Majeed syndrome is an autosomal recessive disorder characterised by the triad of chronic recurrent multifocal osteomyelitis, congenital dyserythropoietic anaemia and a neutrophilic dermatosis that is ...caused by mutations in LPIN2. Long-term outcome is poor. This is the first report detailing the treatment of Majeed syndrome with biological agents and demonstrates clinical improvement with IL-1blockade.
We describe the clinical presentation, genetic analysis, cytokine profiles and response to biological therapy in two brothers with Majeed syndrome.
Both boys were homozygous for a novel 2-base pair deletion in LPIN2 (c.1312_1313delCT; p.Leu438fs+16X), confirming the diagnosis. Their bone disease and anaemia were refractory to treatment with corticosteroids. Both siblings had elevated proinflammatory cytokines in their serum, including tumour necrosis factor α (TNF-α), however a trial of the TNF inhibitor etanercept resulted in no improvement. IL-1 inhibition with either a recombinant IL-1 receptor antagonist (anakinra) or an anti-IL-1β antibody (canakinumab) resulted in dramatic clinical and laboratory improvement.
The differential response to treatment with TNF-α or IL-1 blocking agents sheds light into disease pathogenesis; it supports the hypothesis that Majeed syndrome is an IL-1β dependent autoinflammatory disorder, and further underscores the importance of IL-1 in sterile bone inflammation.
Background
The hallmark of myelodysplastic syndrome (MDS) remains dysplasia in the bone marrow (BM). However, diagnosing MDS may be challenging and subject to inter‐observer variability. Thus, there ...is an unmet need for novel objective, standardized and reproducible methods for evaluating dysplasia. Imaging flow cytometry (IFC) offers combined analyses of phenotypic and image‐based morphometric parameters, for example, cell size and nuclearity. Hence, we hypothesized IFC to be a useful tool in MDS diagnostics.
Methods
Using a different‐from‐normal approach, we investigated dyserythropoiesis by quantifying morphometric features in a median of 5953 erythroblasts (range: 489–68,503) from 14 MDS patients, 11 healthy donors, 6 non‐MDS controls with increased erythropoiesis, and 6 patients with cytopenia.
Results
First, we morphometrically confirmed normal erythroid maturation, as immunophenotypically defined erythroid precursors could be sequenced by significantly decreasing cell‐, nuclear‐ and cytoplasm area. In MDS samples, we demonstrated cell size enlargement and increased fractions of macronormoblasts in late‐stage erythroblasts (both p < .0001). Interestingly, cytopenic controls with high‐risk mutational patterns displayed highly aberrant cell size morphometrics. Furthermore, assisted by machine learning algorithms, we reliably identified and enumerated true binucleated erythroblasts at a significantly higher frequency in two out of three erythroblast maturation stages in MDS patients compared to normal BM (both p = .0001).
Conclusion
We demonstrate proof‐of‐concept results of the applicability of automated IFC‐based techniques to study and quantify morphometric changes in dyserythropoietic BM cells. We propose that IFC holds great promise as a powerful and objective tool in the complex setting of MDS diagnostics with the potential for minimizing inter‐observer variability.
Summary
Evidence of distinct disease propagating stem cells in myelodysplastic syndrome (MDS) has emerged in recent years. However, immunophenotypic characterization of these cancer stem cells ...remains sparse. In acute myeloid leukaemia (AML), we have previously described aberrant expression of the C‐type lectin domain family 12, member A (CLEC12A) as a stable and reliable marker of leukaemia blasts and as a tool for assessing minimal residual disease. Furthermore, CLEC12A has been proposed as a promising marker of leukaemic stem cells in AML. The role of CLEC12A in MDS, however, remains to be elucidated. In this study, we found CLEC12A aberrantly expressed on the CD34+CD38− cell compartment in 71% (22/31) of MDS patients, distributed across all Revised International Prognostic Scoring System risk groups. We showed that the CD34+CD38−CLEC12A+ cells were indeed malignant and possessed functional stem cell properties in the long‐term colony‐initiating cell assay. As opposed to reported findings in AML, we showed that cancer stem cells from MDS samples derived from both CLEC12A positive and negative CD34+CD38− subpopulations. Due to the absence of CLEC12A on normal haematopoietic stem cells, CLEC12A stem cell immunophenotyping may contribute to diagnosing and monitoring MDS patients and could furthermore add knowledge about disease propagating cells in MDS.
GATA-2 deficiency was recently described as common cause of overlapping syndromes of immunodeficiency, lymphedema, familiar myelodysplastic syndrome or acute myeloid leukemia. The aim of our study ...was to analyze bone marrow and peripheral blood samples of children with myelodysplastic syndrome or aplastic anemia to define prevalence of the GATA2 mutation and to assess whether mutations in GATA-2 transcription factor exhibit specific immunophenotypic features. The prevalence of a GATA2 mutation in a consecutively diagnosed cohort of children was 14% in advanced forms of myelodysplastic syndrome (refractory anemia with excess blasts, refractory anemia with excess blasts in transformation, and myelodysplasia-related acute myeloid leukemia), 17% in refractory cytopenia of childhood, and 0% in aplastic anemia. In GATA-2-deficient cases, we found the most profound B-cell lymphopenia, including its progenitors in blood and bone marrow, which correlated with significantly diminished intronRSS-Kde recombination excision circles in comparison to other myelodysplastic syndrome/aplastic anemia cases. The other typical features of GATA-2 deficiency (monocytopenia and natural killer cell lymphopenia) were less discriminative. In conclusion, we suggest screening for GATA2 mutations in pediatric myelodysplastic syndrome, preferentially in patients with impaired B-cell homeostasis in bone marrow and peripheral blood (low number of progenitors, intronRSS-Kde recombination excision circles and naïve cells).
