Idarubicin-Intensified Hematopoietic Cell Transplantation Improves Relapse and Survival of High-Risk Acute Leukemia Patients with Minimal Residual Disease.

The optimal conditioning regimen of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for high-risk patients with minimal residual disease (MRD) remains controversial. We studied the results in 98 high-risk acute leukemia patients transplanted with idarubicin (IDA)-intensified conditioning regimens between 2012 January and 2017 January. Among these patients, 31 (31.6%) had more than 5% marrow blasts at time of transplantation and 67 patients were in morphologic remission: MRD negative status at time of conditioning was achieved in 39 patients (39.8%), whereas 28 (28.6%) remained carriers of any other positive MRD level in the bone marrow. Three-year relapse estimates of patients with MRD-positive remission was 22.0%, which was remarkably lower than patients with active disease (45.4%, P = .027) but approximate to that of patients in MRD-negative remission (15.5%, P = .522). There were no significant differences in terms of 3-year estimated overall survival (OS) and disease-free survival (DFS) between MRD-positive remission and MRD-negative remission groups (71.4% versus 79.1% [P = .562] and 67.9% versus 76.9% [P = .634], respectively). Moreover, the estimated rates of 3-year OS and DFS of patients in MRD-positive remission were significantly better than those in patients with active disease (71.4% versus 41.9% [P = .033] and 67.9% versus 38.7% [P = .037], respectively). These data indicate that IDA-intensified conditioning allo-HSCT could overcome the negative prognostic impact of MRD.

[Effect of Carvacrol on the Biological Behavior of Leukemia Cells and Its Mechanism].

OBJECTIVE: To explore the effect of carvacrol on the biological behavior of leukemia cells and its regulation to circ-0008717/miR-217 molecular axis. METHODS: Human acute lymphoblastic leukemia cells Molt-4 were cultured in vitro, and different concentrations of carvacrol were added to the cells. si-NC and si-circ-0008717 were transfected into Molt-4 cells (si-NC group, si-circ-0008717 group). pcDNA, pcDNA-circ-0008717, anti-miR-NC, anti-miR-217 were transfected into Molt-4 cells and then added to carvacrol-treated cells (carvacrol+pcDNA group, carvacrol+pcDNA-circ-0008717 group, carvacrol+anti-miR-NC group, carvacrol+anti-miR-217 group). MTT, plate clone formation experiment, and flow cytometry were used to detect the viability of the cell, colony formation number, and apoptosis rate of cells, respectively. The RT-qPCR method was used to detect the expression levels of circ-0008717 and miR-217. The dual luciferase reporter gene experiment was used to detect the targeting relationship between circ-0008717 and miR-217. RESULTS: After carvacrol treatment, the cell viability decreased significantly (r=-0.9405), expression level of circ-0008717 decreased (r=-0.9117), colonies formed number decreased (r=-0.9256), while the cell apoptosis rate increased (r= 0.8464), and the expression level of miR-217 increased (r=0.9468). Compared with the si-NC group, the expression level of miR-217 in si-circ-0008717 group increased (P＜0.001), the cell apoptosis rate increased (P＜0.001), while cell viability decreased (P＜0001), the number of colonies formed decreased (P＜0.001). Compared with the carvacrol+pcDNA group, the cell viability of the carvacrol+pcDNA-circ-0008717 group increased (P＜0.001), the number of colonies formed increased (P＜0.001), while the cell apoptosis rate decreased (P＜0.001). circ-0008717 could target miR-217. The cell viability of the carvacrol+anti-miR-217 group increased (P＜0.001), and the number of colonies formed increased (P＜0.001), while the cell apoptosis rate decreased (P＜0001) as compared with the carvacrol+anti-miR-NC group. CONCLUSION: Carvacrol can promote the expression of miR-217 by down-regulating the expression of circ-0008717, thereby reducing the proliferation and cloning ability of leukemia cells and promoting cell apoptosis.

[Expression and Clinical Significance of MMSA-8 and MMSA-1 in Bone Marrow of Patients with M2 Acute Myeloid Leukemia].

