Compassionate use of roxadustat for treatment of refractory renal anemia in an infant.

BACKGROUND: Erythropoiesis-stimulating agents (ESAs) have played an important role in the treatment of renal anemia in children, but cannot improve hemoglobin to target level in some cases. Roxadustat, a hypoxia-inducible factor prolyl hydroxylase inhibitor, can stimulate endogenous erythropoietin production and regulate iron metabolism even in patients with kidney failure. However, roxadustat has not yet been approved for use in children. CASE-DIAGNOSIS/TREATMENT: We report a case of refractory renal anemia in an 80-day-old boy, who was hyporesponsive to ESAs even in combination with iron supplementation and transfusion. Compassionate use of roxadustat successfully corrected the intractable anemia. Hyperkalemia is a manageable adverse event of concern during follow-up. CONCLUSION: The successful experience in this case may inform the clinical utility of roxadustat for refractory renal anemia in children, which should be further confirmed by well-designed prospective clinical trials.

hUC-MSCs Attenuate Acute Graft-Versus-Host Disease through Chi3l1 Repression of Th17 Differentiation.

Mesenchymal stem cells (MSCs) have already demonstrated definitive evidence of their clinical benefits in acute graft-versus-host disease (aGvHD) and other inflammatory diseases. However, the comprehensive mechanism of MSCs' immunomodulation properties has not been elucidated. To reveal their potential immunosuppressive molecules, we used RNA sequencing to analyze gene expression in different tissue-derived MSCs, including human bone marrow, umbilical cord, amniotic membrane, and placenta, and found that chitinase-3-like protein 1 (Chi3l1) was highly expressed in human umbilical cord mesenchymal stem cells (hUC-MSCs). We found that hUC-MSCs treated with interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) exhibited increased expression of Chi3l1 and concurrently repressed T-helper 17 cell (Th17) differentiation through inhibition of signal transducer and activator of transcription 3 (STAT3) activation. Furthermore, Chi3l1 knockdown hUC-MSCs exhibited impaired therapeutic efficacy in aGvHD mice with an increased inflammatory response by promoting Th17 cell differentiation, including an increase in IL-17A in the spleen, intestine, and serum. Collectively, these results reveal a new immunosuppressive molecule, Chi3l1, in hUC-MSCs in the treatment of aGvHD that regulates Th17 differentiation and inhibits STAT3 activation. These novel insights into the mechanisms of hUC-MSC immunoregulation may lead to the consistent production of hUC-MSCs with strong immunosuppressive functions and thus improved clinical utility.

Myelodysplastic syndromes are multiclonal diseases derived from hematopoietic stem and progenitor cells.

Myelodysplastic syndromes (MDS) are generally considered as a group of clonal diseases derived from hematopoietic stem cells, but a number of studies have suggested that they are derived from myeloid progenitor cells. We aimed to identify the cell of origin in MDS by single-cell analyses. Targeted single-cell RNA sequencing, covering six frequently mutated genes (U2AF1, SF3B1, TET2, ASXL1, TP53, and DNMT3A) in MDS, was developed and performed on individual cells isolated from the CD34+ and six lineage populations in the bone marrow of healthy donors (HDs) and patients with MDS. The detected mutations were used as clonal markers to define clones. By dissecting the distribution of clones in six lineages, the clonal origin was determined. We identified three mutations both in HDs and patients with MDS, termed clonal hematopoiesis (CH) mutations. We also identified fifteen mutations only detected in patients with MDS, termed MDS mutations. Clonal analysis showed that CH clones marked by CH mutations and MDS clones marked by MDS mutations were derived from hematopoietic stem cells as well as various hematopoietic progenitor cells. Most patients with MDS showed the chimeric state with CH clones and MDS clones. Clone size analysis suggested that CH mutations may not contribute to clonal expansion of MDS. In conclusion, MDS comprise multiple clones derived from hematopoietic stem and progenitor cells.

Multiple cells of origin in common with various types of mouse N-Myc acute leukemia.

