Hemato, Volume 2, Issue 3 (September 2021) – 15 articles

In vitro culture is widely used for characterization of primary human acute myeloid leukemia (AML) cells, but even when using optimized handling and culture conditions the AML cells show spontaneous in vitro apoptosis with a gradual decrease in cell viability during culture. The extent of this stress-induced apoptosis varies between patients, and a high degree of apoptosis is associated with high pre-culture BCL2 levels together with low levels of BAX and Heat Shock Proteins 30 and 90. We compared the global proteomic profiles during ongoing in vitro apoptosis for patients with high and low AML cell viability (i.e., less extensive versus extensive spontaneous apoptosis) after 48 h of culture. We identified 7902 proteins, but only 276 proteins differed significantly between patients with high (i.e., >25% viable cells; 192 upregulated and 84 downregulated peptides) and low viability after in vitro culture. Protein interaction network analysis based on these 276 protein identified three protein networks that included 18 proteins; most of these proteins were localized to the endoplasmic reticulum and several of them are involved in or are altered during the process of endoplasmic reticulum stress/unfolded protein stress response. To conclude, primary AML cells are heterogeneous with regard to degree of apoptosis in response to cellular stress, and this difference in regulation of apoptosis is associated with differences in the induction of and/or response to the unfolded protein stress response. Full article

To clarify the prognostic value of 2-[¹⁸F]fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) in Neurolymphomatosis (NL), we retrospectively reviewed medical records of all NL patients who had undergone ¹⁸F-FDG PET/CT from 2007 to 2020 at Kameda Medical Center and Tokyo Medical and Dental University Hospital. The clinical data of patients were compared with ¹⁸F-FDG PET/CT findings of number of nerve lesions and presence of non-nerve extranodal lesions (ENL). Subsequently, we calculated recurrence-free survival (RFS) and overall survival (OS) using the Kaplan–Meier method. A total of 28 patients (mean age 70.1 years, range 44–87 years; 15 women) were included in the study and 7 patients (25.0%) relapsed NL. The number of nerve lesions detected by ¹⁸F-FDG PET/CT ranged from 1 to 5, with an average of 2.02. ENL was observed in 18 cases (64.3%). The comparison between the findings revealed that the more the lesions detected by ¹⁸F-FDG PET/CT, the higher the probability of recurrence (χ² = 13.651, p = 0.0085) and there was significantly shorter RFS for the patients with 3 or more nerve lesions (p = 0.0059), whereas the presence of ENL was not significantly associated with any clinical findings. The present study revealed that the more nerve lesions detected by ¹⁸F-FDG PET/CT, the poorer the recurrence rate and RFS. Full article

Anaplastic large cell lymphoma (ALCL) is a histological subtype of non-Hodgkin lymphoma, largely characterized by anaplastic lymphoma kinase (ALK) positivity, resulting from the chromosomal translocation t(2;5). We report a pediatric case of ALK-positive ALCL with primary concomitant involvement of bone and central nervous system (CNS); thereafter, a literature review about pediatric primary bone and primary CNS ALCL was conducted. According to the analyzed data, our case is unique because it is characterized by the contemporary involvement of the spine and CNS. During and after chemotherapy, our patient was monitored by detecting minimal residual disease (MRD) through the analysis of fusion transcript nucleophosmin-ALK. MRD assessment, not only in bone marrow but also in peripheral blood, seems to be a very powerful tool for predicting the prognosis of pediatric ALCL patients, as already described in the literature. Moreover, as shown in our case, it could be used during the follow-up for early recognition of relapse. Full article

Plasmacytoid dendritic cells (PDC) constitute a small subset of normal bone marrow (BM) cells but have also been shown to be present, sometimes in large numbers, in several hematological malignancies such as acute myeloid leukemia with RUNX1 mutation, chronic myelomonocytic leukemia or, obviously, blastic plasmacytoid dendritic cell neoplasms. These cells have been reported to display somewhat variable immunophenotypic features in different conditions. However, little is known of their plasticity within individual patients. Using an unsupervised clustering tool (FlowSOM) to re-visit flow cytometry results of seven previously analyzed cases of hematological malignancies (6 acute myeloid leukemia and one chronic myelomonocytic leukemia) with a PDC contingent, we report here on the unexpectedly high variability of PDC subsets. Although five of the studied patients harbored a RUNX1 mutation, no consistent feature of PDCs could be disclosed as associated with this variant. Moreover, the one normal single-node small subset of PDC detected in the merged file of six normal BM could be retrieved in the remission BM samples of three successfully treated patients. This study highlights the capacity of unsupervised flow cytometry analysis to delineate cell subsets not detectable with classical supervised tools. Full article

