Bone Marrow Blood Research Articles

Cytogenetic, Clinical, Hematologic, Demographic, Immunohistochemical, and Flow Cytometry Characteristics of Patients with Plasma Cell Neoplasm in Five Years: A First Report from Iran.

The aggregation of clonal plasma cells causes plasma cell neoplasms, which vary in severity and clinical outcomes. The present research focused on the epidemiological, clinical, immunologic, and cytogenetic characteristics of plasma cell neoplasms. In this five-year retrospective cross-sectional study, demographic information such as age and sex, calcium elevation, renal insufficiency, anemia, and bone lesion (CRAB) characteristics, as well as laboratory data including bone marrow and peripheral blood film results, immunohistochemistry, flow cytometry, and cytogenetic study outcomes were collected at Shiraz University of Medical Sciences, Shiraz, Iran. The collected data were analyzed using SPSS Statistics software (version 20.0). Descriptive statistics were reported as numbers, percentages, and mean±SD. 417 newly diagnosed plasma cell neoplasm patients were confirmed by bone marrow or other tissue biopsy tests. 279 patients were men (66.9%). The most prevalent age group was 60-64 years old (18.46%). Plasma cell myeloma (PCM) affected 355 (85.13%) patients, while monoclonal gammopathy of undetermined significance (MGUS) affected 6 (1.43%) patients. Solitary plasmacytoma was seen in 56 (13.42%) patients. At the time of diagnosis, 119 (33.52%) of 355 PCM patients were asymptomatic, whereas 236 (66.47%) patients had at least one CRAB symptom, 55 (15.49%) had two or more, and 14 (3.94%) had three or more. There were 7 (1.97%) cases of amyloidosis. Cytogenetic abnormalities were found in 51.28% (40/78) of the patients. Twenty-one individuals (52.5%) were hyperdiploid with multiple trisomy, while 19 (47.50%) were not. When diagnosed, Iranian PCM patients might have more advanced disease. PCM was more prevalent in young adults, and hyperdiploid was the most common cytogenetic finding in this investigation.

The exo-microRNA (miRNA) signaling pathways in pathogenesis and treatment of stroke diseases: Emphasize on mesenchymal stem cells (MSCs).

A major factor in long-term impairment is stroke. Patients with persistent stroke and severe functional disabilities have few therapy choices. Longnoncoding RNAs (lncRNAs) may contribute to the regulation of the pathophysiologic processes of ischemic stroke as shown by altered expression of lncRNAsand microRNA (miRNAs) in blood samples of acute ischemic stroke patients. On the other hand, multipotent mesenchymal stem cells (MSCs) increase neurogenesis, and angiogenesis, dampen neuroinflammation, and boost brain plasticity to improve functional recovery in experimental stroke models. MSCs can be procured from various sources such as the bone marrow, adipose tissue, and peripheral blood. Under the proper circumstances, MSCs can differentiate into a variety of mature cells, including neurons, astrocytes, and oligodendrocytes. Accordingly, the capability of MSCs to exert neuroprotection and also neurogenesis has recently attracted more attention. Nowadays, lncRNAs and miRNAs derived from MSCs have opened new avenues to alleviate stroke symptoms. Accordingly, in this review article, we examined various studies concerning the lncRNAs and miRNAs'role in stroke pathogenesis and delivered an overview of the therapeutic role of MSC-derived miRNAs and lncRNAs in stroke conditions.

Significance of IgH Gene Rearrangement in Surveillance of Minimal Residual Disease after Autologous Hematopoietic Stem Cell Transplantation in Multiple Myeloma

