Cell communication systems based on polypeptide ligands use transmembrane receptors to transmit signals across the plasma membrane. In their biogenesis, receptors depend on the endoplasmic reticulum (ER)-Golgi system for folding, maturation, transport and localization to the cell surface. ER stress, caused by protein overproduction and misfolding, is a well-known pathology in neurodegeneration, cancer and numerous other diseases. How ER stress affects cell communication via transmembrane receptors is largely unknown. In disease models of multiple myeloma, chronic lymphocytic leukemia and osteogenesis imperfecta, we show that ER stress leads to loss of the mature transmembrane receptors FGFR3, ROR1, FGFR1, LRP6, FZD5 and PTH1R at the cell surface, resulting in impaired downstream signaling. This is caused by downregulation of receptor production and increased intracellular retention of immature receptor forms. Reduction of ER stress by treatment of cells with the chemical chaperone tauroursodeoxycholic acid or by expression of the chaperone protein BiP resulted in restoration of receptor maturation and signaling. We show a previously unappreciated pathological effect of ER stress; impaired cellular communication due to altered receptor processing. Our findings have implications for disease mechanisms related to ER stress and are particularly important when receptor-based pharmacological approaches are used for treatment.
- MeSH
- Endoplasmic Reticulum Chaperone BiP MeSH
- Taurochenodeoxycholic Acid pharmacology MeSH
- Humans MeSH
- Cell Line, Tumor MeSH
- Receptors, Cell Surface * metabolism MeSH
- Signal Transduction * drug effects MeSH
- Endoplasmic Reticulum Stress * drug effects MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
In chronic lymphocytic leukemia, the reliability of next-generation sequencing (NGS) to detect TP53 variants ≤10% allelic frequency (low-VAF) is debated. We tested the ability to detect 23 such variants in 41 different laboratories using their NGS method of choice. The sensitivity was 85.6%, 94.5%, and 94.8% at 1%, 2%, and 3% VAF cut-off, respectively. While only one false positive (FP) result was reported at >2% VAF, it was more challenging to distinguish true variants <2% VAF from background noise (37 FPs reported by 9 laboratories). The impact of low-VAF variants on time-to-second-treatment (TTST) and overall survival (OS) was investigated in a series of 1092 patients. Among patients not treated with targeted agents, patients with low-VAF TP53 variants had shorter TTST and OS versus wt-TP53 patients, and the relative risk of second-line treatment or death increased continuously with increasing VAF. Targeted therapy in ≥2 line diminished the difference in OS between patients with low-VAF TP53 variants and wt-TP53 patients, while patients with high-VAF TP53 variants had inferior OS compared to wild type-TP53 cases. Altogether, NGS-based approaches are technically capable of detecting low-VAF variants. No strict threshold can be suggested from a technical standpoint, laboratories reporting TP53 mutations should participate in a standardized validation set-up. Finally, whereas low-VAF variants affected outcomes in patients receiving chemoimmunotherapy, their impact on those treated with novel therapies remains undetermined. Our results pave the way for the harmonized and accurate TP53 assessment, which is indispensable for elucidating the role of TP53 mutations in targeted treatment.
- Publication type
- Journal Article MeSH
Expression of CD2, CD25 and/or CD30 in extracutaneous mast cells (MC) is a minor diagnostic criterion for systemic mastocytosis (SM) in the classification of the World Health Organization and International Consensus Classification. So far, it remains unknown whether expression of these antigens on MC is of prognostic significance in SM. We performed a retrospective multi-center study of patients with SM using the data set of the registry of the European Competence Network on Mastocytosis, including 5034 patients with various MC disorders. The percentage of CD2-, CD25+ and/or CD30+ MC was considerably lower in patients with indolent SM compared to patients with advanced SM, including aggressive SM and MC leukemia. Whereas CD25 and CD30 expression in MC could not be associated with prognosis, we found that lack of CD2 expression in MC is associated with a significantly reduced overall survival (OS) in patients with SM (p < 0.0001). Lack of CD2 was also associated with the presence of extramedullary involvement affecting the spleen, liver, and/or lymph nodes (odds ratio 2.63 compared to SM with CD2+ MC). Together, lack of CD2 expression in MC is a prognostic marker and indicator of reduced OS and extramedullary disease expansion in patients with SM.
