Project description:We carried out a novel clinical biomarker investigation of the blood of systemic mastocytosis patients versus healthy controls; utilizing a new and emerging technology platform Sequential Window Acquisition of all Theoretical fragment-ion spectra mass spectrometry (SWATH-MS). This is the first use of this novel proteomic technique in the study of mastocytosis. A Swath-MS based biomarkers dsicovery study for systemic mastocytosis with orthogonal validation of biomarkers via ELISA.
Project description:Mastocytosis is a myeloproliferative neoplasm characterized by expansion of abnormal mast cells (MCs) in various tissues, including skin, bone marrow, gastrointestinal tract, liver, spleen, or lymph nodes. Subtypes include indolent systemic mastocytosis, smoldering systemic mastocytosis and advanced systemic mastocytosis (AdvSM), a term collectively used for the three most aggressive forms of the disease: aggressive systemic mastocytosis, mast cell leukemia, and systemic mastocytosis with an associated clonal hematological non-mast cell disease (SM-AHNMD). MC activation and proliferation is physiologically controlled in part through stem cell factor (SCF) binding to its cognate receptor, KIT. Gain-of-function KIT mutations that lead to ligand-independent kinase activation are found in most SM subtypes, and the overwhelming majority of AdvSM patients harbor the KITD816V mutation. Several approved tyrosine kinase inhibitors (TKIs), such as imatinib and nilotinib, have activity against wild-type KIT but lack activity against KITD816V. Midostaurin, a broad spectrum TKI with activity against KITD816V, has a 60% clinical response rate, and is currently the only drug specifically approved for AdvSM. While this agent improves the prognosis of AdvSM patients and provides proof of principle for targeting KITD816V as a driver mutation, most responses are partial and/or not sustained, indicating that more potent and/or specific inhibitors are required. Avapritinib, a KIT and PDGFRα inhibitor, was specifically designed to inhibit KITD816V. Early results from a Phase 1 trial suggest that avapritinib has potent antineoplastic activity in AdvSM, extending to patients who failed midostaurin. Patients exhibited a rapid reduction in both symptoms as well as reductions of bone marrow MCs, serum tryptase, and KITD816V mutant allele burden. Adverse effects include expected toxicities such as myelosuppression and periorbital edema, but also cognitive impairment in some patients. Although considerable excitement about avapritinib exists, more data are needed to assess long-term responses and adverse effects of this novel TKI.
Project description:he aim of the project is to characterize qualitatively and quantitatively the interaction of cystatin D in other protein partner and the formation of a complex in whole saliva of patients affected by different forms of systemic mastocytosis (SM), with and without skin involvement. The different composition of the complex could be useful to distinguish patients from healthy subject and the different forms of systemic mastocytosis. Pools of whole saliva from SM (SM-C and SM+C) patients, and from sex/age matched healthy controls were submitted to immunoprecipitation assay using cystatin D antibody followed by SDS-PAGE in reducing conditions, tryptic digestion, and nano-HPLC-high-resolution-MS/MS analysis.
Project description:Mastocytosis is a rare hematological neoplasm characterized by the proliferation of abnormal clonal mast cells (MCs) in different cutaneous and extracutaneous organs. Its diagnosis is based on well-defined major and minor criteria, including the pathognomonic dense infiltrate of MCs detected in bone marrow (BM), elevated serum tryptase level, abnormal MCs CD25 expression, and the identification of KIT D816V mutation. The World Health Organization (WHO) classification subdivides mastocytosis into a cutaneous form (CM) and five systemic variants (SM), namely indolent/smoldering (ISM/SSM) and advanced SM (AdvSM) including aggressive SM (ASM), SM associated to hematological neoplasms (SM-AHN), and mast cell leukemia (MCL). More than 80% of patients with SM carry a somatic point mutation of KIT at codon 816, which may be targeted by kinase inhibitors. The presence of additional somatic mutations detected by next generation sequencing analysis may impact prognosis and drive treatment strategy, which ranges from symptomatic drugs in indolent forms to kinase-inhibitors active on KIT. Allogeneic stem cell transplant (SCT) may be considered in selected SM cases. Here, we review the clinical, diagnostic, and therapeutic issues of SM, with special emphasis on the translational implications of SM genetics for a precision medicine approach in clinical practice.
Project description:A 53 year old woman presented with abnormal liver function tests and subsequently developed intermittent abdominal pain, vomiting and diarrhoea. There were no rash or anaphylactoid reactions. Endoscopic biopsies showed excessive density of eosinophils and immunohistochemical staining for tryptase revealed a florid mast cell infiltrate. A diagnosis of systemic mastocytosis was made by bone marrow biopsy. Systemic mastocytosis is a rare myeloid neoplasm often associated with gastrointestinal symptoms due usually to mediator release but may rarely represent organ infiltration. While endoscopic and routine biopsy appearances are non-specific, suggestive features should lead to staining for mast cell tryptase or CD 117. However, diagnose generally requires bone marrow biopsy. The prognosis in the majority of patients is good and supportive management only is required. For patients with aggressive disease, cytoreductive therapy may be needed.
Project description:To identify SNPs predisposing to systemic mastocytosis (SM) we performed a two stage GWAs consisting of two cohorts from the UK and Germany at stage 1 and three cohorts from Spain, Italy and Denmark at stage 2. At both stages, the SM cases were compared with publicly available controls. The control cohorts used were WTCCC and KORA at stage 1 and the Spanish National DNA bank, InChianti and Inter99 at stage 2. The data available are raw intensity files for 480 SM cases that were genotyped at stage 1. Please see our publication (Galata et al 2020) for details regarding QC of the stage 1 samples.
