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Cells Apr 2024The unfolded protein response is an intricate system of sensor proteins in the endoplasmic reticulum (ER) that recognizes misfolded proteins and transmits information...
TurboID-Based IRE1 Interactome Reveals Participants of the Endoplasmic Reticulum-Associated Protein Degradation Machinery in the Human Mast Cell Leukemia Cell Line HMC-1.2.
The unfolded protein response is an intricate system of sensor proteins in the endoplasmic reticulum (ER) that recognizes misfolded proteins and transmits information via transcription factors to either regain proteostasis or, depending on the severity, to induce apoptosis. The main transmembrane sensor is IRE1α, which contains cytoplasmic kinase and RNase domains relevant for its activation and the mRNA splicing of the transcription factor XBP1. Mast cell leukemia (MCL) is a severe form of systemic mastocytosis. The inhibition of IRE1α in the MCL cell line HMC-1.2 has anti-proliferative and pro-apoptotic effects, motivating us to elucidate the IRE1α interactors/regulators in HMC-1.2 cells. Therefore, the TurboID proximity labeling technique combined with MS analysis was applied. Gene Ontology and pathway enrichment analyses revealed that the majority of the enriched proteins are involved in vesicle-mediated transport, protein stabilization, and ubiquitin-dependent ER-associated protein degradation pathways. In particular, the AAA ATPase VCP and the oncoprotein MTDH as IRE1α-interacting proteins caught our interest for further analyses. The pharmacological inhibition of VCP activity resulted in the increased stability of IRE1α and MTDH as well as the activation of IRE1α. The interaction of VCP with both IRE1α and MTDH was dependent on ubiquitination. Moreover, MTDH stability was reduced in IRE1α-knockout cells. Hence, pharmacological manipulation of IRE1α-MTDH-VCP complex(es) might enable the treatment of MCL.
Topics: Humans; Cell Line, Tumor; Endoplasmic Reticulum-Associated Degradation; Endoribonucleases; Leukemia, Mast-Cell; Membrane Proteins; Protein Serine-Threonine Kinases; Valosin Containing Protein
PubMed: 38727283
DOI: 10.3390/cells13090747 -
International Journal of Molecular... Nov 2023venom-triggered anaphylaxis (HVA) affects up to 8.9% of the general population and is the most frequent cause of anaphylaxis in adults, accounting for approximately 20%...
venom-triggered anaphylaxis (HVA) affects up to 8.9% of the general population and is the most frequent cause of anaphylaxis in adults, accounting for approximately 20% of all fatal anaphylaxis cases. Quite often, a fatal reaction is a victim's first manifestation of HVA. Mastocytosis represents one of the most important risk factors for severe HVA. We analyzed patients with documented fatal HVA for the presence of underlying clonal mast cell disorder (cMCD). Here, we report three cases of fatal HVA, with undiagnosed underlying cMCD identified by the presence of the peripheral blood and/or bone marrow p.D816V missense variant postmortem. In the first case, anaphylaxis was the initial episode and was fatal. In the other two cases, both patients were treated with specific venom immunotherapy (VIT), nevertheless, one died of HVA after VIT discontinuation, and the other during VIT; both patients had cardiovascular comorbidities and were taking beta-blockers and/or ACE inhibitors. Our results point to the importance of screening all high-risk individuals for underlying cMCD using highly sensitive molecular methods for peripheral blood p.D816V variant detection, including severe HVA and possibly beekeepers, for proper management and the need for lifelong VIT to prevent unnecessary deaths. Patients at the highest risk of fatal HVA, with concomitant cardiovascular and cMCD comorbidities, might not be protected from field stings even during regular VIT. Therefore, two adrenaline autoinjectors and lifelong VIT, and possibly cotreatment with omalizumab, should be considered for high-risk patients to prevent fatal HVA episodes.
Topics: Adult; Animals; Humans; Anaphylaxis; Arthropod Venoms; Mast Cells; Hymenoptera; Mastocytosis
PubMed: 38003556
DOI: 10.3390/ijms242216368 -
Polish Archives of Internal Medicine Jun 2024
Topics: Humans; Imatinib Mesylate; Mastocytosis, Systemic; Pyrimidines; Female; Piperazines; Antineoplastic Agents; Benzamides; Male; Middle Aged; Syndrome
PubMed: 38640058
DOI: 10.20452/pamw.16730 -
Diagnosis (Berlin, Germany) Nov 2023To describe patterns observed in antibody titer trendlines in patients with mast cell activation syndrome (MCAS, a prevalent but underrecognized chronic multisystem...
