Bone marrow recovery of hematopoietic stem cells and microenvironment after chemotherapy in childhood acute lymphoblastic leukemia: consecutive observations according to chemotherapy schedule

Dynamic evolution of bone marrow adipocyte in B cell acute lymphoblastic leukemia: insights from diagnosis to post-chemotherapy

Adipocyte is a unique and versatile component of bone marrow microenvironment (BMM). However, the dynamic evolution of Bone Marrow (BM) adipocytes from the diagnosis of B cell Acute Lymphoblastic Leukemia (B-ALL) to the post-treatment state, and how they affect the progression of leukemia, remains inadequately explicated. Primary patient-derived xenograft models (PDXs) and stromal cell co-culture system are employed in this study. We show that the dynamic evolution of BM adipocytes from initial diagnosis of B-ALL to the post-chemotherapy phase, transitioning from cellular depletion in the initial leukemia niche to a fully restored state upon remission. Increased BM adipocytes retards engraftment of B-ALL cells in PDX models and inhibits cells growth of B-ALL in vitro. Mechanistically, the proliferation arrest of B-ALL cells in the context of adipocytes-enrichment niche, might attribute to the presence of adiponectin secreted by adipocytes themselves and the absence of cytokines secreted by mesenchymal stem cell (MSCs). In summary, our findings offer a novel perspective for further in-depth understanding of the dynamic balance between BMM and B-ALL.

Application of High-Quality Nursing Intervention Based on Humanistic Care Combined with the Project Teaching Method in Patients with Acute Leukemia Undergoing Chemotherapy

Chemotherapy, the main treatment method of AL, can produce varying degrees of toxic and side effects on patients while killing tumor cells, resulting in decreased immune function of patients. We aim to explore the application effect of high-quality nursing intervention based on humanistic care combined with the project teaching method on patients with acute leukemia (AL) undergoing chemotherapy and its effect on their psychological state and satisfaction. 114 AL patients undergoing chemotherapy in the Department of Hematology of our hospital from July 2018 to July 2020 were chosen as the research objects and equally randomized into the experimental group (EG) and control group (CG). CG received routine nursing during chemotherapy, while EG received high-quality nursing intervention based on humanistic care combined with the project teaching method. Hospital Anxiety and Depression Scale (HAD) was adopted to evaluate the psychological state of patients in both groups after intervention, and the self-made nursing satisfaction questionnaire in our hospital was applied to evaluate the clinical nursing satisfaction. The HAD-A and HAD-D scores in the CG (P < 0.001) were significantly higher than the HAD-A and HAD-D scores in the EG after intervention. The scores of various coping styles in the EG after intervention were better than those in the CG (P < 0.05). Compared with the CG, the total nursing satisfaction after intervention was remarkably higher in the EG (P < 0.001), while the total incidence of adverse reactions during intervention was notably lower (P < 0.05). High-quality nursing intervention based on humanistic care combined with the project teaching method for AL patients undergoing chemotherapy can effectively relieve negative emotions, improve clinical nursing satisfaction, and reduce adverse reactions during chemotherapy.

The extracellular matrix: A key player in the pathogenesis of hematologic malignancies

Hematopoietic stem and progenitor cells located in the bone marrow lay the foundation for multiple lineages of mature hematologic cells. Bone marrow niches are architecturally complex with specific cellular, physiochemical, and biomechanical factors. Increasing evidence suggests that the bone marrow microenvironment contributes to the pathogenesis of hematological neoplasms. Numerous studies have deciphered the role of genetic mutations and chromosomal translocations in the development hematologic malignancies. Significant progress has also been made in understanding how the cellular components and cytokine interactions within the bone marrow microenvironment promote the evolution of hematologic cancers. Although the extracellular matrix is known to be a key player in the pathogenesis of various diseases, it's role in the progression of hematologic malignancies is less understood. In this review, we discuss the interactions between the extracellular matrix and malignant cells, and provide an overview of the role of extracellular matrix remodeling in sustaining hematologic malignancies.

Amelioration of cyclophosphamide-induced myelosuppression during treatment to rats with breast cancer through low-intensity pulsed ultrasound