To investigate the value of immunoglobulin heavy chain (IgH) gene rearrangement in monitoring minimal residual disease (MRD) in multiple myeloma (MM) received autologous hematopoietic stem cell transplantation(auto-HSCT). The clinical data of 26 MM patients who received auto-HSCT in the Department of Hematology, Wuhan First Hospital from 2018 to 2022 were collected. IgH rearrangement was detected by multiplex PCR combined with capillary electrophoresis fragment analysis to evaluate minimal residual disease (MRD), and the outcome of the disease was analyzed statistically. Among the 26 MM patients, 18 were males and 8 were females, with a median age of 59(41-70) years. The median follow-up time after transplantation was 33 (7-52) months. Compared with the IgH rearrangement negative group (n=17), the proportion of CR and sCR of patients with IgH rearrangement positive in bone marrow samples before auto-HSCT at 3 months after transplantation was lower （1/9 vs 14/17）, and the duration of remission (DOR) after transplantation was shorter（10.78±4.35 vs 15.88±5.22 months）, with statistically significant difference in DOR between the two groups(P < 0.05). Compared with IgH rearrangement negative group (n=21), the proportion of CR and sCR of patients with positive IgH rearrangement results from peripheral blood stem cell collection at 3 months after transplantation was lower（0/5 vs 15/21）, the duration of remission (DOR) after transplantation was shorter（9.60±4.83 vs 15.19±5.11 months）, and the difference in DOR between the two groups was statistically significant (P < 0.05). During the follow-up period, 5 patients (5/9) with positive IgH rearrangement results in bone marrow specimens died, and all patients with negative IgH rearrangement results survived. Four patients (4/5) with positive IgH rearrangement results by peripheral blood stem cell samples died, while one patient (1/21) with negative IgH rearrangement results died. In both bone marrow and peripheral blood stem cell samples, the survival time of IgH rearrangement-positive patients after transplantation was shorter than that of IgH rearrangement-negative patients(P < 0.05). Logistic regression analysis showed that gender, disease stage, the proportion of bone marrow smear plasma cells at initial diagnosis, stem cell mobilization plan, efficacy evaluation before transplantation (≥CR and <CR), and CD34+ cell count had no effect on IgH rearrangement results of stem cell collection (P >0.05). By detecting IgH rearrangement of MM patients receiving auto-HSCT, the depth of MRD can be further evaluated, which has a certain guiding significance for the efficacy and prognosis of the disease.

A flow cytometric approach to compare stem cell apoptosis in aplastic anemia and hypoplastic myelodysplastic syndrome.

Aplastic anemia (AA) is a disease caused by bone marrow (BM) failure. There are many similarities between AA and hypoplastic myelodysplastic syndrome (MDS); hence, differentiating them could be problematic. The current study aimed to use the new technique of flow cytometry as a possible diagnostic tool for AA and hypoplastic MDS. The BM mononuclear cell (BMMC) and blood samples from 44 participants (17 patients with AA, 13 with hypoplastic MDS, and 14 healthy controls) were collected. The flow cytometric analysis of the cluster of differentiation 34 (CD34) levels and cell apoptosis was performed for all sample types. Patients with hypoplastic MDS showed a high percentage of CD34+ cells with low apoptosis, while those with AA showed a low percentage of CD34+ cells with high apoptosis. Despite the similarity in the clinical presentation of hypoplastic MDS and AA, they are biologically different disorders. Increased CD34+ cell numbers with high viability may provide a useful and accurate tool for the differential diagnosis of hypoplastic MDS from AA.

Impact of different genetic mutations on granulocyte development and G-CSF responsiveness in congenital neutropenia

AbstractCongenital neutropenia (CN) is a genetic disorder characterized by persistent or intermittent low peripheral neutrophil counts, thus increasing susceptibility to bacterial and fungal infections. Various forms of CN, caused by distinct genetic mutations, exhibit differential responses to granulocyte colony–stimulating factor (G-CSF) therapy, with the underlying mechanisms not fully understood. This study presents an in-depth comparative analysis of clinical and immunological features in 5 CN patient groups (severe congenital neutropenia [SCN]1, SCN3, cyclic neutropenia [CyN], warts, hypogammaglobulinaemia, infections and myelokathexis [WHIM], and Shwachman-Bodian-Diamond Syndrome [SBDS]) associated with mutations in ELANE, HAX1, CXCR4, and SBDS genes. Our analysis led to the identification of 11 novel mutations in ELANE and 1 each in HAX1, CXCR4, and G6PC3 genes. Investigating bone marrow (BM) granulopoiesis and blood absolute neutrophil count after G-CSF treatment, we found that SCN1 and SCN3 presented with severe early-stage disruption between the promyelocyte and myelocyte, leading to a poor response to G-CSF. In contrast, CyN, affected at the late polymorphonuclear stage of neutrophil development, showed a strong G-CSF response. WHIM, displaying normal neutrophil development, responded robustly to G-CSF, whereas SBDS, with moderate disruption from the early myeloblast stage, exhibited a moderate response. Notably, SCN1 uniquely impeded neutrophil development, whereas SCN3, CyN, WHIM, and SBDS also affected eosinophils and basophils. In addition, SCN1, SCN3, and CyN presented with elevated serum immunoglobulins, increased BM plasma cells, and higher A Proliferation-Inducing Ligand levels. Our study reveals a strong correlation between the stage and severity of granulocyte development disruption and the efficacy of G-CSF therapy.