Little is known regarding whether the cell of origin differs among different leukemia types. To address this fundamental issue, we determined the cell of origin in five distinct types of acute leukemia induced by N-Myc overexpression in mice. CD150+CD48-CD41-CD34-c-Kit+Sca-1+Lin- (KSL) (HSC1) cells, CD150-CD48-CD41-CD34-KSL (HSC2) cells, CD150+CD41+CD34-KSL (HPC1) cells, CD150+CD41+CD34+KSL (HPC2) cells, and CD150-CD41-CD34+KSL (HPC3) cells were purified from the bone marrow of adult C57BL/6 mice, transduced with the N-Myc retrovirus vector, and transplanted into lethally irradiated mice. B-cell acute lymphoblastic leukemia (B-ALL), T-cell acute lymphoblastic leukemia (T-ALL), acute myeloid leukemia (AML), acute undifferentiated leukemia (AUL), and mixed phenotype acute leukemia (MPAL) developed from five populations. RNA sequencing data supported the phenotypical diagnoses of leukemia, except that AUL appeared transcriptionally close to T-ALL. Whole-genome sequencing revealed that retroviral integration sites were irrelevant to the leukemia types and that T-ALL and AML of MPAL shared the same integration site and many gene mutations, suggesting their common origin. Additionally, leukemic stem cells were identified in the KSL cell population, suggesting that the phenotypes of leukemic stem cells are irrelevant to leukemia types. This study provides experimental evidence for the similar and multiple cells of origin in acute leukemia.

Gene knockout in highly purified mouse hematopoietic stem cells by CRISPR/Cas9 technology.

The CRISPR/Cas9 system has been used for genome editing of human and mouse cells. In this study, we established a protocol for gene knockout (KO) in mouse hematopoietic stem cells (HSCs). HSCs were highly purified from the bone marrow of tamoxifen-treated Cas9-EGFP/Cre-ER transgenic mice, maintained in serum-free polyvinyl alcohol culture with cytokines, lentivirally transduced with sgRNA-Crimson, and transplanted into lethally irradiated mice with competitor cells. Previous studies of Pax5 KO mice have shown B cell differentiation block. To verify our KO HSC strategy, we deleted Pax5 gene in 600 CD201+CD150+CD48-c-Kit+Sca-1+Lin- cells (HSC1 cells), highly enriched in myeloid-biased HSCs, and CD201+CD150-CD48- c-Kit+Sca-1+Lin- cells (HSC2 cells), highly enriched in lymphoid-biased HSCs. As predicted, both Pax5 KO HSC1 and HSC2 cells showed few B cells in the peripheral blood and the accumulation of pro-B cells in the bone marrow of recipient mice. Our data suggesetd that myeloid-biased and lymphoid-biased HSCs share a common B cell differentiation pathway. This population-specific KO strategy will find its applications for gene editing in a varity of somatic cells, particuarly rare stem and progenitor cells from different tissues.

Analysis and Isolation of Mouse Leukemic Stem Cells.

Flow cytometry has been widely used in basic and clinical research for analysis of a variety of normal and malignant cells. Hematopoietic stem cells (HSCs) and leukemic stem cells (LSCs) can be highly purified by flow cytometry. Isolated HSCs and LSCs can be functionally identified by transplantation assays and can also be studied at the molecular level. Here we describe the flow cytometry methods for analysis and isolation of mouse HSCs and LSCs.

Genetic Architecture of Childhood Kidney and Urological Diseases in China.