To investigate the alleviating effects of low-intensity pulsed ultrasound (LIPUS) on myelosuppression of Sprague–Dawley rats with breast cancer induced by cyclophosphamide (CTX). Breast cancer in rats was triggered by intragastric gavage with 7,12-dimethylbenz[a]anthracene (150 mg/kg). Then, the rats with breast cancer were randomly allocated to the LIPUS group (n=50) and the control group (n=50). The LIPUS group was injected intraperitoneally with CTX (50 mg/kg) for 4 consecutive days and underwent LIPUS treatment at femoral metaphysis 20 min per day from the first day of injection for 7 consecutive days. The control group was injected with CTX (50 mg/kg) and treated with LIPUS without energy output. Blood, enzyme-linked immunosorbent assay (ELISA), real-time quantitative polymerase chain reaction, Hematoxylin and Eosin (H&E) staining, and scanning electron microscopy were applied to detect the changes. The results indicated that LIPUS significantly promoted the proliferation of bone marrow nucleated cells, white blood cells (WBCs), IgA, IgG, and IgM in the peripheral blood (P<0.05) without the damage to liver and kidney function simultaneously. The mechanisms may result from the LIPUS alleviation effect on bone marrow hematopoietic function through regulating cytokines such as LIPUS can increase the expression of granulocyte colony-stimulating factor (G-CSF), stem cell factor, transforming growth factor-β, and intercellular cell adhesion molecule-1, meanwhile LIPUS will decrease the expression of interleukin-6, tumor necrosis factor-α, and vascular cell adhesion molecule-1. LIPUS has potential to be a new adjuvant therapy method in clinic for ameliorating chemotherapy-induced myelosuppression.

Increased expression of immune checkpoint programmed cell death protein-1 (PD-1) on T cell subsets of bone marrow aspirates in patients with B-Lymphoblastic leukemia, especially in relapse and at diagnosis

BACKGROUND

We analyzed expression profiles of immune checkpoint receptors on T cell subsets and ligands on leukemic blasts in patients with B-lymphoblastic leukemia (B-ALL).

METHODS

Total 149 bone marrow (BM) samples obtained from 65 B-ALL patients with four different clinical status (41 at diagnosis, 54 in complete remission [CR], 34 in persistence, and 20 in relapse), and 32 BM control samples were prospectively enrolled. Expression of immune checkpoint receptor (programmed cell death protein-1 [PD-1]) on T cell subsets and ligands (PD-L1, PD-L2) on leukemic blasts was evaluated by flow cytometry, and was compared between patient subgroups.

RESULTS

Relapsed patients demonstrated highest PD-1 expression proportion and intensity on CD3⁺ CD4⁺ T cells with statistical significance when compared to patients in persistence/CR/BM controls (p = .027/<.001/<.001 and .012/.001/<.001, respectively). Newly diagnosed patients showed significantly lower PD-1 expression proportion on CD3⁺ CD4⁺ T cells than relapsed patients (p < .001), but their intensity was not significantly different. Relapsed patients showed significantly higher PD-1 expression proportion and intensity on CD3⁺ CD8⁺ T cells than patients in CR/BM controls (p = .022/.045 and .049/.005, respectively), but PD-1 expression status on them were not significantly different between relapsed and newly diagnosed patients. PD-L1/L2 expression on leukemic blasts was not significantly different between patient subgroups.

CONCLUSIONS

In BM aspirates from B-ALL patients, PD-1 expression on T-cell subsets is increased at diagnosis, and to a greater extent, at relapse. These data suggest the potential usefulness of PD-1 blockade in the treatment of B-ALL, particularly at relapse.

GEM on proliferation and apoptosis of childhood AL cells through inhibiting c-myc expression by upregulating miR-125a-3p

Effect of gemcitabine (GEM) on proliferation and apoptosis of childhood acute leukemia (AL) cells and the mechanism of action were investigated. Bone marrow and peripheral blood of 18 newly diagnosed children with childhood AL admitted to Yidu Central Hospital of Weifang were selected, and the miR-125a-3p level in peripheral blood of healthy children and children with AL was detected by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Leukemia cells from the bone marrow of children with AL were primarily cultured and purified to observe the morphology. miR-125a-3p mimic was transfected into childhood AL cells. The cells were randomly divided into three groups: control group, GEM group and GEM + miR-125a-3p mimic group. 5-ethynyl-2′-deoxyuridine (EdU) staining assay was chosen to detect the proliferation of childhood AL cells in each group. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining assay was adopted to determine apoptosis of childhood AL cells. The protein level of c-myc was measured via western blotting. Compared with that in the healthy children, the level of miR-125a-3p in the peripheral blood of children with AL was remarkably decreased. Compared with those in the control group, GEM inhibited proliferation and promoted apoptosis of childhood AL cells, and impeded the protein expression of c-myc in these cells. Compared with those in the GEM group, GEM + miR-125a-3p mimic notably reduced the proliferation and enhanced apoptosis of cells, and the protein expression of c-myc in cells was overtly reduced. The level of miR-125a-3p in peripheral blood of children with AL is obviously decreased. It is suggested in this study that GEM can inhibit the proliferation and promote apoptosis of childhood AL cells, and the mechanism may be related to upregulated miR-125a-3p inhibiting the expression of c-myc.