Virus-reactive T cells expanded in aplastic anemia eliminate hematopoietic progenitor cells by molecular mimicry

AbstractAcquired aplastic anemia is a bone marrow failure syndrome characterized by hypocellular bone marrow and peripheral blood pancytopenia. Frequent clinical responses to calcineurin inhibition and antithymocyte globulin strongly suggest critical roles for hematopoietic stem/progenitor cell–reactive T-cell clones in disease pathophysiology; however, their exact contribution and antigen specificities remain unclear. We determined differentiation states and targets of dominant T-cell clones along with their potential to eliminate hematopoietic progenitor cells in the bone marrow of 15 patients with acquired aplastic anemia. Single-cell sequencing and immunophenotyping revealed oligoclonal expansion and effector differentiation of CD8+ T-cell compartments. We reexpressed 28 dominant T-cell receptors (TCRs) of 9 patients in reporter cell lines to determine reactivity with (1) in vitro–expanded CD34+ bone marrow, (2) CD34− bone marrow, or (3) peptide pools covering immunodominant epitopes of highly prevalent viruses. Besides 5 cytomegalovirus-reactive TCRs, we identified 3 TCRs that recognized antigen presented on hematopoietic progenitor cells. T cells transduced with these TCRs eliminated hematopoietic progenitor cells of the respective patients in vitro. One progenitor cell–reactive TCR (11A5) also recognized an epitope of the Epstein-Barr virus–derived latent membrane protein 1 (LMP1) presented on HLA-A∗02:01. We identified 2 LMP1-related mimotopes within the human proteome as activating targets of TCR 11A5, providing proof of concept that molecular mimicry of viral and self-epitopes can drive T cell–mediated elimination of hematopoietic progenitor cells in aplastic anemia.

Effect of voxelotor on murine bone marrow and peripheral blood with hematopoietic progenitor cell mobilization for gene therapy of sickle cell disease

In preparation for hematopoietic stem cell mobilization and collection, current ex vivo gene therapy protocols for sickle cell disease require patients to undergo several months of chronic red cell transfusion. For health care equity, alternatives to red cell transfusion should be available. We examined whether treatment with GBT1118, the murine analog of voxelotor, could be a safe and feasible alternative to red cell transfusion. We found that 3 weeks of treatment with GBT1118 increased the percentage of bone marrow hematopoietic stem cells and upon plerixafor mobilization, the percentage of peripheral blood hematopoietic stem cells. Our data suggest that voxelotor should be further explored for its potential safety and utility as preparation for hematopoietic stem cell mobilization and collection.

Low back pain patients with Modic type 1 changes exhibit distinct bacterial and non-bacterial subtypes

ObjectivesModic type 1 changes (MC1) are vertebral endplate bone marrow (BM) lesions observed on magnetic resonance images in sub-populations of chronic low back pain (CLBP) patients. The etiopathogenesis remains unknown and treatments that modify the underlying pathomechanisms do not exist. We hypothesized that two biological MC1 subtypes exist: a bacterial and a non-bacterial. This would have important implications for developing treatments targeting the underlying pathomechanisms. MethodsIntervertebral disc (IVD) samples adjacent to MC1 (n ​= ​34) and control (n ​= ​11) vertebrae were collected from patients undergoing spinal fusion. Cutibacterium acnes (C.acnes) genome copy numbers (GCNs) were quantified in IVD tissues with 16S qPCR, transcriptomic signatures and cytokine profiles were determined in MC1 and control BM by RNA sequencing and immunoassay. Finally, we assessed if C.acnes GCNs are associated with blood plasma cytokines. ResultsIVD tissues from control levels had <870 ​C.acnes GCNs/gram IVD. MC1-adjacent IVDs had either “low” (<870) or “high” (>870) C.acnes GCNs. MC1 patients with “high” C.acnes GCNs had upregulated innate immune cell signatures (neutrophil, macrophage/monocyte) and pro-inflammatory cytokines related to neutrophil and macrophage/monocyte function in the BM, consistent with a host defense against bacterium. MC1 patients with “low” C.acnes GCNs had increased adaptive immune cell signatures (T-and B-cell) in the BM and elevated IL-13 blood plasma levels. ConclusionOur study provides the first evidence for the existence of bacterial (C.acnes “high”) and non-bacterial (C.acnes “low”) subtypes in MC1 patients with CLBP. This supports the need for different treatment strategies.