Kidney disease is manifested in a wide variety of phenotypes, many of which have an important hereditary component. To delineate the genotypic and phenotypic spectrum of pediatric nephropathy, a multicenter registration system is being implemented based on the Chinese Children Genetic Kidney Disease Database (CCGKDD). In this study, all the patients with kidney and urological diseases were recruited from 2014 to 2020. Genetic analysis was conducted using exome sequencing for families with multiple affected individuals with nephropathy or clinical suspicion of a genetic kidney disease owing to early-onset or extrarenal features. The genetic diagnosis was confirmed in 883 of 2256 (39.1%) patients from 23 provinces in China. Phenotypic profiles showed that the primary diagnosis included steroid-resistant nephrotic syndrome (SRNS, 23.5%), glomerulonephritis (GN, 32.2%), congenital anomalies of the kidney and urinary tract (CAKUT, 21.2%), cystic renal disease (3.9%), renal calcinosis/stone (3.6%), tubulopathy (9.7%), and chronic kidney disease of unknown etiology (CKDu, 5.8%). The pathogenic variants of 105 monogenetic disorders were identified. Ten distinct genomic disorders were identified as pathogenic copy number variants (CNVs) in 11 patients. The diagnostic yield differed by subgroups, and was highest in those with cystic renal disease (66.3%), followed by tubulopathy (58.4%), GN (57.7%), CKDu (43.5%), SRNS (29.2%), renal calcinosis /stone (29.3%) and CAKUT (8.6%). Reverse phenotyping permitted correct identification in 40 cases with clinical reassessment and unexpected genetic conditions. We present the results of the largest cohort of children with kidney disease in China where diagnostic exome sequencing was performed. Our data demonstrate the utility of family-based exome sequencing, and indicate that the combined analysis of genotype and phenotype based on the national patient registry is pivotal to the genetic diagnosis of kidney disease. Supplementary Information: The online version contains supplementary material available at 10.1007/s43657-021-00014-1.

Lymphoid-biased hematopoietic stem cells and myeloid-biased hematopoietic progenitor cells have radioprotection activity.

Radioprotection was previously considered as a function of hematopoietic stem cells (HSCs). However, recent studies have reported its activity in hematopoietic progenitor cells (HPCs). To address this issue, we compared the radioprotection activity in 2 subsets of HSCs (nHSC1 and 2 populations) and 4 subsets of HPCs (nHPC1-4 populations) of the mouse bone marrow, in relation to their in vitro and in vivo colony-forming activity. Significant radioprotection activity was detected in the nHSC2 population enriched in lymphoid-biased HSCs. Moderate radioprotection activity was detected in nHPC1 and 2 populations enriched in myeloid-biased HPCs. Low radioprotection activity was detected in the nHSC1 enriched in myeloid-biased HSCs. No radioprotection activity was detected in the nHPC3 and 4 populations that included MPP4 (LMPP). Single-cell colony assay combined with flow cytometry analysis showed that the nHSC1, nHSC2, nHPC1, and nHPC2 populations had the neutrophils/macrophages/erythroblasts/megakaryocytes (nmEMk) differentiation potential whereas the nHPC3 and 4 populations had only the nm differentiation potential. Varying day 12 spleen colony-forming units (day 12 CFU-S) were detected in the nHSC1, nHSC2, and nHPC1-3 populations, but very few in the nHPC4 population. These data suggested that nmEMk differentiation potential and day 12 CFU-S activity are partially associated with radioprotection activity. Reconstitution analysis showed that sufficient myeloid reconstitution around 12 to 14 days after transplantation was critical for radioprotection. This study implied that radioprotection is specific to neither HSC nor HPC populations, and that lymphoid-biased HSCs and myeloid-biased HPCs as populations play a major role in radioprotection.

Clinical Features and Prognostic Impact of Coexpression Modules Constructed by WGCNA for Diffuse Large B-Cell Lymphoma.

OBJECTIVE: Diffuse large B-cell lymphoma (DLBCL) is a highly aggressive malignant tumor, accounting for 30-40% of non-Hodgkin's lymphoma. Our aim was to construct novel prognostic models of candidate genes based on clinical features. METHODS: RNA-seq and clinical data of DLBCL were retrieved from TCGA database. Coexpression modules were constructed by WGCNA. Then, we investigated the interactions between modules and clinical features. By overall survival analysis, prognostic candidate genes from modules of interest were identified. A coexpression network of prognostic candidate genes was then constructed through WGCNA. GEPIA was used to analyze the expression of a candidate gene between DLBCL and normal samples. RESULTS: 19 coexpression modules were constructed by 12813 genes from 52 DLBCL samples. The number of genes in modules ranged from 34 to 5457. We found that the purple module was significantly related with histological type (p value = 1e-04). Overall survival analysis revealed that MAFA-AS1, hsa-mir-338, and hsa-mir-891a were related with prognosis of DLBCL (p value = 0.027, 0.039, and 0.022, respectively). A coexpression network was constructed for the three prognostic genes. MAFA-AS1 was interacted with 36 genes, hsa-mir-891a was interacted with 11 genes, while no gene showed interaction with hsa-mir-338. Using GEPIA, we found that MAFA-AS1 showed low expression in DLBCL samples (p < 0.01). CONCLUSION: We constructed a coexpression module related with histological type and identified three candidate genes (MAFA-AS1, hsa-mir-338, and hsa-mir-891a) that possessed potential value as prognostic biomarkers and therapeutic targets of DLBCL.

