Loss of 5-hydroxymethylcytosine is a frequent event in peripheral T-cell lymphomas.

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On the Gibbs states of the noncritical Potts model on Z^2

We prove that all Gibbs states of the q-state nearest neighbor Potts model on Z^2 below the critical temperature are convex combinations of the q pure phases; in particular, they are all translation invariant. To achieve this goal, we consider such models in large finite boxes with arbitrary boundary condition, and prove that the center of the box lies deeply inside a pure phase with high probability. Our estimate of the finite-volume error term is of essentially optimal order, which stems from the Brownian scaling of fluctuating interfaces. The results hold at any supercritical value of the inverse temperature.Comment: Minor typos corrected after proofreading. Final version, to appear in Probab. Theory Relat. Field

Combined mutations of ASXL1, CBL, FLT3, IDH1, IDH2, JAK2, KRAS, NPM1, NRAS, RUNX1, TET2 and WT1 genes in myelodysplastic syndromes and acute myeloid leukemias

<p>Abstract</p> <p>Background</p> <p>Gene mutation is an important mechanism of myeloid leukemogenesis. However, the number and combination of gene mutated in myeloid malignancies is still a matter of investigation.</p> <p>Methods</p> <p>We searched for mutations in the <it>ASXL1, CBL, FLT3, IDH1, IDH2, JAK2, KRAS, NPM1, NRAS, RUNX1, TET2 </it>and <it>WT1 </it>genes in 65 myelodysplastic syndromes (MDSs) and 64 acute myeloid leukemias (AMLs) without balanced translocation or complex karyotype.</p> <p>Results</p> <p>Mutations in <it>ASXL1 </it>and <it>CBL </it>were frequent in refractory anemia with excess of blasts. Mutations in <it>TET2 </it>occurred with similar frequency in MDSs and AMLs and associated equally with either <it>ASXL1 </it>or <it>NPM1 </it>mutations. Mutations of <it>RUNX1 </it>were mutually exclusive with <it>TET2 </it>and combined with <it>ASXL1 </it>but not with <it>NPM1</it>. Mutations in <it>FLT3 (</it>mutation and internal tandem duplication), <it>IDH1</it>, <it>IDH2</it>, <it>NPM1 </it>and <it>WT1 </it>occurred primarily in AMLs.</p> <p>Conclusion</p> <p>Only 14% MDSs but half AMLs had at least two mutations in the genes studied. Based on the observed combinations and exclusions we classified the 12 genes into four classes and propose a highly speculative model that at least a mutation in one of each class is necessary for developing AML with simple or normal karyotype.</p

Feline low-grade alimentary lymphoma: an emerging entity and a potential animal model for human disease

Background: Low-grade alimentary lymphoma (LGAL) is characterised by the infiltration of neoplastic T-lymphocytes, typically in the small intestine. The incidence of LGAL has increased over the last ten years and it is now the most frequent digestive neoplasia in cats and comprises 60 to 75% of gastrointestinal lymphoma cases. Given that LGAL shares common clinical, paraclinical and ultrasonographic features with inflammatory bowel diseases, establishing a diagnosis is challenging. A review was designed to summarise current knowledge of the pathogenesis, diagnosis, prognosis and treatment of feline LGAL. Electronic searches of PubMed and Science Direct were carried out without date or language restrictions. Results: A total of 176 peer-reviewed documents were identified and most of which were published in the last twenty years. 130 studies were found from the veterinary literature and 46 from the human medicine literature. Heterogeneity of study designs and outcome measures made meta-analysis inappropriate. The pathophysiology of feline LGAL still needs to be elucidated, not least the putative roles of infectious agents, environmental factors as well as genetic events. The most common therapeutic strategy is combination treatment with prednisolone and chlorambucil, and prolonged remission can often be achieved. Developments in immunohistochemical analysis and clonality testing have improved the confidence of clinicians in obtaining a correct diagnosis between LGAL and IBD. The condition shares similarities with some diseases in humans, especially human indolent T-cell lymphoproliferative disorder of the gastrointestinal tract. Conclusions: The pathophysiology of feline LGAL still needs to be elucidated and prospective studies as well as standardisation of therapeutic strategies are needed. A combination of conventional histopathology and immunohistochemistry remains the current gold-standard test, but clinicians should be cautious about reclassifying cats previously diagnosed with IBD to lymphoma on the basis of clonality testing. Importantly, feline LGAL could be considered to be a potential animal model for indolent digestive T-cell lymphoproliferative disorder, a rare condition in human medicine

Hodgkin lymphoma in a sickle cell anaemia child treated with hydroxyurea

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Recurrent TET2 mutations in peripheral T-cell lymphomas correlate with TFH-like features and adverse clinical parameters.

Inactivating mutations of the Ten-Eleven Translocation 2 (TET2) gene were first identified in myeloid malignancies and more recently in peripheral T-cell lymphomas (PTCLs). In the present study, we investigated the presence of TET2 coding sequence mutations and their clinical relevance in a large cohort of 190 PTCL patients. TET2 mutations were identified in 40 of 86 (47%) cases of angioimmunoblastic T-cell lymphoma (AITL) and in 22 of 58 (38%) cases of peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS), but were absent in all other PTCL entities, with the exception of 2 of 10 cases of enteropathy-associated T-cell lymphoma. Among PTCL-NOS, a heterogeneous group of lymphoma-comprising cases likely to derive from Th follicular (T(FH)) cells similarly to AITL, TET2 mutations were more frequent when PTCL-NOS expressed T(FH) markers and/or had features reminiscent of AITL (58% vs 24%, P = .01). In the AITL and PTCL-NOS subgroups, TET2 mutations were associated with advanced-stage disease, thrombocytopenia, high International Prognostic Index scores, and a shorter progression-free survival

Analyses of TET2 mutations in post-myeloproliferative neoplasm acute myeloid leukemias.

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