A Novel Splicing Mutation Leading to Wiskott-Aldrich Syndrome from a Family.

Wiskott-Aldrich syndrome (WAS) is a rare X-linked recessive genetic disease characterized by clinical symptoms such as eczema, thrombocytopenia with small platelets, immune deficiency, prone to autoimmune diseases, and malignant tumors. This disease is caused by mutations of the WAS gene encoding WASprotein (WASP). The locus and type of mutations of the WAS gene and the expression quantity of WASP were strongly correlated with the clinical manifestations of patients. We found a novel mutation in the WAS gene (c.931 + 5G > C), which affected splicing to produce three abnormal mRNA, resulting in an abnormally truncated WASP. This mutation led to a reduction but not the elimination of the normal WASP population, resulting in causes X-linked thrombocytopenia (XLT) with mild clinical manifestations. Our findings revealed the pathogenic mechanism of this mutation.

Synergistic effect and molecular mechanism of PVA and UM171 in ex vivo expansion of primitive hematopoietic stem cells.

Umbilical cord blood (UCB) is a valuable source of hematopoietic stem cells (HSCs) used for transplantation; the number of cells in a single UCB is too small to quickly establish bone marrow (BM) implantation, and ex vivo expansion of HSCs has the potential to overcome this limitation. The purpose of this study is to explore the culture conditions conducive to the maintenance and expansion of hematopoietic stem and progenitor cells (HSPCs) and long-term hematopoietic stem cells (LT-HSCs) derived from human umbilical cord blood, compare the different effects of albumin (HSA) and polyvinyl alcohol (PVA), optimize the culture system using UM171 and investigate the molecular mechanism of PVA and UM171 promoting the expansion of primitive hematopoietic stem cells. CD34+ cells were purified from UCB using MacsCD34 beads, and then cultured in serum-free medium supplemented with cytokines for 12 days, with PVA or UM171 added according to experimental requirements; the relative percentage of different HSCs subsets after culture were detected by flow cytometry; CFU Assay Setup for detecting the multilineage differentiation potential of HSCs; RT-PCR detection of gene expression levels; reactive oxygen detection assessment of intracellular ROS levels. (1) The conditions of 20 ng/mlSCF, 100 ng/mlTPO, and 5% oxygen concentration are conducive to the maintenance of LT-HSCs. (2) Compared with HSA, PVA significantly increased the proportion of HSPCs and LT-HSCs, as well as dramatically promoted the expression of antioxidant enzymes and reduced the production of reactive oxygen species (ROS). (3) After adding UM171 to PVA-based medium, the proportion of HSPCs and LT-HSCs further increased, and downstream genes of Notch and Wnt pathways were selectively activated. (1) PVA may inhibit ROS production by upregulating the expression of antioxidant enzymes, which is beneficial for maintaining stemness and inhibiting differentiation of HSCs. (2) The antioxidant properties of PVA can delay differentiation, while UM171 can promote self-renewal by regulating the stem cell pathway, and the combination of them is beneficial for the maintenance and expansion of HSCs in vitro.

MEK/ERK and PI3K/AKT pathway inhibitors affect the transformation of myelodysplastic syndrome into acute myeloid leukemia via H3K27me3 methylases and de­methylases.

The transformation of myelodysplastic syndrome (MDS) into acute myeloid leukemia (AML) poses a significant clinical challenge. The trimethylation of H3 on lysine 27 (H3K27me3) methylase and de­methylase pathway is involved in the regulation of MDS progression. The present study investigated the functional mechanisms of the MEK/ERK and PI3K/AKT pathways in the MDS­to­AML transformation. MDS­AML mouse and SKM­1 cell models were first established and this was followed by treatment with the MEK/ERK pathway inhibitor, U0126, the PI3K/AKT pathway inhibitor, Ly294002, or their combination. H3K27me3 methylase, enhancer of zeste homolog (EZH)1, EZH2, demethylase Jumonji domain­containing protein­3 (JMJD3) and ubiquitously transcribed tetratricopeptide repeat on chromosome X (UTX) and H3K27me3 protein levels were determined using western blot analysis. Cell viability, cycle distribution and proliferation were assessed using CCK­8, flow cytometry, EdU and colony formation assays. The ERK and AKT phosphorylation levels in clinical samples and established models were determined, and SKM­1 cell behaviors were assessed. The levels of H3K27me3 methylases and de­methylases and distal­less homeobox 5 (DLX5) were measured. The results revealed that the ERK and AKT phosphorylation levels were elevated in patients with MDS and MDS­AML, and in mouse models. Treatment with U0126, a MEK/ERK pathway inhibitor, and Ly294002, a PI3K/AKT pathway inhibitor, effectively suppressed ERK and AKT phosphorylation in mice with MDS­AML. It was observed that mice with MDS treated with U0126/Ly294002 exhibited reduced transformation to AML, delayed disease transformation and increased survival rates. Treatment of the SKM­1 cells with U0126/Ly294002 led to a decrease in cell viability and proliferation, and to an increase in cell cycle arrest by suppressing ERK/PI3K phosphorylation. Moreover, treatment with U0126/Ly294002 downregulated EZH2/EZH1 expression, and upregulated JMJD3/UTX expression. The effects of U0126/Ly294002 were nullified when EZH2/EZH1 was overexpressed or when JMJD3/UTX was inhibited in the SKM­1 cells. Treatment with U0126/Ly294002 also resulted in a decreased H3K27me3 protein level and H3K27me3 level in the DLX5 promoter region, leading to an increased DLX5 expression. Overall, the findings of the present study suggest that U0126/Ly294002 participates in MDS­AML transformation by modulating the levels of H3K27me3 methylases and de­methylases, and regulating DLX5 transcription and expression.