OBJECTIVES
To describe patterns observed in antibody titer trendlines in patients with mast cell activation syndrome (MCAS, a prevalent but underrecognized chronic multisystem inflammatory disorder of great clinical heterogeneity) and offer clinical lessons learned from such pattern recognition.
METHODS
The available records of 104 MCAS patients drawn from the authors' practices were reviewed, including all antibody tests therein.
RESULTS
All patients had positive/elevated antibodies of various sorts at various points, but for most of the antibodies which were found to be positive at least some points, the diseases classically associated with those antibodies were not present, marking such antibodies as clinically insignificant mimickers (likely consequent to inflammatory effects of MCAS on the immune system itself driving spurious/random antibody production) rather than "on-target" and pathogenic antibodies reflecting true disease warranting treatment. We also observed two distinct patterns in trendlines of the titers of the mimickers vs. the trendline pattern expected in a true case of an antibody-associated disease (AAD).
CONCLUSIONS
Our observations suggest most positive antibody tests in MCAS patients represent detection of clinically insignificant mimicking antibodies. As such, to reduce incorrect diagnoses of AADs and inappropriate treatment in MCAS patients, caution is warranted in interpreting positive antibody tests in these patients. Except in clinically urgent/emergent situations, patience in determining the trendline of a positive antibody in an MCAS patient, and more carefully assessing whether the AAD is truly present, is to be preferred.
Topics: Humans; Mastocytosis; Mast Cell Activation Syndrome
PubMed: 37566881
DOI: 10.1515/dx-2023-0032 -
Cureus Dec 2023KIT gene mutations in Ewing sarcomas are rare; however, they are much more frequent in other neoplasms, namely mastocytosis. We describe a case of an adult male with a...
KIT gene mutations in Ewing sarcomas are rare; however, they are much more frequent in other neoplasms, namely mastocytosis. We describe a case of an adult male with a one-year duration of recurrent episodes of pain, swelling, and redness on the proximal phalanx of the third finger of his right hand. A core biopsy suggested a possible mastocytosis. After four years of recurrent episodes and worsening symptoms, an incisional biopsy revealed an Ewing sarcoma with a KIT gene mutation (M541L, on exon 10). KIT gene mutations with gain-of-function were identified in 2.6% of Ewing sarcomas. In this case, the detection of a KIT mutation in an Ewing sarcoma developed at the site of previous mast cell proliferation raises the hypothesis of a possible sarcomatous evolution of the original lesion. To the best of our knowledge, similar cases are not described in the current literature. This is also the first report describing the KIT M541L mutation (exon 10) in Ewing sarcoma.
PubMed: 38222235
DOI: 10.7759/cureus.50537 -
Hematology Reports Mar 2024Factor VII (FVII) deficiency is a rare bleeding disorder that can be classified as congenital or acquired, and the majority of acquired cases are due to vitamin K...
Factor VII (FVII) deficiency is a rare bleeding disorder that can be classified as congenital or acquired, and the majority of acquired cases are due to vitamin K deficiency or liver disease. Isolated acquired FVII deficiency is a rare occurrence and has been associated with inhibitors or auto-antibodies. Here, we describe a patient with polycythemia vera who developed systemic mastocytosis and FVII deficiency simultaneously. FVII deficiency was not caused by inhibitors and improved with antineoplastic treatment. Acquired FVII deficiency has been reported in cases of sepsis, possibly due to proteolytic degradation induced by the activation of monocytes or endothelial cells. Malignancies have been shown to cause a depletion in circulating FVII through the direct binding of cancer cells. This case report suggests a potential association between SM associated with a hematological neoplasm (SM-AHN) and acquired FVII deficiency. Further evaluations are recommended in patients with systemic mastocytosis to gain a better understanding of the relationship between pathological mast cells and clotting factor concentrations.
PubMed: 38534884
DOI: 10.3390/hematolrep16010014 -
Scientific Reports Jan 2024In 70 patients with KIT D816V positive systemic mastocytosis (SM) including 36 patients with advanced SM (AdvSM), we correlated the extent of reported mucosal mast cell...