- MeSH
- Ki-1 Antigen * metabolism MeSH
- CD2 Antigens * metabolism MeSH
- Child MeSH
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Mast Cells * metabolism pathology immunology MeSH
- Adolescent MeSH
- Young Adult MeSH
- Prognosis MeSH
- Interleukin-2 Receptor alpha Subunit * metabolism MeSH
- Registries * MeSH
- Retrospective Studies MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Mastocytosis, Systemic * metabolism pathology mortality diagnosis MeSH
- Check Tag
- Child MeSH
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Adolescent MeSH
- Young Adult MeSH
- Male MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Multicenter Study MeSH
- Geographicals
- Europe MeSH
BACKGROUND: Chronic lymphocytic leukemia (CLL) is a common adult leukemia characterized by the accumulation of neoplastic mature B cells in blood, bone marrow, lymph nodes, and spleen. The disease biology remains unresolved in many aspects, including the processes underlying the disease progression and relapses. However, studying CLL in vitro poses a considerable challenge due to its complexity and dependency on the microenvironment. Several approaches are utilized to overcome this issue, such as co-culture of CLL cells with other cell types, supplementing culture media with growth factors, or setting up a three-dimensional (3D) culture. Previous studies have shown that 3D cultures, compared to conventional ones, can lead to enhanced cell survival and altered gene expression. 3D cultures can also give valuable information while testing treatment response in vitro since they mimic the cell spatial organization more accurately than conventional culture. METHODS: In our study, we investigated the behavior of CLL cells in two types of material: (i) solid porous collagen scaffolds and (ii) gel composed of carboxymethyl cellulose and polyethylene glycol (CMC-PEG). We studied CLL cells' distribution, morphology, and viability in these materials by a transmitted-light and confocal microscopy. We also measured the metabolic activity of cultured cells. Additionally, the expression levels of MYC, VCAM1, MCL1, CXCR4, and CCL4 genes in CLL cells were studied by qPCR to observe whether our novel culture approaches lead to increased adhesion, lower apoptotic rates, or activation of cell signaling in relation to the enhanced contact with co-cultured cells. RESULTS: Both materials were biocompatible, translucent, and permeable, as assessed by metabolic assays, cell staining, and microscopy. While collagen scaffolds featured easy manipulation, washability, transferability, and biodegradability, CMC-PEG was advantageous for its easy preparation process and low variability in the number of accommodated cells. Both materials promoted cell-to-cell and cell-to-matrix interactions due to the scaffold structure and generation of cell aggregates. The metabolic activity of CLL cells cultured in CMC-PEG gel was similar to or higher than in conventional culture. Compared to the conventional culture, there was (i) a lower expression of VCAM1 in both materials, (ii) a higher expression of CCL4 in collagen scaffolds, and (iii) a lower expression of CXCR4 and MCL1 (transcript variant 2) in collagen scaffolds, while it was higher in a CMC-PEG gel. Hence, culture in the material can suppress the expression of a pro-apoptotic gene (MCL1 in collagen scaffolds) or replicate certain gene expression patterns attributed to CLL cells in lymphoid organs (low CXCR4, high CCL4 in collagen scaffolds) or blood (high CXCR4 in CMC-PEG).
- MeSH
- Cell Culture Techniques methods MeSH
- Leukemia, Lymphocytic, Chronic, B-Cell * pathology metabolism MeSH
- Gels chemistry MeSH
- Collagen * chemistry pharmacology MeSH
- Humans MeSH
- Polyethylene Glycols * chemistry MeSH
- Receptors, CXCR4 metabolism MeSH
- Carboxymethylcellulose Sodium * chemistry pharmacology MeSH
- Cell Culture Techniques, Three Dimensional methods MeSH
- Tissue Scaffolds * chemistry MeSH
- Cell Survival drug effects MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
Large-scale next-generation sequencing (NGS) studies revealed extensive genetic heterogeneity, driving a highly variable clinical course of chronic lymphocytic leukaemia (CLL). The evolution of subclonal populations contributes to diverse therapy responses and disease refractoriness. Besides, the dynamics and impact of subpopulations before therapy initiation are not well understood. We examined changes in genomic defects in serial samples of 100 untreated CLL patients, spanning from indolent to aggressive disease. A comprehensive NGS panel LYNX, which provides targeted mutational analysis and genome-wide chromosomal defect assessment, was employed. We observed dynamic changes in the composition and/or proportion of genomic aberrations in most patients (62%). Clonal evolution of gene variants prevailed over the chromosomal alterations. Unsupervised clustering based on aberration dynamics revealed four groups of patients with different clinical behaviour. An adverse cluster was associated with fast progression and early therapy need, characterized by the expansion of TP53 defects, ATM mutations, and 18p- alongside dynamic SF3B1 mutations. Our results show that clonal evolution is active even without therapy pressure and that repeated genetic testing can be clinically relevant during long-term patient monitoring. Moreover, integrative NGS testing contributes to the consolidated evaluation of results and accurate assessment of individual patient prognosis.