CD371-positive pediatric B-cell acute lymphoblastic leukemia: propensity to lineage switch and slow early response to treatment

AbstractIn the effort to improve immunophenotyping and minimal residual disease (MRD) assessment in acute lymphoblastic leukemia (ALL), the international Berlin-Frankfurt-Münster (iBFM) Flow Network introduced the myelomonocytic marker CD371 for a large prospective characterization with a long follow-up. In the present study, we aimed to investigate the clinical and biological features of CD371-positive (CD371pos) pediatric B-cell precursor ALL (BCP-ALL). From June 2014 to February 2017, 1812 pediatric patients with newly diagnosed BCP-ALLs enrolled in trial AIEOP-BFM ALL 2009 were evaluated as part of either a screening (n = 843, Italian centers) or validation cohort (n = 969, other iBFM centers). Laboratory assessment at diagnosis consisted of morphological, immunophenotypic, and genetic analysis. Response assessment relied on morphology, multiparametric flow cytometry (MFC), and polymerase chain reaction (PCR)-MRD. At diagnosis, 160 of 1812 (8.8%) BCP-ALLs were CD371pos. This correlated with older age, lower ETV6::RUNX1 frequency, immunophenotypic immaturity (all P < .001), and strong expression of CD34 and of CD45 (P < .05). During induction therapy, CD371pos BCP-ALLs showed a transient myelomonocytic switch (mm-SW: up to 65.4% of samples at day 15) and an inferior response to chemotherapy (slow early response, P < .001). However, the 5-year event-free survival was 88.3%. Among 420 patients from the validation cohort, 27 of 28 (96.4%) cases positive for DUX4-fusions were CD371pos. In conclusion, in the largest pediatric cohort, CD371 is the most sensitive marker of transient mm-SW, whose recognition is essential for proper MFC MRD assessment. CD371pos is associated to poor early treatment response, although a good outcome can be reached after MRD-based ALL-related therapies.

IGH::NSD2 Fusion Gene Transcript as Measurable Residual Disease Marker in Multiple Myeloma.

Multiple myeloma (MM) is the second most common hematological malignancy. Approximately 15% of MM patients are affected by the t(4;14) translocation resulting in the IGH::NSD2 fusion transcript. Breakage occurs in three major breakpoint regions within the NSD2 gene (MB4-1, MB4-2, and MB4-3), where MB4-1 leads to the production of full-length protein, while truncated proteins are expressed in the other two cases. Measurable residual disease (MRD) has been conclusively established as a crucial prognostic factor in MM. The IGH::NSD2 fusion transcript can serve as a sensitive MRD marker. Using bone marrow (BM) and peripheral blood (PB) samples from 111 patients, we developed a highly sensitive quantitative real-time PCR (qPCR) and digital PCR (dPCR) system capable of detecting fusion mRNAs with a sensitivity of up to 1:100,000. PB samples exhibited sensitivity three orders of magnitude lower compared to BM samples. Patients with an MB4-2 breakpoint demonstrated significantly reduced overall survival (p = 0.003). Our novel method offers a simple and sensitive means for detecting MRD in a substantial proportion of MM patients. Monitoring may be carried out even from PB samples. The literature lacks consensus regarding survival outcomes among patients with different NSD2 breakpoints. Our data align with previous findings indicating that patients with the MB4-2 breakpoint type tend to exhibit unfavorable overall survival.