rhTPO combined with chemotherapy and G-CSF for autologous peripheral blood stem cells in patients with refractory/relapsed non-Hodgkin's lymphoma.

OBJECTIVE: The mobilization and collection of sufficient autologous peripheral blood stem cells (APBSCs) are important for the fast and sustained reconstruction of hematopoietic function after autologous transplantation. This study aims to evaluate the mobilization effect and safety of thrombopoietin (TPO) combined with chemotherapy + G-CSF for APBSCs in patients with refractory/relapsed non-Hodgkin's lymphoma. METHODS: A total of 78 patients were included in the present study. After receiving mobilization chemotherapy, all patients were randomly divided into two groups: TPO group (n=40), patients were given subcutaneous injection of rhTPO + G-CSF, and control group (n=38), patients were given subcutaneous injection of G-CSF. The primary endpoint was the total number of obtained CD34+ cells. The secondary endpoints were the mononuclear cell count, the proportion of target and minimum mobilization, the engraftment time of neutrophils and platelets after APBSCT, the number of platelet and red blood cell infusions, the incidence of infectious fever and fever duration, and TPO-related side effects in patients. RESULTS: TPO participation significantly increased the total CD34+ cell count. A higher proportion of patients in the TPO group achieved the minimum and target CD34+ cells, when compared to the control group. TPO-related adverse events were not observed in either of these groups. In addition, there were no significant differences in engraftment time, the number of platelet and red blood cell transfusions, the incidence of infectious fever, and fever duration between these two groups. CONCLUSION: TPO combined with chemotherapy + G-CSF can safely and effectively enhance the mobilization effect for APBSCs in patients with refractory/relapsed non-Hodgkin's lymphoma.

Genetic spectrum of renal disease for 1001 Chinese children based on a multicenter registration system.

To explore the approaches and diagnostic yield of genetic testing for renal disease in children, we describe the genotype and phenotype of the national cohort of children with renal disease from 13 different regions of China recruited from 2014 to 2018 by building up the multicenter registration system (Chinese Children Genetic Kidney Disease Database, CCGKDD). Genetic diagnosis was confirmed in 42.1% of our cohort of 1001 pediatric patients with clinical suspicion of a genetic renal disease. Of the 106 distinct monogenetic disorders detected, 15 accounted for 60.7% of genetic diagnoses. The diagnostic yield was 29.1% in steroid resistant nephritic syndrome (SRNS), 61.4% in cystic renal disease, 17.0% in congenital anomalies of the kidney and urinary tract (CAKUT), 62.3% in renal tubular disease/renal calcinosis, and 23.9% for chronic kidney disease (CKD) 3 to 5 stage with unknown origin. Genetic approaches of target gene sequence (TGS), singleton whole-exome sequencing (WES) and trio-WES were performed with diagnostic rates of 44.8%, 36.2%, and 42.6%, respectively. The early use of trio-WES could improve the diagnostic rate especially in renal tubular disease and calcinosis. We report the genetic spectrum of Chinese children with renal disease. Establishment of the CCGKDD will improve the genetic work on renal disease.

Lineage marker expression on mouse hematopoietic stem cells.