In 70 patients with KIT D816V positive systemic mastocytosis (SM) including 36 patients with advanced SM (AdvSM), we correlated the extent of reported mucosal mast cell ([m]MC) infiltration of the upper and/or lower gastrointestinal tract (UGIT, n = 63; LGIT, n = 64; both, n = 57) with symptoms and markers of MC burden/subtype. GI symptoms were reported by all patients (mean 2.1 number of symptoms). A strong mMC infiltration was identified in 24 patients (UGIT, 17/63, 27%; LGIT, 19/64, 30%). Concurrent involvement of UGIT and LGIT (n = 12) correlated with female gender (75%) and a higher symptom burden (mean 2.7) but not with MC burden or subtype. Significant differences between non-AdvSM and AdvSM were reported regarding food intolerance (54% vs. 17%), cramping (54% vs. 22%) and weight loss (0% vs. 64%). KIT D816V was identified in 54/56 (96%) available biopsies. In 46 patients, digital PCR revealed a correlation with low albumin levels (r = - 0.270, P = 0.069) and the KIT D816V VAF in peripheral blood (r = 0.317, P = 0.036) but not with the extent of mMC infiltration or markers of MC burden/subtype. Although MC mediator triggered GI symptoms have a substantial impact on the quality of life, correlation to objective disease parameters is lacking thus making its systematic assessment challenging.
Topics: Humans; Female; Mastocytosis, Systemic; Quality of Life; Gastrointestinal Tract; Biopsy; Food Intolerance
PubMed: 38184670
DOI: 10.1038/s41598-023-49749-z -
Cirugia Pediatrica : Organo Oficial de... Jan 2024Cutis marmorata telangiectatica congenita (CMTC) is a rare capillary malformation characterized by persistent reticular and violaceous erythema. We present two cases of...
INTRODUCTION
Cutis marmorata telangiectatica congenita (CMTC) is a rare capillary malformation characterized by persistent reticular and violaceous erythema. We present two cases of CMTC.
CLINICAL OBSERVATION
The first case involved a 13-month-old male with a reticular violaceous macule on the left gluteal region and a brownish papule with Darier's sign on the inner malleolus of the left foot, which was biopsied, revealing > 15 mast cells per field, leading to a diagnosis of CMTC and solitary cutaneous mastocytoma. The second case involved a newborn with a characteristic CMTC lesion without other malformations at birth, who subsequently developed two cutaneous tumors consistent with infantile hemangiomas during follow-up.
DISCUSSION
CMTC is a benign condition. However, approximately 50% of cases exhibit associated anomalies. When CMTC is suspected, musculoskeletal, ophthalmological, and cutaneous malformations should be ruled out. To the best of our knowledge, this is the first report of CMTC associated with mastocytoma and one of the few cases associated with infantile hemangioma.
Topics: Infant, Newborn; Male; Humans; Infant; Biopsy; Livedo Reticularis; Mastocytoma
PubMed: 38180100
DOI: 10.54847/cp.2024.01.15 -
Leukemia Research Reports 2024Systemic mastocytosis is a rare hematologic malignancy that leads to the accumulation of neoplastic mast cells in the bone marrow, visceral organs, and skin. Mutations...
BACKGROUND
Systemic mastocytosis is a rare hematologic malignancy that leads to the accumulation of neoplastic mast cells in the bone marrow, visceral organs, and skin. Mutations in the receptor tyrosine kinase, KIT are seen in most patients with systemic mastocytosis. The most common mutation is a gain of function mutation in KIT D816V. Avapritinib is a highly selective KIT D816V inhibitor approved for the treatment of advanced systemic mastocytosis. Recent studies have also suggested that avapritinib is active across other KIT mutations located in exon 11 and exon 17.
CASE PRESENTATION
A 68 year old woman was referred for a history of lymphadenopathy and diarrhea and was ultimately found to have systemic mastocytosis with involvement in her bone marrow, gastrointestinal tract, liver, and spleen. The bone marrow biopsy reveled a novel KIT p.D816-N822delinsMIDSI mutation in exon 17. The patient was started on avapritinib leading to significant decrease in the frequency of her diarrhea and a significant reduction in her tryptase levels. Her course was complicated by arthralgias leading to a decrease in her avapritinib dose and ultimately a degranulation episode requiring hospitalization. Following dose re-escalation, patient has remained clinically stable without any further adverse events.
CONCLUSION
We report a case of aggressive systemic mastocytosis with a novel KIT mutation on exon 17 treated with avapritinib leading to a sustained response. While avapritinib is known as a potent inhibitor against the D816V mutation, our case suggests that it may also be effective against other rare KIT mutations in systemic mastocytosis offering more potential treatment options in patients with rare mutations.
PubMed: 38273969
DOI: 10.1016/j.lrr.2023.100409 -
The Journal of Allergy and Clinical... Oct 2023
Topics: Male; Humans; Child; Mastocytosis, Systemic; Spinal Fractures; Mastocytosis
PubMed: 37399946
DOI: 10.1016/j.jaip.2023.06.045