[Clinical Efficacy and Survival Analysis of Adult Patients with Acute Myeloid Leukemia after Microtransplantation].

OBJECTIVE: To investigate the clinical efficacy and survival factors of microtransplantation (MST) in adult patients with acute myeloid leukemia (AML). METHODS: For a retrospective analysis of 27 adult patients with AML receiving MST from July 2014 to October 2021, the median age was 59(29-77) years old, 13 cases were ≥60 years old, 14 case were <60 years old, 13 cases were male and 14 cases were female. Classification by FAB: AML-M2 6 cases, AML-M4 6 cases, AML-M5 2 cases, AML-M6 2 cases, AML（Undivided type） 9 cases, AML myeloid sarcoma 2 cases (primary AML 21 cases, AML secondary to MDS 6 cases). Cytogenetic analysis showed 25 patients with a normal karyotype, 2 patients with an abnormal karyotype, and 20 patients with an abnormal molecular biology. Induction chemotherapy regimens mainly include: IA, DA, MA or HA regimen, including CAG or CIG in combination with decitabine, and single-agent decitabine. 17 patients achieved complete remission (CR) after 1 course of induction chemotherapy and 4 patients achieved CR after 2 courses of induction chemotherapy. 3 patients received CR by four courses of decitabine, 2 patients received no remission, and 1 patient underwent no induction chemotherapy and were treated direct MST. There were 16 patients with pretransplant CR and 11 patients were not in remission before transplantation. Follow-up mainly used consult patient's medical records and telephone inquiry to observe the adverse effects and efficacy of MST treatment. Survival analysis was performed by Kaplan-Meier method, with the main observation indicators overall survival(OS) and leukemia-free survival(LFS), and performed with the Log-rank test. Multivariate analysis was performed by the Cox regression model. RESULTS: A total of 79 MST were performed in 27 AML patients with good overall safety and no special serious adverse effects. The median time of leukocyte recovery was 13(4-28) days, and the median time of platelet recovery was 13(4-30) days. There were 50 cases of infection, 5 cases of abnormal liver function and 3 cases of abnormal cardiac function. Except for abnormal cardiac function, all other complications did not affect the treatment and were cure. Acute or chronic GVHD, renal insufficiency, abnormal coagulation function, and severe bleeding were not observed during treatment or during follow-up. As of the follow-up date, the median follow-up time of the 27 patients was 79(14-171) months, the median OS time was 62(1-171) months, and the median LFS time was 15(0-171) months. The 2-year OS rate was 65.7%（17/27）, and the 2-year LFS rate was 47.4%（12/27） . The complete response rate of 27 patients treated with MST was 48.1% (13/27). 8 patients relapsed during MST treatment, including 7 patients after the completion of the first MST course and 1 patient after the completion of the second MST course. 2 patients relapsed after the end of the course of MST. 13 patients died, including 10 patients because of disease progression, two patients from severe infection, and one patient from cardiac damage. CONCLUSION: MST has the advantages of small toxic side effects, complete compatibility of HLA matching is not required, effective avoidance of GVHD and rapid hematopoietic recovery, which can improve OS and LFS in elderly AML and young AML patients, and is one of the treatment options for patients without HLA matching.

TiO2 Gas Sensors Combining Experimental and DFT Calculations: A Review.