Acute myeloid leukaemia (AML) is a haematological cancer with poor outcomes due to a lack of efficacious targeted therapies. The Nuclear Factor of Activated T Cells (NFAT) family of transcription factors is well characterised as a regulator of the cell cycle and differentiation in the myeloid lineage. Recent evidence has demonstrated that NFAT family members may have roles in regulating AML leukemogenesis and resistance to targeted therapy in myeloid leukaemia. Furthermore, gene expression data from patient samples show that some NFATs are more highly expressed in poorly differentiated AML and after disease relapse, implying that the NFAT family may have roles in specific types of AML. This review outlines the evidence for the role of NFAT in healthy myeloid tissue and explores how NFAT might regulate AML pathogenesis, highlighting the potential to target specific NFAT proteins therapeutically in AML. Full article

Myelodysplastic syndromes are clonal disorders with morphological dysplasia, a variable degree of cytopenia and a risk of transformation to acute myeloid leukemia. Prognosis is very variable and is defined by blast count, cytopenia, cytogenetics and more recently by somatic mutations, with IPSS or revised IPSS score being the most widely used to assess disease risk. HSCT remains the only curative treatment to date, with high-risk patients obtaining the biggest benefit. However, NRM should be carefully assessed before indicating the transplant in this usually old population, where organ toxicity and comorbid conditions are to be considered. Multi-domain assessment tools, such as CGA (comprehensive geriatric assessment) and EBMT score, are useful in this context and might guide physician decisions regarding the transplant. Indeed, with the development of reduced intensity conditioning regimens, the number of patient candidates for an HSCT has increased. Regarding pre-transplant treatment, patients with a blast excess > 10% might be treated with HMAs or chemotherapy, although there are no randomized trials confirming the benefit of this approach, even when achieving a complete response. Concerning donor choice, matched sibling donors continue to be the first option, although matched unrelated donors, and more recently haploidentical donors, have proven to be valid options and should be offered in the absence of a related donor. Relapse remains the main cause of transplantation failure. MRD assessment and pre-emptive or prophylactic use of HMA or other targeted inhibitors with or without DLI are accepted strategies to reduce relapse risk, but the prognosis in this context remains dismal, and is the subject for several ongoing clinical protocols. Full article

Acute myeloid leukemia (AML) is a heterogeneous aggressive hematologic malignancy derived from malignant clones that promote their own growth and survival at the expense of normal hematopoiesis resulting in life-threatening bleeding and infections. Traditional initial AML therapy has been centered on a backbone of intensive chemotherapy often composed of an anthracycline and cytarabine. This strategy has proven most effective in patients less than 60 years of age due to both patient-related tolerability factors as well as changes in AML biology centered on chemotherapy refractory mutational profiles that are seen with advancing age. Recent improvements in frontline AML therapy have been seen in patients 60 years of age and over, a population most typically referred to as “older” adult AML. Herein, we describe the characteristics of “older” adult AML, review the differences in outcomes amongst those 60–75 and those over 75 years of age, and cite challenges in delivering frontline therapies within this group based not only on therapeutic toxicity but also on the patient’s overall level of “fitness” and inherent biology. We also discuss the role of targeted therapies that inhibit specific mutations and have the potential to deliver improved efficacy with less side effects while also recognizing that some selected older AML patients still benefit from intensive induction therapy. Full article

The formation and deposition of fibrils derived from immunglobulin light chains is a hallmark of systemic AL amyloidosis. A particularly remarkable feature of the disease is the diversity and complexity in pathophysiology and clinical manifestations. This is related to the variability of immunoglobulins, as virtually every patient has a variety of mutations resulting in their own unique AL protein and thus a unique fibril deposited in the body. Here, I review recent biochemical and biophysical studies that have expanded our knowledge on how versatile the structure of AL fibrils in patients is and highlight their implications for the molecular mechanism of fibril formation in AL amyloidosis. Full article