A biphenotypic lymphocyte subset displays both T- and B-cell functionalities

T cell/B cell mixed phenotypic lymphocytes have been observed in different disease contexts, yet their presence and function in physiological conditions remain elusive. Here, we provide evidence for the existence of a lymphocyte subset endogenously expressing both T- and B-cell lineage markers in mice. The majority of these T/B phenotypic lymphocytes (CD3+CD19+) show an origin of pro/pre B cells and distribute widely in mouse bone marrow, lymph nodes, spleen, and peripheral blood. Functional assays show that these biphenotypic lymphocytes can be activated through stimulating TCR or BCR signaling pathways. Moreover, we show that these cells actively participate both the humoral and cellular immune responses elicited by vaccination. Compared to conventional T cells, these biphenotypic lymphocytes can secrete a higher level of IL-2 but a lower level of TNF-α upon antigen specific stimulation. An equivalent lymphocyte subset is found in freshly isolated human PBMCs and exhibits similar functionality, albeit at a lower frequency than in mice.

Association between clinical outcomes, peripheral blood and cytomorphologic features of bone marrow in visceral leishmaniasis

IntroductionAn intracellular parasite of mononuclear phagocytes, mainly distributed in the bone marrow and the spleen, causes visceral leishmaniasis. Complete blood count (CBC) reveals the poorly understood pathogenesis of anemia, leukopenia and thrombocytopenia. Our study aimed to compare the CBC with bone marrow cytomorphological features and their association with clinical outcomes to clarify this relevant issue. MethodsThe CBC and bone marrow of 118 patients were described by two hematologists and compared to check their association with each other and mortality. ResultsPeripheral cytopenias were common findings, particularly anemia, as seen in almost all patients. No relationship was found between values of hemoglobin, neutrophils and platelet count with fatal outcomes. The bone marrow was normocellular in 61.9% of the cases. Dysplasia figures were frequent and 49.1% of the samples had dysgranulopoiesis. Additionally, erythroid hyperplasia was found in 72% of the patients with severe anemia. Patients with reduced bone marrow cellularity, erythroid hypercellularity and dyserythropoiesis seem to have a riskier disease. ConclusionThe study results suggest that the bone marrow of patients with visceral leishmaniasis manifests a reactional pattern to the inflammatory event, thereby modulating cytokines and other colony growth factors. This compensatory response may be dysplastic and ineffective and generate peripheral cytopenias of varying intensity. Further studies are needed to clarify the signaling pathways involved, which may be used as therapeutic tools in the future.

Investigating the effect of immunomagnetic separation on the immunophenotype and viability of plasma cells in plasma cell disorders.

Plasma cell enrichment plays a pivotal role in the accurate prognosis and molecular characterization of multiple myeloma. The separation is commonly carried out by positive cell selection using CD138 monoclonal antibody conjugated to magnetic beads. Optimally, during the separation procedure, the cells should neither be damaged, nor should their phenotype be significantly altered, as these changes would falsify the results if the isolated cells were subsequently used. For this reason, we investigated the expression patterns of different surface markers by flow cytometry before and after magnetic isolation using bone marrow or peripheral blood samples from 12 patients with plasma cell disorders. The selected markers are not only used as backbone markers in routine diagnostics (CD19, CD38, CD45, CD117, and CD138), but they also play an important role in cell adhesion and connection with microenvironment (CD44, CD49d, CD56, and CD81) or possibly drug resistance (CD69, CD86, and CD184), making them promising targets for myeloma research. Moreover, we examined the effects of separation on cell viability in 8 cases. The intensities of 8 out of the 12 investigated markers were slightly influenced, while CD138, CD38, CD56, and CD184 were changed significantly, however the immunophenotype of the cells was not changed. Positive markers remained positive and negative ones remained negative after the separation procedure. In addition, the number of apoptotic plasma cells was significantly reduced during separation, facilitating further examination of the cells. Our results showed that magnetic isolation can be considered as a reliable option but the immunophenotype of plasma cells should be validated after the separation if the intensities of the markers are important for further experiments.

RNASeq Analysis for Accurate Identification of Fusion Partners in Tumor Specific Translocations Detected by Standard FISH Probes in Hematologic Malignancies.

