The 8p11 myeloproliferative syndrome (EMS) is an aggressive chronic myeloproliferative disorder (MPD) that is caused by constitutive activation of fibroblast growth factor receptor 1.
Here we describe another case of myeloproliferative neoplasm with chromosome translocation t(8;19) involving FGFR1 gene associated with systemic mastocytosis.
To test the relative contributions of localization and dimerization on kinase signaling, we targeted inducibly dimerizable FGFR1 to the centrosome and other subcellular locations and generated a mutant of the FOP-FGFR1MPN fusion defective in centrosome localization.
We report herein a rare case of a t(1;8)(q25;p11.2) with a TPR-FGFR1 rearrangement, in which the patient presented with myeloproliferative neoplasm-like symptoms and T-lymphoblastic lymphoma.
Hematologic malignancies associated with FGFR1 abnormalities present in heterogeneous forms, including myeloproliferative neoplasm, acute myeloid leukemia (AML), T- or B-lineage lymphoblastic leukemia/lymphoma, and even mixed phenotype acute leukemia.
Here, we report a new translocation at the FGFR1 locus in a patient who carried t(1;8)(q25;p11.2) and presented with myeloproliferative neoplasm-like symptoms.
The KG-1a cell line is developed from a human stem cell myeloproliferative neoplasm as the result of intragenic disruption and a chromosomal translocation of the FGFR1 gene and the FGFR1OP2 gene encoding a protein of unknown function called FOP2 (FGFR1 Oncogene Partner 2).
The introduction of JAK2 mutation testing has changed dramatically the diagnostic algorithms for myeloproliferative neoplasms (MPNs) but there is still a place for conventional cytogenetic analysis in the initial work-up of MPN cases, particularly as this group of myeloid disorders has been expanded to include chronic eosinophilic leukaemia and myeloid neoplasms with abnormalities of the PDGFRA, PDGFRB, and FGFR1 genes.
Important changes include (1) the change of nomenclature of myeloproliferative disorder to myeloproliferative neoplasm emphasizing the clonal nature of these disorders; (2) the classification of mast cell disease as an MPN; (3) the reorganization of the eosinophilic disorders into a molecularly defined category of PDGFRA, PDGFRB and FGFR1-associated myeloid and lymphoid neoplasms with eosinophilia and chronic eosinophilic leukemia, not otherwise specified; and (4) refinement of the diagnostic criteria for PV, ET and PMF incorporating recently described molecular markers, JAK2V617F, JAK2 exon 12 mutations and MPL mutations.
Protein tyrosine kinase abnormalities, including translocations or mutations involving ABL1, JAK2, MPL, KIT, PDGFRA, PDGFRB, and FGFR1, have been used as the basis for classifying myeloproliferative neoplasms (MPN).
The revised 2008 WHO classification system featured the following changes: 1) the term "CMPD" was replaced by "myeloproliferative neoplasm (MPN)," 2) mast cell disease was formally included under the category of MPN, and 3) the subcategory of CEL/HES was reorganized into "CEL not otherwise specified (CEL-NOS)" and "myeloid and lymphoid neoplasms with eosinophilia and abnormalities of PDGFRA, PDGFRB, and FGFR1"; CEL-NOS remained a subcategory of "MPN," whereas the latter neoplasms were now assigned a new category of their own.
The 8p11 myeloproliferative syndrome (EMS) is an aggressive, atypical stem cell myeloproliferative disorder associated with chromosome translocations that disrupt and constitutively activate FGFR1 by fusion to diverse partner genes.
We describe a case of coexisting BCR-ABL negative myeloproliferative disorder and precursor T-cell lymphoblastic lymphoma associated with t(8;13) involving FGFR1 at 8p11 in a 14-year-old boy who presented with generalized lymphadenopathy and an abdominal mass.
The t(8;13) translocation, found in a rare and aggressive type of stem cell myeloproliferative disorder, leads to the generation of a fusion protein between the N-terminal gene product of fused in myeloproliferative disorders (FIM)/ZNF198 and the fibroblast growth factor receptor 1 (FGFR1) kinase domain.