Dong-Feng Zeng

Role of Antithymocyte Globulin and Granulocyte-Colony Stimulating Factor-Mobilized Bone Marrow in Allogeneic Transplantation for Patients with Hematologic Malignancies

The main obstacle for allogeneic transplantation is delayed hematologic reconstitution and serious graft-versus-host disease (GVHD). The results of 128 patients with hematologic malignancies undergoing HLA-identical (n=52) or HLA-haploidentical/mismatched (n=76) hematopoietic stem cell transplantation (HSCT) performed during the same time period were compared. Patients with HLA-identical HSCT received unmanipulated granulocyte-colony stimulating factor-mobilized peripheral blood stem cells (G-PBSCs). Forty-six patients with HLA-haploidentical related HSCT received antithymocyte globulin (ATG) in conditioning regimens followed by the transplantation of the combination of unmanipulated G-PBSCs and granulocyte-colony stimulating factor-mobilized bone marrow (G-BM) and 30 patients with HLA-mismatched unrelated HSCT received ATG in conditioning regimens followed by the transplantation of unmanipulated G-PBSCs. All patients got successful hematopoietic engraftment. The cumulative incidences of grades I to II acute GVHD (aGVHD) on day 100 in the identical, haploidentical related and mismatched unrelated cohorts were 21.2%, 43.5%, and 53.3%, respectively. The cumulative incidences of chronic GVHD (cGVHD) in the identical, mismatched unrelated, and haploidentical related cohorts were 34.6%, 33.3%, and 10.9%, respectively. The 2-year relapse and treatment-related mortality (TRM) rates were 19.2%, 23.9%, 23.3%, and 9.6%, 8.7%, 10% for patients who underwent identical, HLA-haploidentical related, and mismatched unrelated transplantation, respectively. The 2-year probabilities of leukemia-free survival and overall survival were 72.2%, 70.6%, 68.1%, and 76.5%, 77.8%, 70.0% after identical, haploidentical related and mismatched unrelated transplantations, respectively. Multivariate analyses showed that only advanced disease stage and a diagnosis of disease had increased risk of relapse, treatment failure, and overall mortality. In conclusion, it is a feasible approach with acceptable outcomes for patients undergoing HLA-haploidentical related HSCT by the combination of G-PBSCs and G-BM with conditioning regimens including ATG.

Stem cell collection in unmanipulated HLA-haploidentical/mismatched related transplantation with combined granulocyte-colony stimulating factor-mobilised blood and bone marrow for patients with haematologic malignancies: the impact of donor characteristics and procedural settings.

Unmanipulated haploidentical/mismatched related transplantation with combined granulocyte‐colony stimulating factor‐mobilised peripheral blood stem cells (G‐PBSCs) and granulocyte‐colony stimulating factor‐mobilised bone marrow (G‐BM) has been developed as an alternative transplantation strategy for patients with haematologic malignancies. However, little information is available about the factors predicting the outcome of peripheral blood stem cell (PBSC) collection and bone marrow (BM) harvest in this transplantation. The effects of donor characteristics and procedure factors on CD34+ cell yield were investigated. A total of 104 related healthy donors received granulocyte‐colony stimulating factor (G‐CSF) followed by PBSC collection and BM harvest. Male donors had significantly higher yields compared with female donors. In multiple regression analysis for peripheral blood collection, age and flow rate were negatively correlated with cell yield, whereas body mass index, pre‐aphaeresis white blood cell (WBC) and circulating immature cell (CIC) counts were positively correlated with cell yields. For BM harvest, age was negatively correlated with cell yields, whereas pre‐BM collection CIC counts were positively correlated with cell yield. All donors achieved the final product of ≥6 ×106 kg−1 recipient body weight. This transplantation strategy has been shown to be a feasible approach with acceptable outcomes in stem cell collection for patients who received HLA‐haploidentical/mismatched transplantation with combined G‐PBSCs and G‐BM. In donors with multiple high‐risk characteristics for poor aphaeresis CD34+ cell yield, BM was an alternative source.

Human bone marrow mesenchymal stem cells expressing SDF-1 promote hematopoietic stem cell function of human mobilised peripheral blood CD34+ cells in vivo and in vitro

Purpose: There is mounting evidence demonstrating that stromal cell derived factor-1 (SDF-1) plays an important role in homing of hematopoietic progenitor cells to bone marrow. This study was aimed to assess whether bone marrow mesenchymal stem cells overexpressing exogenous SDF-1 could synergistically promote the homing of CD34+ (Cluster of Differentiation [CD]) cells to bone marrow of lethally irradiated severe combined immunodeficiency (SCID) mice. Methods: Human SDF-1 complementary Deoxyribonucleic acid (cDNA) was transfected into bone marrow-derived mesenchymal stem cells with recombinant lentiviral vector. The expression of SDF-1 was detected by real-time Polymerase Chain Reaction (PCR) and Enzyme-Linked Immunosorbent Assay (ELISA), and the ex vivo chemotaxis function on CD34+ cells was measured by coculture system and Transwell system. SDF-1 gene-modified mesenchymal stem cell (MSC) and CD34+ cells were infused into lethally irradiated SCID mice and the hematopoietic reconstitution in the recipient mice was examined. Results: Messenger ribonucleic acid (mRNA) and protein of SDF-1 in infected MSC were significantly higher than that of the non-infected control MSC (p < 0.05). The infected MSC have significant chemotaxis effect on CD34+ cells in vitro and promote hematopoietic reconstitution after CD34+ cell transplantation in vivo. Conclusion: MSC with high-level expression of SDF-1 can synergistically promote hematopoietic reconstitution after CD34+ cell transplantation in lethally irradiated SCID mice.