Acute erythroid leukemia was diagnosed in a 4-month-old boy. Cytogenetic analysis of bone marrow (BM) cells showed a t(11;20)(p11;q11) translocation. RNA extracted from the BM was sequenced and ...analyzed for fusion transcripts using the software FusionMap. A ZMYND8-RELA fusion was ranked first. RT-PCR and direct sequencing verified the presence of an in frame ZMYND8-RELA chimeric transcript. Fluorescence in situ hybridization showed that the ZMYND8-RELA was located on the p12 band of der(11); therefore a cytogenetically invisible pericentric inversion in chromosome 11 must have taken place besides the translocation. The putative ZMYND8-RELA fusion protein contains the Zinc-PHD finger domain, a bromodomain, a PWWP domain, a MYND type of zinc finger of ZMYND8, and the entire RELA protein, indicating that it might act leukemogenically by influencing several cellular processes including the NF-kappa-B pathway.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Several laboratories have shown that cells with a memory B-cell phenotype can have the same clonotype as multiple myeloma tumor cells.
The aim of this study was to determine whether some memory B ...cells have the same genetic alterations as their corresponding multiple myeloma malignant plasma cells. The methodology included sorting multiple myeloma or memory B cells into RNA stabilizing medium for generation of subset-specific polymerase chain reaction complementary DNA libraries from one or 100 cells.
Cells with the phenotype of tumor plasma cells (CD38(++)CD19(-)CD45(-/+)CD56(-/+/++)) or memory B cells (CD38(-)/CD19(+)/CD27(+)) were isolated by flow activated cell sorting. In samples from all four patients with multiple myeloma and from two of the three with monoclonal gammopathy of undetermined significance, we identified memory B cells expressing multiple myeloma-specific oncogenes (FGFR3; IGH-MMSET; CCND1 high) dysregulated by an IGH translocation in the respective tumor plasma cells. By contrast, in seven patients with multiple myeloma, each of whom had tumor plasma cells with a K-RAS61 mutation, a total of 32,400 memory B cells were analyzed using a sensitive allele-specific, competitive blocker polymerase chain reaction assay, but no K-RAS mutations were identified.
The increased expression of a specific "early" oncogene of multiple myeloma (monoclonal gammopathy of undetermined significance) in some memory B cells suggests that dysregulation of the oncogene occurs in a precursor B-cell that can generate memory B cells and transformed plasma cells. However, if memory B cells lack "late" oncogene (K-RAS) mutations but express the "early" oncogene, they cannot be involved in maintaining the multiple myeloma tumor, but presumably represent a clonotypic remnant that is only partially transformed.
To identify cytogenetic risk factors predicting outcome in children with advanced myelodysplastic syndrome, overall survival of 192 children prospectively enrolled in European Working Group of ...Myelodysplastic Syndrome in Childhood studies was evaluated with regard to karyotypic complexity. Structurally complex constitutes a new definition of complex karyotype characterized by more than or equal to 3 chromosomal aberrations, including at least one structural aberration. Five-year overall survival in patients with more than or equal to 3 clonal aberrations, which were not structurally complex, did not differ from that observed in patients with normal karyotype. Cox regression analysis revealed the presence of a monosomal and structurally complex karyotype to be strongly associated with poor prognosis (hazard ratio = 4.6, P < .01). Notably, a structurally complex karyotype without a monosomy was associated with a very short 2-year overall survival probability of only 14% (hazard ratio = 14.5; P < .01). The presence of a structurally complex karyotype was the strongest independent prognostic marker predicting poor outcome in children with advanced myelodysplastic syndrome.
An association between hepatitis and aplastic anemia (AA) is known as hepatitis-associated AA, and is characterized by an acute attack of hepatitis followed by the development of AA. We report 2 ...clinical cases of acute seronegative hepatitis in which pancytopenia with mild dysplasia developed after 3 months; however, neither of our cases fulfilled the histological criteria of AA, but rather myelodysplastic syndrome. This novel association bears considerable resemblance to hepatitis-associated AA, and raises the question of whether hepatitis-associated dysmyelopoiesis should be included in the spectrum of hypocellular myelodysplastic syndrome.