Whether hematopoietic stem cells (HSCs) express lineage markers is controversial. In this study, we highly purified HSCs from the adult bone marrow of C57BL/6 mice and examined their gene expression and reconstitution potential. We first focused on the integrin family. Single-cell reverse transcription polymerase chain reaction revealed that the expression of ItgaM/Itgb2 (Mac-1) and Itga2b/Itgb3 (CD41/CD61) gradually increased along HSC differentiation, whereas Itga4, Itga5, Itga6, and ItgaV (CD51) together with Itgb1 were highly expressed in both HSCs and hematopoietic progenitor cells (HPCs). We next fractionated HSCs based on their expression of Mac-1, CD41, and CD51 by flow cytometry. We detected Mac-negative and Mac-low, but not Mac-high cells, in the HSC population. We also detected CD41-negative, -low, and -high cells in the HSC population. Competitive repopulation revealed that Mac-1-negative and -low HSCs were functionally similar, and CD41-negative and -low HSCs were functionally similar, at the single-cell level, but CD41-high HSCs were not detectable. We then found that the selection of Mac-1-negative HSCs or CD41-negative HSCs had no advantage in HSC purification. We moreover found that HSCs expressed more CD51 than CD41, and HPCs expressed more CD41 than CD51, suggesting that CD51 expression was gradually replaced by CD41 expression during megakaryocyte differentiation. We concluded that low levels of Mac-1 and CD41 expression are irrelevant to the self-renewal and differentiation potentials in HSCs.

Mouse acute leukemia develops independent of self-renewal and differentiation potentials in hematopoietic stem and progenitor cells.

The cell of origin, defined as the normal cell in which the transformation event first occurs, is poorly identified in leukemia, despite its importance in understanding of leukemogenesis and improving leukemia therapy. Although hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) were used for leukemia models, whether their self-renewal and differentiation potentials influence the initiation and development of leukemia is largely unknown. In this study, the self-renewal and differentiation potentials in 2 distinct types of HSCs (HSC1 [CD150+CD41-CD34-Lineage-Sca-1+c-Kit+ cells] and HSC2 [CD150-CD41-CD34-Lineage-Sca-1+c-Kit+ cells]) and 3 distinct types of HPCs (HPC1 [CD150+CD41+CD34-Lineage-Sca-1+c-Kit+ cells], HPC2 [CD150+CD41+CD34+Lineage-Sca-1+c-Kit+ cells], and HPC3 [CD150-CD41-CD34+Lineage-Sca-1+c-Kit+ cells]) were isolated from adult mouse bone marrow, and examined by competitive repopulation assay. Then, cells from each population were retrovirally transduced to initiate MLL-AF9 acute myelogenous leukemia (AML) and the intracellular domain of NOTCH-1 T-cell acute lymphoblastic leukemia (T-ALL). AML and T-ALL similarly developed from all HSC and HPC populations, suggesting multiple cellular origins of leukemia. New leukemic stem cells (LSCs) were also identified in these AML and T-ALL models. Notably, switching between immunophenotypical immature and mature LSCs was observed, suggesting that heterogeneous LSCs play a role in the expansion and maintenance of leukemia. Based on this mouse model study, we propose that acute leukemia arises from multiple cells of origin independent of the self-renewal and differentiation potentials in hematopoietic stem and progenitor cells and is amplified by LSC switchover.

Interleukin-12 supports in vitro self-renewal of long-term hematopoietic stem cells.

Hematopoietic stem cells (HSCs) self-renew or differentiate through division. Cytokines are essential for inducing HSC division, but the optimal cytokine combination to control self-renewal of HSC in vitro remains unclear. In this study, we compared the effects of interleukin-12 (IL-12) and thrombopoietin (TPO) in combination with stem cell factor (SCF) on in vitro self-renewal of HSCs. Single-cell assays were used to overcome the heterogeneity issue of HSCs, and serum-free conditions were newly established to permit reproduction of data. In single-cell cultures, CD150+CD48-CD41-CD34-c-Kit+Sca-1+lineage- HSCs divided significantly more slowly in the presence of SCF+IL-12 compared with cells in the presence of SCF+TPO. Serial transplantation of cells from bulk and clonal cultures revealed that TPO was more effective than IL-12 at supporting in vitro self-renewal of short-term (<6 months) HSCs, resulting in a monophasic reconstitution wave formation, whereas IL-12 was more effective than TPO at supporting the in vitro self-renewal of long-term (>6 months) HSCs, resulting in a biphasic reconstitution wave formation. The control of division rate in HSCs appeared to be crucial for preventing the loss of self-renewal potential from their in vitro culture.