Fluorescence labeled DNA probes and in situ hybridization methods had shorter turn round time for results revolutionized their clinical application. Signals obtained from these probes are highly specific, yet they can produce fusion signals not necessarily representing fusion of actual genes due to other genes included in the probe design. In this study we evaluated discordance between cytogenetic, FISH and RNAseq results in 3 different patients with hematologic malignancies and illustrated the need to perform next generation sequencing (NGS) or RNASeq to accurately interpret FISH results. Bone marrow or peripheral blood karyotypes and FISH were performed to detect recurring translocations associated with hematologic malignancies in clinical samples routinely referred to our clinical cytogenetics laboratory. When required, NGS was performed on DNA and RNA libraries to detect somatic alterations and gene fusions in some of these specimens. Discordance in results between these methods is further evaluated. For a patient with plasma cell leukemia standard FGFR3 / IGH dual fusion FISH assay detected fusion that was interpreted as FGFR3-positive leukemia, whereas NGS/RNASeq detected NSD2::IGH. For a pediatric acute lymphoblastic leukemia patient, a genetic diagnosis of PDGFRB-positive ALL was rendered because the PDGFRB break-apart probe detected clonal rearrangement, whereas NGS detected MEF2D::CSF1R. A MYC-positive B-prolymphocytic leukemia was rendered for another patient with a cytogenetically identified t(8;14) and MYC::IGH by FISH, whereas NGS detected a novel PVT1::RCOR1 not previously reported. These are 3 cases in a series of several other concordant results, nevertheless, elucidate limitations when interpreting FISH results in clinical applications, particularly when other genes are included in probe design. In addition, when the observed FISH signals are atypical, this study illustrates the necessity to perform complementary laboratory assays, such as NGS and/or RNASeq, to accurately identify fusion genes in tumorigenic translocations.

ABO incompatibility haploidentical peripheral blood stem cell transplantation combined with a single cord blood unit for severe aplastic anemia patients.

To observe the efficacy of haploidentcial peripheral blood stem cell transplantation combined with a single unrelated cord blood unit for severe aplastic anemia patients with donor-recipient ABO incompatibility. This was a retrospective cohort study and data of 57 severe aplastic anemia patients underwent haploidentical stem cell transplantation from August 1, 2018 to February 28, 2022 in the First Affiliated Hospital of Xi'an Jiaotong University was retrospectively analyzed. All patients were divided into two groups, the donor-recipient ABO matched group (bone marrow+peripheral blood group) using haploidentical bone marrow and peripheral blood stem cells as grafts, and donor-recipient ABO mismatched group (cord blood+peripheral blood group), using unrelated cord blood and haploidentical peripheral blood stem cells as grafts. The differences of hematopoietic reconstitution, acute and chronic graft-versus-host disease, Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infection, and overall survival between the two groups were compared. There were 30 cases in cord blood+peripheral blood group and 27 cases in bone marrow+peripheral blood group. One patient in bone marrow+peripheral blood group had primary graft failure, while other patients were successfully implanted. There were no significant differences of neutrophil and platelet recovery rates between two groups. The erythrocyte recovery time of cord blood+peripheral blood group was slower than that of bone marrow+peripheral blood group (p < 0.05). There was no significant difference of the incidence of graft-versus-host disease, CMV, EB virus infection and post-transplant lymphoproliferative disorders between two groups (p > 0.05). The incidence of grade III-IV acute graft-versus-host disease in cord blood+peripheral blood group was higher than that of bone marrow+peripheral blood group (p < 0.05). The incidence of intestinal graft-versus-host disease was higher in minor ABO-mismatched transplantation than that in major ABO-mismatched transplantation (p < 0.05). There was no significant difference of overall survival between two groups (p > 0.05). These findings suggest that haploidentical peripheral blood stem cell transplantation combined with a single cord blood unit may be an alternative option for severe aplastic anemia patients with donor-recipient ABO incompatibility.