Východiska: Idiopatická retroperitoneální fibróza je charakterizovaná rozvojem periaortických a periiliakálních zánětlivých infiltrátů s výraznou fibrózou. Léčba rituximabem v kombinaci s glukokortikoidy je účinná, ale léčebné odpovědi nejsou dlouhodobé. U jiných nemocí byly srovnávány léčebné odpovědi dosahované dvojkombinací rituximab a glukokortikoidy s trojkombinací rituximab, cyklofosfamid a dexametazon, která dosáhla vždy delší a hlubší léčebné odpovědi. A proto jsme ji aplikovali i zde. Případ: Muž, 56 let, přišel s CT obrazem retroperitonální fibrózy s unilaterální okluzí ureteru. Biopsie ložiska prokázala retroperitoneální fibrózu s histologickým nálezem onemocnění asociovaného s IgG4. Léčba prednizonem v dávce 1 mg/kg byla špatně tolerována. Proto byla změněna na trojkombinaci rituximabu 375 mg/m2 v den 1., cyklofosfamidu 300 mg/m2 v infuzi v den 1. a 15. a dexametazonu 20 mg v infuzi v den 1. a 15. v 28denním cyklu. Výsledky: Vyšetření pozitronovou emisní tomografií (PET/CT) s fluorodeoxyglukózou (FDG) po 4. měsíci léčby prokazovalo výrazný pokles akumulace FDG a vymizení fibrotické masy. Léčba trvala 8 měsíců a na ni navázala udržovací léčba, rituximab 1 000 mg a dexametazon 20 mg v 6měsíčních intervalech. Při PET/MR kontrole po 3 letech od zahájení léčby trvá vymizení dříve patrné fibrotické masy (kompletní remise). S aktivitou nemoci koreloval počet cirkulujících plazmablastů v periferní krvi. Závěr: Léčba retroperitonální fibrózy kombinací rituximabu, cyklofosfamidu a dexametazonu dosahuje velmi rychle vymizení patologické akumulace FDG a fibrotické retroperitonální masy již po 4 měsících léčby. Kontrolní PET/MR zobrazení po 3 letech od zahájení léčby potvrdilo kompletní remisi nemoci s vymizením patologické akumulace FDG a s kompletním vymizením dříve zřetelných fibrotických mas. Stále je ale nutná udržovací léčba rituximabem, jak lze odvodit z vzestupu počtu cirkulujích plazmablastů při prodloužení intervalu mezi aplikací rituximabu.
Background: Idiopathic retroperitoneal fibrosis is characterized by the development of inflammatory infiltrates with marked fibrosis along the large retroperitoneal vessels. Rituximab in combination with glucocorticoids constitute an effective therapy, but the responses are not long-lasting. In other similar situations, addition of cyclophosphamide to the combination achieved longer and deeper responses. This was the reason to use the triple combination in this case. Case: A 56-year-old man came with four weeks lasting abdominal pain with CT finding of retroperitoneal fibrosis with unilateral ureteral occlusion. Biopsy confirmed retroperitoneal fibrosis with histological findings of IgG4-associated disease. Treatment with prednizone was poorly tolerated. Therefore, the patient was switched to the combination of rituximab 375 mg/m2 on day 1, cyclophosphamide 300 mg/m2 in infusion in days 1 and 15, plus dexamethasone 20 mg in infusion on days 1 and 15, repeated in a 28-day cycle. Results: Fluorodeoxyglucose (FDG) positron emission tomography (PET/CT) examination after 4 months of treatment showed a marked decrease in FDG accumulation and complete disappearance of the fibrotic mass. After 8 months, the induction therapy was followed by maintenance therapy with rituximab 1,000 mg plus dexamethasone 20 mg in 6-month intervals. Control PET/MR examination after 3 years is consistent with complete remission. The number of circulating plasmablasts correlated with the disease activity. Conclusion: Treatment of retroperitoneal fibrosis with the tripple combination of rituximab, cyclophosphamide and dexamethasone achieved a very rapid disappearance of pathological FDG accumulation and fibrotic retroperitoneal mass, with complete disappearance achieved after 4 months of treatment. After 3 years of maitenance therapy, the diesease is still in complete remission on PET/MR examination. We suggest to continue the maintenance therapy with rituximab because of some increase in the number of circulating plasmablasts after prolongation of the intervals between rituximab administration.