Therapy-related myeloid neoplasms (tMN) develop after exposure to cytotoxic and radiation therapy, and due to their adverse prognosis, it is of paramount interest to identify patients at high risk. ...The presence of clonal hematopoiesis has been shown to increase the risk of developing tMN. The value of analyzing hematopoietic stem cells harvested at leukapheresis before autologous stem cell transplantation (ASCT) with next-generation sequencing and immunophenotyping represents potentially informative parameters that have yet to be discovered. We performed a nested case-control study to elucidate the association between clonal hematopoiesis, mobilization potential, and aberrant immunophenotype in leukapheresis products with the development of tMN after ASCT. A total of 36 patients with nonmyeloid disease who were diagnosed with tMN after treatment with ASCT were included as case subjects. Case subjects were identified from a cohort of 1130 patients treated with ASCT and matched with 36 control subjects who did not develop tMN after ASCT. Case subjects were significantly poorer mobilizers of CD34+ cells at leukapheresis (P = .016), indicating that these patients possess inferior bone marrow function. Both clonal hematopoiesis (odds ratio, 5.9; 95% confidence interval, 1.8-19.1; P = .003) and aberrant expression of CD7 (odds ratio, 6.6; 95% confidence interval, 1.6-26.2; P = .004) at the time of ASCT were associated with an increased risk of developing tMN after ASCT. In conclusion, clonal hematopoiesis, present at low variant allele frequencies, and aberrant CD7 expression on stem cells in leukapheresis products from patients with nonmyeloid hematologic cancer hold potential for the early identification of patients at high risk of developing tMN after ASCT.
•Low variant allele frequency clonal hematopoiesis or aberrant CD7 expression on hematopoietic stem cells increases the risk of tMN.•Patients at high risk of developing tMN after ASCT can be identified at the time of leukapheresis.
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Childhood myelodysplastic syndromes (MDS) belong to a rare group of disorders of aberrant clonal hematopoiesis manifesting throughout entire childhood and adolescence. We had previously established ...that GATA2 germline mutations can be considered the most common "first hit" in pediatric MDS seen in 7% of primary MDS. However the secondary somatic aberrations facilitating leukemogenesis are not elucidated in children. Previous sequencing efforts established that most somatic mutations very frequently encountered in adults, i.e. affecting TET2, DNMT3a, and the spliceosome genes, do not play a role in the pathogenesis of childhood MDS. Here we aim to define the global mutational landscape in childhood MDS using targeted next-generation sequencing (NGS) approaches.
We investigated children and adolescents enrolled in the prospective studies of the European Working Group of Childhood MDS. Diverse target enrichment and NGS strategies were established including hybridization capture and Ampliseq PCR, Illumina Miseq/Hiseq and Iontorrent PGM. We first examined a pilot cohort of 68 patients for mutations in 138 myeloid leukemia genes. This allowed for the identification of recurrently mutated genes that were selected to be included in a pediatric MDS panel encompassing 28 genes. Targeted NGS using the Iontorrent PGM identified known recurrent mutations. However, the high indel error rate and coverage gaps in homopolymeric regions i.e. in ASXL1 precluded further studies. Using inhouse-adapted Ampliseq-Miseq approach we then sequenced DNA from bone marrow of 586 MDS patients (469 primary and 117 secondary MDS after radio/chemotherapy or inherited bone marrow failure syndromes) at an average depth exceeding 700 reads per amplicon. Somatic mutations were identified in 22% of primary MDS patients, with 1, 2 and 3 genes affected in 16%, 4.5%, and 1.5% of cases, respectively. In secondary MDS twice as many patients (46%) carried mutations; 1, 2, and 3 genes were concurrently mutated in 32.5%, 9.5%, and 4% of patients, respectively. Longitudinal NGS analyses and single CFU colony sequencing confirmed the presence of multiple somatic clones evolving in a hierarchical manner throughout disease course. Most frequent mutations identified in more than 1% of our study cohort of primary MDS were: SETBP1 (7%), ASXL1 (6%), NRAS/KRAS (5%), RUNX1 (3%), PTPN11 (3%) and BCOR/BCORL (1.5%); and in secondary MDS: RUNX1 (14.5%), TP53 (9%), NRAS/KRAS (8.5%), ASXL1 (8%), SETBP1 (6%), PTPN11 (6%), CBL (5%), BCOR/BCORL1 (3.4%). Other genes mutated at very low frequency of <1% were CTCF, STAG2, RAD21, PTEN, JAK3, FLT3, CSF3R, and EZH2. No somatic mutations were identified in CEBPA, GATA1, GATA2, JAK2, cKIT, VPS45, MPL, CALR, SH2B3. The analysis of individual mutational clusters established that for some mutations strongly associate with monosomy 7; i.e. this cytogenetic subgroup was prevalent in 100% of EZH2, 90% of SETBP1, 79% of RUNX1, and 74% of ASXL1 - mutated children with MDS
In conclusion, we established and cross-platform validated a targeted NGS-panel for pediatric MDS, allowing to identify clonal mutations at a sensitivity of at least 10%. In this, to our knowledge largest systematicaly studied cohort of children with MDS we show that mutational load and clonal complexity differs between primary and secondary MDS, and maintains specific patterns for monosomy 7. Although the biological significance of these genomic changes is currently not understood, the emerging distinctive patterns may already be helpful in establishing therapeutic subgroups.
No relevant conflicts of interest to declare.
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