Background: Multiple methods have been implemented to limit the impact of radiotherapy on patients affected by mediastinal lymphoma, including breathing control techniques, image-guided radiotherapy (IGRT) and intensity-modulated radiotherapy (IMRT), although the actual diffusion of such techniques is unclear. No surveys have been published to date evaluating the techniques adopted at different centers. Methods: A survey with a dedicated questionnaire was submitted to 195 Italian radiotherapy centers, assessing items regarding the characteristics of the center and clinical practice in the treatment of mediastinal lymphomas. Results: A total of 43 centers (22%) responded, the majority of which were university hospitals (37.2%) or cancer care centers (27.9%). In 95.4% of the centers, IMRT was used in the clinical practice, and the most frequently employed techniques were VMAT (48.8% of centers) and non-rotational IMRT (31.7%). Comparison of multiple plans was performed by 66.7% of the responding centers. Dose constraints for organs at risk were consistently prescribed. IGRT techniques were adopted by 93% of the centers, while breathing control or gating techniques were routinely used by only 25.6% of the centers. A necessity to standardize OAR constraints and define guidelines was perceived by almost all participants. Conclusions: Modern radiotherapy techniques are widely used in the Italian centers, although with heterogeneous characteristics. Full article

Ineffective hematopoiesis is the major characteristic of early myelodysplastic syndromes. Its pathophysiology relies on a diversity of mechanisms supported by genetic events that develop in aging hematopoietic stem cells. Deletion and mutations trigger epigenetic modifications, and co-transcriptional and post-transcriptional deregulations of gene expression. Epistatic interactions between mutants may aggravate the phenotype. Amplification of minor subclones containing mutations that promote their growth and suppress the others drives the clonal evolution. Aging also participates in reprogramming the immune microenvironment towards an inflammatory state, which precedes the expansion of immunosuppressive cells such as Tregs and myeloid-derived suppressive cells that alters the anti-tumor response of effector cells. Integrating biomarkers of transcription/translation deregulation and immune contexture will help the design of personalized treatments. Full article

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with a variety of clinical manifestations related to viral tissue damage, as well as a virally induced immune response. Hyperstimulation of the immune system can serve as a trigger for autoimmunity. Several immune-mediated manifestations have been described in the course of SARS-CoV-2 infection. Immune thrombocytopenic purpura (ITP) and autoimmune hemolytic anemia (AIHA) are the most common hematologic autoimmune disorders seen in the course of SARS-CoV-2 infection. Vaccine-induced thrombocytopenia is a unique autoimmune hematologic cytopenia associated with SARS-CoV-2 vaccination. This paper will review the current literature on the association of SARS-CoV-2 infection and vaccination with autoimmune cytopenias and the clinical course of autoimmune cytopenias in patients with COVID-19. Full article

In this paper, we explore the application of Chimeric Antigen Receptor (CAR) T cell therapy for the treatment of Acute Lymphocytic Leukaemia (ALL) by means of in silico experimentation, mathematical modelling through first-order Ordinary Differential Equations and nonlinear systems theory. By combining the latter with systems biology on cancer evolution we were able to establish a sufficient condition on the therapy dose to ensure complete response. The latter is illustrated across multiple numerical simulations when comparing three mathematically formulated administration protocols with one of a phase 1 dose-escalation trial on CAR-T cells for the treatment of ALL on children and young adults. Therefore, both our analytical and in silico results are consistent with real-life scenarios. Finally, our research indicates that tumour cells growth rate and the killing efficacy of the therapy are key factors in the designing of personalised strategies for cancer treatment. Full article