Treatment outcome of the tyrosine kinase inhibitor (bosutinib) in previously treated chronic myeloid leukemia patients (sample of Iraqi patients)

Abstract: BACKGROUND: Chronic myeloid leukemia (CML) is a type of myeloproliferative neoplasm characterized by the excessive accumulation of malignant myeloid cells in the bone marrow and peripheral blood. This condition is primarily triggered by a specific chromosomal translocation known as t(9;22) (q34.13;q11.23), which leads to the formation of the BCR-ABL fusion gene. The treatment landscape for CML has undergone significant changes with the approval of tyrosine kinase inhibitors (TKIs) targeting the BCR-ABL1 kinase activity. One such inhibitor is bosutinib, which has been available for several years to treat patients with chronic, accelerated, and blast-phase CML who have shown resistance or intolerance to previous therapies. OBJECTIVES: The aim of this study was to assess efficacy and safety of Bosutinib as a 2nd line therapy in CML patients, in addition to effect of adherence to treatment on patients response. PATIENTS AND METHODS: Eighty-five patients with CML were enrolled in a prospective cohort study from October 2021 to October 2022 at Hematology Center in Medical City Complex – Baghdad. All patients failed to at least one TKI, and all of them started escalated dose of bosutinib. The patients were followed-up by assessing molecular and cytogenetic response at 3 and 6 months and monitored carefully for adverse events (AEs) which were graded by common terminology IX criteria for AEs version 5. Adherence to bosutinib was also monitored by a specific adherence scale to optimize the response rate to treatment. RESULTS: The mean age of patients was 47.3 ± 14.9 (range: 18–77), with male:female ratio 1.4:1. Status of CML patients showed that 89.4% were in the chronic phase, 5.8% in accelerated phase, and 4.7% in blast phase. Regarding the number of previous TKIs before bosutinib, 72.9% of patients failed to prior one TKI (imatinib). At 6 months (72.3%), patients achieve optimal response according to European Leukemia Net criteria 2013. Gastrointestinal symptoms and dermatological manifestations were the most common nonhematological AEs of bosutinib. According to 9-item Morisky Medication Adherence Scale, 42% of patients were adherent to medication which showed a significant association with a higher number of optimal response (P = 0.0001). CONCLUSION: Bosutinib is effective with a high and promising response as a subsequent line treatment in CML patients, and it is generally safe and associated with mild-to-moderate tolerable and manageable AEs. Adherence to the drug plays a significant role in optimal response to bosutinib.

Mechanisms underlying therapeutic resistance of tyrosine kinase inhibitors in chronic myeloid leukemia.

Chronic myeloid leukemia (CML) is a malignant clonal disease involving hematopoietic stem cells that is characterized by myeloid cell proliferation in bone marrow and peripheral blood, and the presence of the Philadelphia (Ph) chromosome with BCR-ABL fusion gene. Treatment of CML has dramatically improved since the advent of tyrosine kinase inhibitors (TKI). However, there are a small subset of CML patients who develop resistance to TKI. Mutations in the ABL kinase domain (KD) are currently recognized as the leading cause of TKI resistance in CML. In this review, we discuss the concept of resistance and summarize recent advances exploring the mechanisms underlying CML resistance. Overcoming TKI resistance appears to be the most successful approach to reduce the burden of leukemia and enhance cures for CML. Advances in new strategies to combat drug resistance may rapidly change the management of TKI-resistant CML and expand the prospects for available therapies.

A Comparative Study on the Effects of Mesenchymal Stem Cells and Their Conditioned Medium on Caco-2 Cells as an In Vitro Model for Inflammatory Bowel Disease.

Recent research indicates that mesenchymal stem cells (MSCs), known for their anti-inflammatory and anti-infectious properties, could be a promising alternative for treating inflammatory diseases such as inflammatory bowel disease (IBD). This study examined how MSCs and their derivatives, when cocultured with interleukin-1β (IL-1β)-stimulated Caco-2 cells, affect the expression of genes related to inflammation, microbes, and apoptosis. In the experiment, Caco-2 cells were exposed to 10 ng/mL of IL-1β for 24 h. MSCs were sourced from human bone marrow, adipose tissue (AD-MSC), and menstrual blood. These MSCs and their conditioned medium (CM) were then cocultured with the IL-1β-induced Caco-2 cells. After 48 h, gene expression levels were analyzed using real-time PCR, and the data were statistically evaluated using T-tests, U-Mann-Whitney, and Tukey's post hoc analyses. The results indicated that IL-1β at 10 ng/mL was the optimal concentration for inducing Caco-2 cells with the highest viability and minimal damage. Among the MSCs tested, AD-MSCs were the most effective in regulating gene expression. Specifically, AD-MSC treatment significantly reduced the mRNA expression of TNF-α and IL-1β, both of which are crucial in sustaining inflammatory responses (p ≤ 0.05). This study concludes that AD-MSCs have superior effects compared to other MSC sources in modulating genes associated with inflammation, antibacterial effects, and apoptosis in an in vitro model of IBD using Caco-2 cells.