OBJECTIVE: To detect the expression of multiple myeloma-associated antigen (MMSA)-8 and MMSA-1 in bone marrow mononuclear cells of patients with acute myeloid leukemia, and explore their roles in acute myeloid leukemia. METHODS: A total of 83 patients with M2 acute myeloid leukemia in our hospital from January 2019 to January 2020 were selected as research group, during the same period, 15 patients diagnosed iron deficiency anemia were selected as control group. Real-time fluorescence quantitative PCR was used to detect the levels of MMSA-8 and MMSA-1 in bone marrow mononuclear cells. Patients in the research group were divided into remission and non remission according to the clinical curative effect, and were divided into good prognosis, medium prognosis, and poor prognosis according to the prognosis. The relationship between MMSA-8, MMSA-1 and clinical efficacy, prognosis was analyzed. In addition, the general data of patients in the research group were collected, including white blood cell count (WBC), hemoglobin (Hb), platelet count (PLT), and percentage of bone marrow progenitor cells at admission. Pearson method was used to analyze the correlation between MMSA-8, MMSA-1 and clinical data, and MMSA-8 and MMSA-1. RESULTS: The analysis results about mRNA levels of MMSA-8 and MMSA-1 in bone marrow mononuclear cells of patients showed that patients in the research group were significantly higher than those in the control group (P<0.05); In the research group, patients without remission were also significantly higher than those with remission, as well as those with medium and poor prognosis than with good prognosis, while only mRNA level of MMSA-1 in patients with poor prognosis was significantly higher than those with medium prognosis (P<0.05). Pearson analysis showed that MMSA-8, MMSA-1 were positively correlated with WBC (r=0.468, r=0.516), and MMSA-8 was positively correlated with MMSA-1 (r=0.318). CONCLUSION: The levels of MMSA-8 and MMSA-1 in bone marrow mononuclear cells of patients with M2 acute myeloid leukemia are increased, which are closely related to the occurrence and development of the disease, and have certain value for the prognosis.

High efficacy and safety of CD38 and BCMA bispecific CAR-T in relapsed or refractory multiple myeloma.

BACKGROUND: B-cell maturation antigen (BCMA) chimeric antigen receptor T (CAR-T) cell therapy has obtained promising results in relapsed or refractory multiple myeloma (R/R MM), while some patients do not response, or relapse in short term after treatment. Combining with anti-CD38 might solve the problem of targeting BCMA alone. We aimed to assess the efficacy and safety of BCMA and CD38 (BCMA-CD38) bispecific CAR-T cells in R/R MM patients. METHODS: We did a single-center, single-arm clinical study at the Second Affiliated Hospital of Yangtze University in China. Patients meeting with the inclusion criteria were administered with fludarabine and cyclophosphamide before CAR-T cells infusion. Response and adverse events were assessed after infusion. This study was registered with the Chinese Clinical Trial Registration Center (ChiCTR1900026286). RESULTS: First, we found BCMA-CD38 CAR-T cells exhibited enhanced killing effect on BCMA+CD38+ cells in vitro, compared to BCMA CAR-T and CD38 CAR-T cells. We further demonstrated its anti-tumor activity in vivo. Then, we enrolled 16 R/R MM patients for safety and efficacy analyses. Of the 16 evaluable patients, 14 (87.5%) respond to the treatment, including 13 stringent complete response (sCR) and one partial response (PR), while two patients did not respond. At a median follow-up of 11.5 months, of the 13 patients who achieved sCR, 76.9% (10/13) did not relapse or progress during follow-up. Relapse occurred in 3 patients (Patient 2, 3 and 4) after achieving sCR. In sum, four patients died, of which one died of hemophagocytic lymphohistiocytosis syndrome secondary to severe cytokine release syndrome (CRS) and three died of disease progression or relapse. The 1-year progression-free survival rates was 68.8%. The 1-year overall survival rate was 75.0%. Extramedullary lesions were eliminated in 62.5% (5/8) patients. The most common symptoms after CAR-T infusion were cytopenia (16, 100%), fever (10, 62.5%), fatigue (8, 50.0%) and myalgias (8, 50.0%). Twelve patients (75.0%) were observed with various grades of CRS, of which five patients (31.3%) got serious CRS (Grade ≥ 3). The CAR+ cell expansion levels were associated with the severity of CRS. Transient clonal isotype switch was observed after CAR-T infusion. CONCLUSION: Our results confirm that BCMA-CD38 CAR-T cells therapy is feasible in treating R/R MM patients, with high response rate, low recurrence rate and manageable CRS, which will be a promising treatment option for R/R MM. TRIAL REGISTRATION: ChiCTR1900026286, registered on September 29, 2019, retrospectively registered, URL: https://www.chictr.org.cn/showproj.aspx?proj=43805.

Inhibition of the miR-155 and protein prenylation feedback loop alleviated acute graft-versus-host disease through regulating the balance between T helper 17 and Treg cells.