Low-dose anti-thymocyte globulin plus low-dose posttransplant cyclophosphamide as graft-versus-host disease prophylaxis in haploidentical peripheral blood stem cell transplantation combined with unrelated cord blood for patients with hematologic malignancies: a prospective, phase II study.

Nowadays, the most wildly used regimens for graft-versus-host disease (GvHD) prophylaxis in haplo-hematopoietic stem cell transplantation (Haplo-HSCT) are based on in vivo T-cell depletion (TCD) with anti-thymocyte globulin (ATG) or posttransplant cyclophosphamide (PTCy). To improve the efficiency of GvHD prophylaxis in haploidentical peripheral blood stem cell transplantation combined with unrelated cord blood (Haplo-PBSCT-Cord), a novel regimen, which is composed of low dose of ATG (5 mg/kg) and low-dose PTCy (50 mg/kg) for GvHD prophylaxis, was evaluated in a prospective phase II clinical trial (Clinicaltrials.org NCT03395860). Thirty-two patients diagnosed with hematological malignancies were enrolled in this trial. All patients received myeloablative conditioning regimens except for three patients. The cumulative incidences (CIs) of grades II-IV and III-IV acute GvHD were 19.4% (95% CI, 5.5-33.3%) and 6.9% (95% CI, 0-16.3%) by day 100, respectively. The 1-year probability of relapse, disease free survival (DFS) and overall survival (OS) was 25.1% (95% CI, 7.3-42.9%), 59% (95% CI, 33.3-84.7%) and 78.4% (95% CI, 63-93.8%), respectively. The CIs of CMV and EBV reactivation by day 180 were 37.5% (95% CI, 19.8-55.2%) and 40.6% (95% CI, 22.6-58.6%), respectively. The results suggested that low-dose ATG with low-dose PTCy as GvHD prophylaxis in Haplo-PBSCT-Cord had promising activity.

Pitting Corrosion and Microstructure of J55 Carbon Steel Exposed to CO2/Crude Oil/Brine Solution under 2⁻15 MPa at 30⁻80 °C.

This study aimed to evaluate the corrosion properties of J55 carbon steel immersed in CO2/crude oil/brine mixtures present in the wellbores of CO2-flooded production wells. The main corroded position of wellbore was determined and wellbore corrosion law was provided. Corrosion tests were performed in 30% crude oil/brine solution under the simulated temperature (30⁻80 °C) and pressure (2⁻15 MPa) conditions of different well depths (0⁻1500 m). The corrosion behavior of J55 carbon steel was evaluated through weight-loss measurements and surface analytical techniques, including scanning electron microscopy, energy dispersive spectrometer, X-ray diffraction analysis, and optical digital microscopy. Corrosion rate initially increased and then decreased with increasing well depth, which reached the maximum value of 1050 m. At this well depth, pressure and temperature reached 11 MPa and 65 °C, respectively. Under these conditions, FeCO3 and CaCO3 localized on sample surfaces. Microscopy was performed to investigate corrosion depth distribution on the surfaces of the samples.

Effect of CO2 Partial Pressure on the Corrosion Behavior of J55 Carbon Steel in 30% Crude Oil/Brine Mixture.

The influence of CO2 partial pressure on the corrosion properties, including corrosion rate, morphology, chemical composition, and corrosion depth, of J55 carbon steel in 30% crude oil/brine at 65 °C was investigated. A corrosion mechanism was then proposed based on the understanding of the formation of localized corrosion. Results showed that localized corrosion occurred in 30% crude oil/brine with CO2. The corrosion rate sharply increased as the CO2 partial pressure (P co 2 ) was increased from 0 to 1.5 MPa, decreased from P co 2 = 1.5 MPa to P co 2 = 5.0 MPa, increased again at P co 2 = 5.0 MPa, and then reached a constant value after P co 2 = 9.0 MPa. The system pH initially decreased, rapidly increased, and then stabilized as CO2 partial pressure was increased. In the initial period, the surface of J55 carbon steel in the CO2/30% crude oil/brine mixtures showed intense corrosion. In conclusion, CO2 partial pressure affects the protection performance of FeCO3 by changing the formation of corrosion scale and further affecting the corrosion rate.