Integrin alphavbeta3 enhances β-catenin signaling in acute myeloid leukemia harboring Fms-like tyrosine kinase-3 internal tandem duplication mutations: implications for microenvironment influence on sorafenib sensitivity

Binding of leukemia cells to the bone marrow extracellular matrix (ECM) through integrins might influence drug response and the survival of acute myeloid leukemia (AML). However, the functions of integrin in AML are needed to be clarified. Data from The Cancer Genome Atlas (TCGA) were retrieved and integrin β3 (ITGB3) expression and prognostic significance for AML were analyzed. Integrin alphavbeta3 (αvβ3) in sorafenib sensitivity and signaling pathway of FLT3-ITD AML cells was evaluated in vitro. The level of ITGB3 expression was positively correlated with risk stratification and prognosis of AML patients, especially in cytogenetic-normal patients with Fms-like tyrosine kinase-3 internal tandem duplication (FLT3-ITD) mutation. Integrin αvβ3 decreased sorafenib sensitivity when co-culture of MV4-11 cells and bone marrow stromal cells (BMSCs), and it is crucial for osteopontin (OPN) induced sorafenib insensitivity in FLT3-ITD mutated AML cells. Mechanically, αvβ3 enhance β-catenin activation through phosphatidylinositol 3-kinase (PI3K)/Akt/Glycogen synthase kinase-3 beta (GSK3β) pathway. Moreover, genetic inhibition of β-catenin by shRNA could increase sorafenib sensitivity in MV4-11 cells. Taken together, our study revealed a novel mechanism in microenvironment influence on sorafenib sensitivity in AML with FLT3-ITD mutation that was caused by activating integrin αvβ3/PI3K/Akt/GSK3β/β-catenin pathway. Integrin αvβ3/β-catenin could be considered as a new therapeutic target for AML especially for FLT3-ITD mutated AML.

Is allogeneic transplantation really the best treatment for FLT3/ITD-positive acute myeloid leukemia? A systematic review.

Fetal liver tyrosine kinase 3 (FLT3)–internal tandem duplications (ITDs) has been used as a powerful adverse prognostic indicator for acute myeloid leukemia (AML) in any age group. Evidence is mixed regarding the effects of allogeneic transplantation (allo‐HSCT) in first complete remission (CR) for patients with FLT3/ITD AML. To fill this gap, this study provides a systematic review and meta‐analysis of patients with FLT3/ITD AML receiving HSCT. A search of PubMed, Embase, and OVID yielded 1706 abstracts, two researchers screening the trials based on inclusion and exclusion criteria, and assessed the methodology quality independently. Meta‐analysis showed that compared with chemotherapy, both allo‐HSCT and autologous hematopoietic cell transplantation (auto‐HSCT) can reduce the relapse rate (p < 0.01) and improve both the OS (p < 0.01) and DFS (p < 0.01). But when compared allo‐HSCT with auto‐HSCT, the OS (p = 0.27) and DFS (p = 0.19) have no statistical significance, and only the relapse indicator has statistical significance, p < 0.01. Based on the results, we can conclude that allo‐HSCT is an efficient therapy approach for patients with FLT3/ITD AML. Chemotherapy cannot change the poor prognosis. Auto‐HSCT can improve OS and DFS, but it cannot reduce the relapse rate.

Cost and outcome in stem cell collections in HLA-haplo identical/mismatched related transplantation with combined granulocyte-colony stimulating factor-mobilized blood and bone marrow for patients with hematologic malignancies

Unmanipulated HLA-haplo identical/mismatched related transplantation with combined granulocyte-colony stimulating factor-mobilized peripheral blood stem cells (G-PBSCs) and granulocyte-colony stimulating factor-mobilized bone marrow (G-BM) has been developed as an alternative transplantation strategy for patients without an HLA-matched related or unrelated donor. In this transplantation setting, the cost and outcome of stem cell collections have not been defined completely. The aim of this study was to compare the cost and outcome of stem cell collection in HLA-haplo identical/mismatched related transplantation with combined G-PBSCs and G-BM to the HLA-identical/matched transplantation with G-PBSCs alone for patients with hematologic malignancies. Hundred and fifty-two healthy donors received twice-daily granulocyte-colony stimulating factor (G-CSF) subcutaneously for 5 days. The PBSCs were collected on day 4 and 5 of G-CSF treatment for HLA-identical/matched transplantation from unrelated/related donors. The PBSC collections and BM harvests was performed on day 4 and 5 of G-CSF treatment for HLA-haplo identical/mismatched related transplantation from related donors, respectively. There was no difference in the major characteristics between groups. More stem cells were harvested in HLA-haplo identical/mismatched related donors than that of HLA-identical/matched donors and a lower cost was seen in the former. The HLA-haplo identical/mismatched related transplantation with combined G-PBSCs and G-BM was a feasible approach with high cell harvest and low cost of stem cell collection for patients with hematologic malignancies.