MicroRNA-155(miR-155) and protein prenylation have been reported to participate in acute graft-versus-host disease (aGVHD) through modulating T lymphocyte differentiation, however the mechanism remains elusive. In this study, we found that the expression of miR-155 and protein prenyltransferases in peripheral blood T lymphocytes of aGVHD mice was significantly increased. Suppression of miR-155 by antagomir-155 could remarkably reduce prenyltransferases mRNA and protein expression in T lymphocytes of aGVHD mice. Conversely, prenyltransferase inhibitors significantly reduced the level of miR-155. Inhibition of this feedback loop of miR-155 and protein prenylation in aGVHD mice led to improved survival and lower aGVHD histopathology scores and significantly induced T cell deficient differentiation towards T helper 17 (Th17) cells and titled differentiation towards CD4+CD25hi regulatory T (Treg) cells. Furthermore, the immunoregulatory effects and protection from aGVHD of prenyltransferase inhibitors could be reversed by the addition of miR-155. The dual treatment of prenylation inhibitors and antagomir-155 showed synergistic effects on T polarization and protection from aGVHD. Consistent with the in vivo changes, inhibition of this feedback loop of miR-155 and protein prenylation affected Th17 and Treg cell polarization in vitro. Our data suggest that miR-155 and protein prenylation may constitute a feedback loop that amplifies immune and inflammatory responses in subjects with aGVHD, and they may serve as potential targets for aGVHD prophylaxis and treatment.

piRNA-823 delivered by multiple myeloma-derived extracellular vesicles promoted tumorigenesis through re-educating endothelial cells in the tumor environment.

Extracellular vesicles (EVs) can carry a wide array of RNAs in the tumor microenvironment, and are crucial for communication between tumor and surrounding stromal cells, including endothelial cells. Piwi-interacting RNAs (piRNAs) are important regulators implicated in the pathogenesis of multiple myeloma (MM). However, little is understood about the role of piRNA-823 in intercellular communication between MM and endothelial cells. In this study, we found that piRNA-823 mainly accumulated in EVs from peripheral blood of MM patients and EVs derived from MM cells (MM-derived-EVs). Increased piRNA-823 expression was associated with late stages and poor prognosis of MM. The MM-derived-EVs effectively transferred piRNA-823 to EA.hy926 endothelial cells. The piRNA-823 mimic and inhibitor were designed to upregulate or to suppress the endogenous function of piRNA-823. Transfection with piRNA-823 mimic or treatment with MM-derived-EVs significantly promoted the proliferation, tube formation, and invasion of EA.hy926 cells by enhancing the expression of VEGF, IL-6, and ICAM-1 and attenuating apoptosis. EA.hy926 cells transfected with piRNA-823 mimic or pre-treated with MM-derived-EVs promoted the growth of xenograft MM in mice. In contrast, the transfection with piRNA-823 inhibitor or treatment with EVs from piRNA-823 inhibitor-transfected-MM cells had diametrically opposite effects. Our findings demonstrated that piRNA-823 carried by MM-derived-EVs is essential for the re-education of ECs toward a unique environment amenable to the growth of MM cells by altering its biological characteristics. Our findings may pave the way for the development of new piRNA-mediated prognostic stratification and therapeutic strategies for MM.

Endothelial microparticles delivering microRNA-155 into T lymphocytes are involved in the initiation of acute graft-versus-host disease following allogeneic hematopoietic stem cell transplantation.

Endothelial microparticles (EMPs) upregulation has been observed in acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, the role of EMPs remains unclear. We found that EMPs derived from TNF-α-stimulated human umbilical vein endothelial cells (EA.hy926) concentrated more microRNA-155 (miR-155) compared with maternal cells. The miR-155 levels in MPs from peripheral blood of aGVHD patients and mice were remarkably elevated and significantly higher than the levels in plasma. Moreover, the rising peak of miR-155 in MPs occurred significantly prior to the peak in T lymphocytes. Additionally, we observed fluorescently-labeled miR-155 in EMPs actively transported into recipient T lymphocytes. Inhibition of miR-155 in EMPs by antagomir-155 did not influence the proliferation and apoptosis of T lymphocytes, but induced defective differentiation toward Th1, Th9 and Th17 cells and skewed differentiation toward Th2 and Treg cells. Furthermore, intravenous injection of miR-155-deficient-EMPs into aGVHD mice significantly attenuated the exacerbation of aGVHD manifestations and abnormal T lymphocytes differentiation induced by high concentration EMPs. Taken together, these data provide a mechanistic framework in which miR-155 delivered by EMPs is involved in aGVHD pathogenesis by activating specific T lymphocytes functions. The results may provide new therapeutic approaches for aGVHD while preserving graft-versus-leukemia (GVL) effect.

Correction: Endothelial microparticles delivering microRNA-155 into T lymphocytes are involved in the initiation of acute graft-versus-host disease following allogeneic hematopoietic stem cell transplantation.

[This corrects the article DOI: 10.18632/oncotarget.15579.].