We reviewed our studies on epidemiology and germline genetics of amyloidosis. In epidemiology, we considered both hereditary and non-hereditary amyloidosis. As the source of data, we used the nationwide Swedish hospital discharge register. We estimated the incidence of hereditary ATTR amyloidosis, for which Sweden is a global endemic area, at 2/million. Surprisingly, the disease was also endemic within Sweden; the incidence in the province with the highest incidence was 100 times higher than in the rest of Sweden. Risk of non-Hodgkin lymphoma increased five-fold in the affected individuals. Among non-hereditary amyloidosis, the incidence for AL amyloidosis (abbreviated as AL) was estimated at 3.2/million, with a median survival time of 3 years. Secondary systemic amyloidosis (most likely AA amyloidosis) showed an incidence of 1.15/million for combined sexes. The female rate was two times higher than the male rate, probably relating to the higher female prevalence of rheumatoid arthritis. The median survival time was 4 years. We also identified patients who likely had familial autoinflammatory disease, characterized by early onset and immigrant background from the Eastern Mediterranean area. Young Syrian descendants had the highest incidence rate, which was over 500 times higher than that in individuals with Swedish parents. Germline genetics focused on AL on which we carried out a genome-wide association study (GWAS) in three AL cohorts (N = 1129) from Germany, UK, and Italy. Single nucleotide polymorphisms (SNPs) at 10 loci showed evidence of an association at p < 10⁻⁵; some of these were previously documented to influence multiple myeloma (MM) risk, including the SNP at the IRF4 binding site. In AL, SNP rs9344 at the splice site of cyclin D1, influencing translocation (11;14), reached the highest significance, p = 7.80 × 10⁻¹¹; the SNP was only marginally significant in MM. The locus close to gene SMARCD3, involved in chromatin remodeling, was also significant. These data provide evidence for common genetic susceptibility to AL and MM. We continued by analyzing genetic associations in nine clinical profiles, characterized by organ involvement or Ig profiles. The light chain only (LCO) profile associated with the SNP at the splice site of cyclin D1 with p = 1.99 × 10⁻¹². Even for the other profiles, distinct genetic associations were found. It was concluded that the strong association of rs9344 with LCO and t(11;14) amyloidosis offer attractive mechanistic clues to AL causation. Mendelian randomization analysis identified associations of AL with increased blood monocyte counts and the tumor necrosis factor receptor superfamily member 17 (TNFRSF17 alias BCMA) protein. Two other associations with the TNFRSF members were found. We discuss the corollaries of the findings with the recent success of treating t(11;14) AL with a novel drug venetoclax, and the application of BCMA as the common target of plasma cell immunotherapies. Full article

Chronic myelomonocytic leukemia (CMML) was named 50 years ago to describe a myeloid malignancy whose onset is typically insidious. This disease is now classified by the World Health Organisation as a myelodysplastic syndrome (MDS)-myeloproliferative neoplasm (MPN) overlap disease. Observed mostly in ageing people, CMML is characterized by the expansion of monocytes and, in many cases, granulocytes. Abnormal repartition of circulating monocyte subsets, as identified by flow cytometry, facilitates disease recognition. CMML is driven by the accumulation, in the stem cell compartment, of somatic variants in epigenetic, splicing and signaling genes, leading to epigenetic reprogramming. Mature cells of the leukemic clone contribute to creating an inflammatory climate through the release of cytokines and chemokines. The suspected role of the bone marrow niche in driving CMML emergence and progression remains to be deciphered. The clinical expression of the disease is highly diverse. Time-dependent accumulation of symptoms eventually leads to patient death as a consequence of physical exhaustion, multiple cytopenias and acute leukemia transformation. Fifty years after its identification, CMML remains one of the most severe chronic myeloid malignancies, without disease-modifying therapy. The proliferative component of the disease that distinguishes CMML from severe MDS has been mostly neglected. This review summarizes the progresses made in disease understanding since its recognition and argues for more CMML-dedicated clinical trials. Full article

Patients with myeloproliferative neoplasm (MPN) are potentially facing diminished life expectancy and decreased quality of life, due to thromboembolic and hemorrhagic complications, progression to myelofibrosis or acute leukemia with ensuing signs of hematopoietic insufficiency, and disturbing symptoms such as pruritus, night sweats, and bone pain. In patients with essential thrombocythemia (ET) or polycythemia vera (PV), current guidelines recommend both primary and secondary measures to prevent thrombosis. These include acetylsalicylic acid (ASA) for patients with intermediate- or high-risk ET and all patients with PV, unless they have contraindications for ASA use, and phlebotomy for all PV patients. A target hematocrit level below 45% is demonstrated to be associated with decreased cardiovascular events in PV. In addition, cytoreductive therapy is shown to reduce the rate of thrombotic complications in high-risk ET and high-risk PV patients. In patients with prefibrotic primary myelofibrosis (pre-PMF), similar measures are recommended as in those with ET. Patients with overt PMF may be at increased risk of bleeding and thus require a more individualized approach to thrombosis prevention. This review summarizes the thrombotic risk factors and primary and secondary preventive measures against thrombosis in MPN. Full article