JAM3 maintains leukemia-initiating cell self-renewal through LRP5/AKT/ß-catenin/CCND1 signaling.

Leukemia-initiating cells (LICs) are responsible for the initiation, development, and relapse of leukemia. The identification of novel therapeutic LIC targets is critical to curing leukemia. In this report, we reveal that junctional adhesion molecule 3 (JAM3) is highly enriched in both mouse and human LICs. Leukemogenesis is almost completely abrogated upon Jam3 deletion during serial transplantations in an MLL-AF9-induced murine acute myeloid leukemia model. In contrast, Jam3 deletion does not affect the functions of mouse hematopoietic stem cells. Moreover, knockdown of JAM3 leads to a dramatic decrease in the proliferation of both human leukemia cell lines and primary LICs. JAM3 directly associates with LRP5 to activate the downstream PDK1/AKT pathway, followed by the downregulation of GSK3ß and activation of ß-catenin/CCND1 signaling, to maintain the self-renewal ability and cell cycle entry of LICs. Thus, JAM3 may serve as a functional LIC marker and play an important role in the maintenance of LIC stemness through unexpected LRP5/PDK1/AKT/GSK3ß/ß-catenin/CCND1 signaling pathways but not via its canonical role in cell junctions and migration. JAM3 may be an ideal therapeutic target for the eradication of LICs without influencing normal hematopoiesis.

Early tapering of immunosuppressive agents after HLA-matched donor transplantation can improve the survival of patients with advanced acute myeloid leukemia.

Disease recurrence is the most important obstacle to achieve long-term survival for patients with advanced acute myeloid leukemia (AML) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). In order to reduce the relapse risk and improve the survival, the strategy of early tapering of immunosuppressive agents was prospectively evaluated. Thirty-one patients with advanced AML received early tapering of immunosuppressive drugs, while 32 patients with AML in complete remission (CR) were given the routine tapering of immunosuppressive agents after HLA-matched donor transplantation. All advanced AML patients achieved CR after allo-HSCT. At 24 months after transplantation, relapse incidences were 22% in advanced group and 16% in CR group (P = 0.553); disease-free survival (DFS) and overall survival (OS) were 57.7 and 57.8% in advanced group, while in CR group were 66.6% (P = 0.388) and 66.2% (P = 0.423); immunosuppressive agent-free DFS (IDFS) were similar between two groups (P = 0.407). Acute graft-versus-host disease (aGvHD) incidences were similar between two groups (P = 0.311). Chronic GvHD (cGvHD) incidence was much higher in advanced group than in CR group (70.4 vs 38.7%, P = 0.02), but severe cGvHD had no difference. In multivariate analysis, cGvHD was an independent prognostic factor for lower risk of relapse and better DFS and OS; early tapering of immunosuppressive agents was an independent prognostic factor for cGvHD. The study suggested that advanced AML patients could be directly treated with allo-HSCT and its survival could be improved through the strategy of early tapering of immunosuppressive agents without significant adverse effects ( Clinicaltrials.org NCT03150134).

Involvement of miR-125a in resistance to daunorubicin by inhibiting apoptosis in leukemia cell lines.

In this study, we investigated whether miR-125a participated in the resistance of the leukemia cell lines to the chemotherapeutic agent daunorubicin. Higher expression of miR-125a is correlated with lower treatment response and shorter overall survival in acute leukemia patients. Overexpression of miR-125a induced drug resistance in HL-60, K562, and THP-1cell lines through reducing apoptosis. We also showed that miR-125a mediated daunorubicin resistance in leukemia cell lines through the decrease of GRK2 and Puma which were proved to be direct targets of miR-125a. This study may provide novel therapeutic targets for therapy and improve predictions of therapeutic responses in leukemia to daunorubicin.