- MeSH
- Cyclophosphamide administration & dosage pharmacology therapeutic use MeSH
- Dexamethasone administration & dosage pharmacology therapeutic use MeSH
- Fluorodeoxyglucose F18 pharmacology therapeutic use MeSH
- Drug Therapy, Combination * methods MeSH
- Middle Aged MeSH
- Humans MeSH
- Positron Emission Tomography Computed Tomography methods MeSH
- Retroperitoneal Fibrosis * diagnostic imaging diagnosis drug therapy MeSH
- Rituximab pharmacology therapeutic use MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Publication type
- Case Reports MeSH
- Research Support, Non-U.S. Gov't MeSH
Bruton tyrosine kinase (BTK) inhibitor therapy induces peripheral blood lymphocytosis in chronic lymphocytic leukemia (CLL), which lasts for several months. It remains unclear whether nongenetic adaptation mechanisms exist, allowing CLL cells' survival during BTK inhibitor-induced lymphocytosis and/or playing a role in therapy resistance. We show that in approximately 70% of CLL cases, ibrutinib treatment in vivo increases Akt activity above pretherapy levels within several weeks, leading to compensatory CLL cell survival and a more prominent lymphocytosis on therapy. Ibrutinib-induced Akt phosphorylation (pAktS473) is caused by the upregulation of Forkhead box protein O1 (FoxO1) transcription factor, which induces expression of Rictor, an assembly protein for the mTORC2 protein complex that directly phosphorylates Akt at serine 473 (S473). Knockout or inhibition of FoxO1 or Rictor led to a dramatic decrease in Akt phosphorylation and growth disadvantage for malignant B cells in the presence of ibrutinib (or PI3K inhibitor idelalisib) in vitro and in vivo. The FoxO1/Rictor/pAktS473 axis represents an early nongenetic adaptation to B cell receptor (BCR) inhibitor therapy not requiring PI3Kδ or BTK kinase activity. We further demonstrate that FoxO1 can be targeted therapeutically and its inhibition induces CLL cells' apoptosis alone or in combination with BTK inhibitors (ibrutinib, acalabrutinib, pirtobrutinib) and blocks their proliferation triggered by T cell factors (CD40L, IL-4, and IL-21).
- MeSH
- Adenine * analogs & derivatives pharmacology MeSH
- Leukemia, Lymphocytic, Chronic, B-Cell * drug therapy metabolism genetics pathology MeSH
- Forkhead Box Protein O1 * metabolism genetics MeSH
- Phosphorylation MeSH
- Humans MeSH
- Mice MeSH
- Cell Line, Tumor MeSH
- Neoplasm Proteins metabolism genetics MeSH
- Piperidines * pharmacology MeSH
- Rapamycin-Insensitive Companion of mTOR Protein * genetics metabolism MeSH
- Agammaglobulinaemia Tyrosine Kinase metabolism genetics antagonists & inhibitors MeSH
- Proto-Oncogene Proteins c-akt * metabolism genetics MeSH
- Pyrazoles * pharmacology MeSH
- Pyrimidines * pharmacology MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
PURPOSE: The use of inotuzumab ozogamicin (InO), a conjugated anti-CD22 monoclonal antibody, is becoming a promising frontline treatment for older patients with ALL. PATIENTS AND METHODS: EWALL-INO is an open-label prospective multicenter phase II trial (ClinicalTrials.gov identifier: NCT03249870). Patients age 55 years and older with newly diagnosed CD22+ Philadelphia chromosome-negative (Ph-) B-cell precursor (BCP) ALL were eligible. After a prephase, a first induction consisting of vincristine, dexamethasone, and three injections of InO (0.8 mg/m2 day 1, 0.5 mg/m2 day 8/day 15) was followed by a second induction combining cyclophosphamide, dexamethasone, and two injections of InO (0.5 mg/m2 day 1/day 8). Responders received up to six cycles of chemotherapy consolidation and 18-month chemotherapy maintenance. Allotransplant was allowed after three consolidations. The primary end point was 1-year overall survival (OS). RESULTS: Between December 2017 and March 2022, 131 patients (median age 68 years) were included. Three patients died