AMD3100 and G-CSF disrupt the cross-talk between leukemia cells and the endosteal niche and enhance their sensitivity to chemotherapeutic drugs in biomimetic polystyrene scaffolds

BACKGROUND The multidrug resistance of leukemia cells is closely related to the microenvironment. The present leukemia microenvironment models focus on two-dimensional co-culture system in vitro which does not mimic the in vivo cell growth, while the 3D polystyrene (PS) scaffolds have the advantage. Stromal cell derived factor-1 may be involved in the shielding of endosteal niche from leukemia cells by binding to its receptor CXCR4, but the relationship between SDF-1/CXCR4 axis and leukemia cells is unclear. DESIGN AND METHODS The experiments were built on the 3D PS scaffolds coated with osteoblasts. Stromal cells and MV4-11 cells were plated on the scaffolds. Then G-CSF, AMD3100 and cytarabine were added. Adhesive rate, SDF-1 level, migration state, apoptosis rate, and cell cycle of leukemia cells were observed after incubation at 24h and 48h. RESULTS G-CSF decreased the level of SDF-1 and inhibited the expression of CXCR4 and promoted stationary phase leukemia cells to enter the mitotic phase and enhanced the killing effect of chemotherapeutic drugs. AMD3100 disrupted the interaction between tumors and matrix, mobilized the leukemia cells to keep away from the protective microenvironment and strengthened the cytotoxic effect of Ara-C. The combination of G-CSF and AMD3100 had stronger effects on killing the leukemia cells induced by Ara-C. CONCLUSION It demonstrates that AMD3100 and G-CSF may inhibit adhesion and migration abilities of leukemia cells with the bone marrow niche. Both of them inhibit the role of SDF-1/CXCR4 directly or indirectly. Thus inhibiting SDF-1/CXCR4 axis may be helpful to the treatment of refractory AML.

Are there any new insights for G-CSF and/or AMD3100 in chemotherapy of haematological malignants?

AML is a common life-threatening blood system malignancy. The treatment of AML continues to face greater challenges. An abnormal haematopoietic niche with high adhesion and proliferation might be the root cause of resistance and relapse. Most leukaemia cells are stored in the endosteal niche and recess in the G0 phase, and they are not sensitive to varieties of radiotherapies and chemotherapies. G-CSF and AMD3100 are increasingly used in priming chemotherapy. G-CSF can promote leukaemia cells to the cell cycle, which improves the complete remission rate of leukaemia patients. AMD3100, the novel CXCR4 antagonist, could also potentially promote leukaemia cells to cell cycle and improve the susceptibility of leukaemia cells to chemotherapeutic agents. The combination of them enhances anti-leukaemia effect. So in this review, we explore the function of G-CSF and/or AMD3100 in the priming chemotherapy of haematological malignants.

Effects of anti-CXCR4 monoclonal antibody 12G5 on proliferation and apoptosis of human acute myelocytic leukemia cell line HL-60

Objective To investigate the expression of CXCR4 on HL-60 cell line and the proliferation. apoptosis of HL-60 cell line cocultured with bone marrow stromal cells, so as to assess the possibility of 12G5, an anti-CXCR4 monoclonal antibody, in eradicating the minimal residual disease.

Extramedullary T-lymphoblastic blast crisis in chronic myelogenous leukemia: A case report of successful diagnosis and treatment.

Extramedullary T-lymphoblastic blast crisis of chronic myelogenous leukemia (CML) is uncommon and the prognosis is poor. It was usually misdiagnosed as the co-existence of T-lymphoblastic lymphoma (T-LBL) and CML. In the present study, we report a patient with CML, who developed extramedullary T-lymphoblastic blast crisis and was successfully treated with human leukocyte antigen (HLA)-mismatched stem cell transplantation. The patient was a 44-year-old man who presented with lymphadenectasis and leucocytosis prior to diagnosis. The bone marrow smear, biopsy and fluorescence in situ hybridization (FISH) of Breakpoint Cluster Region/ Abelson murine leukaemia (BCR/ABL) supported the diagnosis of CML in the chronic phase, while the immunohistochemistry of lymph nodes supported the diagnosis of T-LBL. The FISH test for BCR/ABL in lymph node blast cells was performed and the result was positive; therefore, the patient was diagnosed with extramedullary T-lymphoblastic blast crisis of CML. After several courses of combined chemotherapy, the patient was treated with HLA-mismatched stem cell transplantation and obtained continuous remission for 51 months until the present (September 2013).