K, Migita M, Ogata-Kawata H, Uchiyama T, Kizawa H, Ueno-Yokohata H, Shirai R, Seki M, Ohki K, Takita J, Inukai T, Ogawa S, Kitamura T, Matsumoto K, Hata K, Kiyokawa N, Goyama S, Kato M.
Title Recurrent RARB Translocations in Acute Promyelocytic Leukemia Lacking RARA Translocation.
Journal Cancer Res
Abstract Translocations of retinoic acid receptor-α (RARA), typically PML-RARA, are a genetic hallmark of acute promyelocytic leukemia (APL). However, because a small fraction of APL lack translocations of RARA, we focused here on APL cases without RARA translocation to elucidate the molecular etiology of RARA-negative APL. We performed whole-genome sequencing, PCR, and FISH for five APL cases without RARA translocations. Four of five RARA-negative APL cases had translocations involving retinoic acid receptor-β (RARB) translocations, and TBL1XR1-RARB was identified as an in-frame fusion in three cases; one case had an RARB rearrangement detected by FISH, although the partner gene could not be identified. When transduced in cell lines, TBL1XR1-RARB homodimerized and diminished transcriptional activity for the retinoic acid receptor pathway in a dominant-negative manner. TBL1XR1-RARB enhanced the replating capacity of mouse bone marrow cells and inhibited myeloid maturation of human cord blood cells as PML-RARA did. However, the response of APL with RARB translocation to retinoids was attenuated compared with that of PML-RARA, an observation in line with the clinical resistance of RARB-positive APL to ATRA. Our results demonstrate that the majority of RARA-negative APL have RARB translocations, thereby forming a novel, distinct subgroup of APL. TBL1XR1-RARB as an oncogenic protein exerts effects similar to those of PML-RARA, underpinning the importance of retinoic acid pathway alterations in the pathogenesis of APL.Significance: These findings report a novel and distinct genetic subtype of acute promyelocytic leukemia (APL) by illustrating that the majority of APL without RARA translocations harbor RARB translocations. Cancer Res; 78(16); 4452-8. ©2018 AACR.
Volume 78(16)
Pages 4452-4458
Published 2018-8-15
DOI 10.1158/0008-5472.CAN-18-0840
PII 0008-5472.CAN-18-0840
PMID 29921692
MeSH Animals Bone Marrow Cells / metabolism Bone Marrow Cells / pathology Humans Leukemia, Promyelocytic, Acute / genetics* Leukemia, Promyelocytic, Acute / pathology Mice Nuclear Proteins / genetics Oncogene Proteins, Fusion / genetics Receptors, Cytoplasmic and Nuclear / genetics Receptors, Retinoic Acid / genetics* Repressor Proteins / genetics Retinoic Acid Receptor alpha / genetics* Signal Transduction / genetics Translocation, Genetic* Tretinoin / metabolism Whole Genome Sequencing
IF 9.727
Times Cited 12
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