during induction 1 (n = 130), two from multiple organ failure and one from hemorrhage, and none during induction 2 (n = 120). After induction 2, 90% of the patients achieved complete remission (CR) or CR with incomplete platelet recovery (CRp) and 80% had measurable residual disease (MRD2) <10-4. Among responders (n = 119), 47 relapsed and 14 died in CR/CRp. One-year OS, relapse-free survival (RFS), and cumulative incidence of relapse (CIR) rates were 73.2%, 66%, and 25%, respectively. High-risk cytogenetics and lower CD22 expression (<70%) were associated with worse OS, while both high-risk cytogenetics and MRD2 ≥10-4 were associated with lower RFS and higher CIR. The 10 allotransplanted patients had very favorable outcomes (90% 2-year OS/RFS and no relapse). Only one nonfatal sinusoidal obstructive syndrome was documented during the study. CONCLUSION: Our results support InO's use in first-line regimens for older patients with CD22+ Ph- BCP-ALL.
- MeSH
- Sialic Acid Binding Ig-like Lectin 2 * MeSH
- Cyclophosphamide administration & dosage therapeutic use MeSH
- Dexamethasone administration & dosage therapeutic use MeSH
- Philadelphia Chromosome MeSH
- Inotuzumab Ozogamicin * therapeutic use MeSH
- Middle Aged MeSH
- Humans MeSH
- Precursor B-Cell Lymphoblastic Leukemia-Lymphoma * drug therapy mortality genetics MeSH
- Prospective Studies MeSH
- Antineoplastic Combined Chemotherapy Protocols * therapeutic use MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Vincristine administration & dosage therapeutic use MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Clinical Trial, Phase II MeSH
- Multicenter Study MeSH
Závěrečná zpráva o řešení grantu Agentury pro zdravotnický výzkum MZ ČR
nestr.
Familiární onemocnění krvetvorby (FHD) jsou vzácnou a heterogenní skupinou onemocnění. Variabilní klinické projevy a prolínající se formy FHD zapříčiňují mnohy nesprávné stanovení diagnózy. Díky moderním genomickým přístupům (celoexomové sekvenování) dnes dokážeme vyřešit mnohé dosud neobjasněné případy. Nicméně u některých pacientů detekujeme jedinečnou a rodinně-specifickou genetickou variantu nejasného klinického významu (VUS). Cílem navrhované studie je vyhledávat zárodečné varianty u postižených rodin s FHD. Dále budeme zjišťovat funkční dopad identifikovaných VUS, abychom potvrdili jejich kauzalitu pomocí in vitro modelů (CRISPR/Cas9, mikroskopické a proteomické eseje). Na základě těchto zkušeností plánujeme zavést nový biomedicínský postup funkčního testování VUS do rutinní laboratorní praxe. Stanovení správné diagnózy u pacienta je zásadní i z důvodů určení rizika výskytu onkologických malignit, ke kterým některé zárodečné varianty predisponují. Očekáváme přímý dopad naší studie do translačního výzkumu hematopoézy, karcinogenézy a genové terapie.; Familial haematopoietic disorders (FHD) are a rare and heterogeneous group of disorders. Variable clinical expressivity and overlapping forms of FDH cause many misdiagnoses. Thanks to modern genomic approaches (whole exome sequencing), we are able to solve many previously unclear cases today. However, in some patients we detect a unique and family-specific gene variant of uncertain significance (VUS). The aim of the proposed study is to search for germline variants in affected families with FHD phenotype. Furthermore, we plan to investigate the functional impact of identified VUSs to verify their causality using in vitro models (CRISPR/Cas9, microscopic, and proteomic assays). Based on these experiences, we will introduce new biomedical pipeline for functional testing of VUSs into routine laboratory practice. Determining the correct diagnosis of a patient is also essential to define the risk of cancer, which some germline variants predispose. We expect a direct impact of our study in translational research of haematopoiesis, cancerogenesis and gene therapy.