Project description:Management of Indolent and Smoldering SM is focused on preventing anaphylactic reactions and identifying and avoiding symptom triggers. Skin and gastrointestinal symptoms are managed with H1- and H2-antihistamines. When skin symptoms are not adequately controlled, leukotriene antagonists and oral psoralen combined with ultraviolet therapy may be added. Proton pump inhibitors, sodium cromolyn, and oral corticosteroids may be added for gastrointestinal symptoms. Patients should be prescribed self-injectable epinephrine and trained to treat recurrent cardiovascular symptoms or anaphylaxis. Depression and cognitive impairment require a psychiatric evaluation for tailored treatment. Bone involvement is managed with bisphosphonates and eventually interferon. Omalizumab is effective on all vasomotor symptoms, including anaphylaxis, but not on respiratory, musculoskeletal, and neuropsychiatric symptoms. A cytoreductive treatment is not recommended unless anti-mediator therapy has failed. Venom immunotherapy is mandatory for patients with Hymenoptera venom allergy. There is no curative option for patients with advanced SM. The available therapeutic options include tyrosine-kinase inhibitors and cladribine, with variable duration and extent of response. Imatinib mesylate was the first drug approved for SM lacking the cKIT D816V mutation; dasatinib and nilotinib are ineffective. Midostaurin is active on both wild-type and mutant cKIT D816V, while Avapritinib is a selective cKIT D816V inhibitor: they are approved for the treatment of advanced SM. Cladribine is a purine analog with significant activity against monocytes that were thought to have a common progenitor with mast cells. Allogeneic stem cell transplantation is usually performed in younger selected patients.
Project description:In approximately 20 to 30% of patients with systemic mastocytosis (SM), an associated clonal hematological nonmast cell lineage disorder (AHNMD) is diagnosed. Although SM may be considered to be closely related to the myeloproliferative disorders (MPDs), it is unknown whether JAK2(V617F+) MPD may occur as AHNMD in patients with SM. We here describe five patients with SM and co-existing chronic idiopathic myelofibrosis (SM-CIMF). In five of five patients, we detected the SM-related KIT mutation D816V, and in four of five patients, the MPD-related JAK2 mutation V617F. Surprisingly, JAK2(V617F) was found not only in the AHNMD component of the disease but also in microdissected mast cells in all four JAK2(V617F)-positive cases. Conversely, in two of the five patients, KIT(D816V) was found not only in neoplastic mast cells but also in microdissected CD15(+) neoplastic myeloid cells. Control experiments showed that 10 indolent SM patients without associated MPD did not carry the JAK2 mutation V617F and that 15 CIMF patients without SM did not carry the KIT mutation D816V. Altogether, these data suggest that KIT(D816V+) SM can co-exist with JAK2(V617F+) CIMF and that, in some of these SM-CIMF cases, the two mutations are present in the neoplastic cells of both disease components.
Project description:Fibroblastic/myofibroblastic neoplasms represent a broad, and occasionally diagnostically challenging, category of soft tissue neoplasms. A subset of these tumors defy conventional classification. However, with the advent of next-generation sequencing, the identification of disease-defining molecular alterations is gradually improving their subclassification. Following identification of two index cases of a distinctive fibroblastic neoplasm with a fusion gene involving PRRX1 and NCOA1, we performed a retrospective review to further characterize this entity. We identified two additional cases, including one with a fusion between PRRX1 and NCOA2. The average patient age was 38?years, and three patients were female. Two tumors occurred on the neck, and the others involved the groin and thigh. Tumors were centered in the subcutis and ranged from 2.3 to 14.0 cm (average 5.8 cm). Morphologically, they were predominantly hypocellular, with focal hypercellularity. They were composed of monomorphic spindle-stellate cells with a vague fascicular pattern. The nuclei were bland with only rare mitotic activity, and occasional multinucleation. The intervening stroma was typically abundant and ranged from myxoid to collagenous, with frequent rope-like collagen bundles. Three of the cases had a prominent vasculature ranging from numerous small curvilinear vessels to ectatic and branching staghorn-like vessels. Immunohistochemistry was negative for desmin, smooth muscle actin, S100, CD34, keratin, and epithelial membrane antigen. Each of the patients was treated by simple excision and none of the tumors were associated with local recurrence or metastasis. Based on their unique morphological and molecular attributes, we believe this represents a novel fibroblastic tumor for which we have tentatively proposed the name "PRRX-NCOAx-rearranged fibroblastic tumor."
Project description:Mastocytosis is a rare disease characterized by KIT-driven expansion and accumulation of neoplastic mast cells in various tissues. Although mediator symptoms related to mast cell activation can impose a symptom burden in cutaneous disease and across the spectrum of systemic mastocytosis subtypes, the presence of an associated hematologic neoplasm and/or organ damage denotes advanced disease and the potential for increased morbidity and mortality. In addition to the revised 2016 World Health Organization classification of mastocytosis, a new diagnostic and treatment toolkit, tethered to enhanced molecular characterization and monitoring, is poised to transform the management of patients with advanced systemic mastocytosis (advSM). Although the efficacy of midostaurin and novel selective KIT D816V inhibitors, such as avapritinib (BLU-285), have validated KIT as a therapeutic target, the clinical and biologic heterogeneity of advSM requires that we reimagine the blueprint for tackling these diseases and use tools that move beyond KIT-centric approaches.