The roles of phosphorylation of signaling proteins in the prognosis of acute myeloid leukemia.

Signaling pathways of Retinoblastoma (Rb) protein, Akt-kinase, and Erk-kinase (extracellular signal-regulated kinase) have an important role in the pathogenesis of acute myeloid leukemia. Constitutive activation of these proteins by phosphorylation contributes to cell survival by regulation of cell cycle, proliferation and proapoptotic signaling processes. According to previous data phosphorylated forms of these proteins represent a worse outcome for cancer patients. We investigated the presence of phosphorylated Rb (P-Rb), Akt (P-Akt) and Erk (P-Erk) proteins by Western blot technique using phospho-specific antibodies in bone marrow or peripheral blood samples of 69 AML patients, 36 patients with myelodysplastic syndrome (MDS) and 10 healthy volunteers. Expression level of PTEN (Phosphatase and tensin homolog) and PHLPP (PH domain and leucine-rich repeat Protein Phosphatase) phosphatases, the negative regulators of Akt kinase pathway were also examined. We tested the effect of these proteins on survival and on the correlation with known prognostic features in AML. We found 46.3% of AML patients had detectable P-Rb, 34.7% had P-Akt and 28.9% had P-Erk protein. 66.1% of patients expressing PTEN, 38.9% PHLPP, 37.2% both PTEN and PHLPP and 32.2% neither PTEN nor PHLPP phosphatases. Compared to nucleophosmin mutation (NPMc) negative samples P-Erk was significantly less in nucleophosmin mutated patients, P-Rb was significantly less in patients' group with more than 30G/L peripheral leukocyte count by diagnosis. PHLPP was significantly present in FAB type M5. The expression of P-Rb represented significant better overall survival (OS), while P-Akt represented significantly worse event-free survival (EFS) in unfavorable cytogenetics patients. The presence of both PHLPP and PTEN phosphatases contributes to better OS and EFS, although the differences were not statistically significant. We confirmed significant positive correlation between P-Akt and PHLPP. Assessing the phosphorylation of Rb, Akt and Erk may define a subgroup of AML patients who would benefit especially from new targeted treatment options complemented the standard chemotherapy, and it may contribute to monitoring remission, relapse or progression of AML.

Molecular Pathogenesis and Treatment Strategies of Chronic Myeloid Leukemia (CML)

Chronic Myeloid Leukemia (CML) is a myeloproliferative disease diagnosed in bone marrow, arising from a chromosomal translocation between chromosomes 9 and 22, resulting in the formation of fusion oncogene BCR–ABL. The product of this fusion oncogene is a new oncoprotein bcr–abl which possesses abnormal tyrosine kinase activity. In response to this, abnormal signaling pathway activation occurs, leading to cell transformation. BCR–ABL oncogene could be targeted by tyrosine kinase inhibitors (TKIs) to delay or inhibit the disease progression. Imatinib is the first drug designed against CML but resistance to this has led to the development of the second- and third generations of inhibitors that are active against many types of BCR–ABL gene mutations. However, somehow, due to disease progression, TKIs do not remain as effective. There are three well-characterized phases of CML: The chronic phase (CP), the accelerated phase, and the terminal stage which is the blast crisis (BC) stage. In the CP of CML, mature granulocytes and myeloid precursors become aggregated majorly in the bone marrow and peripheral blood. The accelerated phase is marked by increased disease severity and an increase in progenitor/precursor cell number. In the BC stage, undifferentiated blast cells grow in number. Many patients with CML are diagnosed during the CP of the disease, so the survival rate of CML is high. However, 20% of CML patients proceed to advanced stages that result in drug resistance, intolerance, and mortality. So, for proper CML treatment, drugs are needed to target multiple BCR– ABL mutations, delay or stop disease progression, and overcome resistance caused by BCR–ABL independent mechanisms, especially during advanced phases of CML. Moreover, drugs could be developed to eradicate the stem cells of CML. These targets could be achieved by understanding mechanisms of disease progression, disease relapse, and drug resistance by utilizing high throughput molecular genetics, cell biology and immunology techniques.