Gas sensors play an irreplaceable role in industry and life. Different types of gas sensors, including metal-oxide sensors, are developed for different scenarios. Titanium dioxide is widely used in dyes, photocatalysis, and other fields by virtue of its nontoxic and nonhazardous properties, and excellent performance. Additionally, researchers are continuously exploring applications in other fields, such as gas sensors and batteries. The preparation methods include deposition, magnetron sputtering, and electrostatic spinning. As researchers continue to study sensors with the help of modern computers, microcosm simulations have been implemented, opening up new possibilities for research. The combination of simulation and calculation will help us to better grasp the reaction mechanisms, improve the design of gas sensor materials, and better respond to different gas environments. In this paper, the experimental and computational aspects of TiO2 are reviewed, and the future research directions are described.

Synthesis of MoS2-based nanostructures and their applications in rechargeable ion batteries, catalysts and gas sensors: a review.

Molybdenum disulfide (MoS2) is a two-dimensional (2D) layered material with a graphene-like structure that has attracted attention because of its large specific surface area and abundant active sites. In addition, the compounding of MoS2 with other materials can enhance the performance in applications such as batteries, catalysts, and optoelectronic devices, etc. MoS2 is prepared by various methods, among which chemical deposition and hydrothermal methods are widely used. In this review, we focus on summarizing the applications of MoS2 and MoS2 composite nanomaterials in rechargeable ion batteries, catalysts for water splitting and gas sensors, and briefly outline the preparation methods.

EZH2/EHMT2 Histone Methyltransferases Inhibit the Transcription of DLX5 and Promote the Transformation of Myelodysplastic Syndrome to Acute Myeloid Leukemia.

Myelodysplastic syndrome (MDS) is characterized by clonal hematopoiesis and impaired differentiation, and may develop to acute myeloid leukemia (AML). We explored the mechanism of histone methyltransferase EZH2/EHMT2 during the transformation of MDS into AML. Expression of EZH2/EHMT2 in patients and NHD13 mice was detected. EZH2 and EHMT2 were silenced or overexpressed in SKM-1 cells. The cell proliferation and cycle were evaluated. Levels of DLX5, H3K27me3, and H3K9me2 in SKM-1 cells were detected. Binding of DLX5 promoter region to H3K27me3 and H3K9me2 was examined. Levels of H3K27me3/H3K9me2 were decreased by EZH2/EHMT2 inhibitor (EPZ-6438/BIX-01294), and changes of DLX5 expression and cell proliferation were observed. EZH2 was poorly expressed in MDS patients but highly expressed in MDS-AML patients. EHMT2 was promoted in both MDS and MDS-AML patients. EZH2 expression was reduced and EHMT2 expression was promoted in NHD13 mice. NHD13 mice with overexpressing EZH2 or EHMT2 transformed into AML more quickly. Intervention of EZH2 or EHMT2 inhibited SKM-1 cell proliferation and promoted DLX5 expression. When silencing EZH1 and EZH2 in SKM-1 cells, the H3K27me3 level was decreased. EZH2 silencing repressed the proliferation of SKM-1 cells. Transcription level of DLX5 in SKM-1 cells was inhibited by H3K27me3 and H3K9me2. Enhanced DLX5 repressed SKM-1 cell proliferation. In conclusion, EZH2/EHMT2 catalyzed H3K27me3/H3K9me2 to inhibit the transcription of DLX5, thus promoting the transformation from MDS to AML.

[Quantitative Analysis on Immunophenotype of CD34+ Myeloid Precursor Cells in Myelodysplastic Syndrome and Its Correlation with Clinical Features].

OBJECTIVE: To investigate the quantitative expression of immunophenotype of CD34+ myeloid precursor cells in myelodysplastic syndrome (MDS) patients and its correlation with clinical characteristics, and understand the effect of quantitative expression of CD7 and CD117 on the prognosis of low-risk MDS patients. METHODS: Multi-parameter flow cytometry (FCM) was used to detect the proportion and mean fluorescence intensity (MFI) of each antigen of bone marrow CD34+ myeloid precursor cells in 79 MDS patients. The correlation between the expression level of each immune marker and clinical characteristics was compared. The effects of quantitative expressions of CD7 and CD117 on the overall survival rate of low-risk patients were explored. RESULTS: Bone marrow blast cell proportion (P<0.01), RBC level (P<0.01), and Hb level (P<0.05) of high-risk MDS patients were higher, while EPO level (P<0.05) was lower than those of low-risk patients. The proportion of CD34+ blast cells (P<0.01), the proportion of CD117 (P<0.05) and the MFI of CD7 (P<0.05) were higher in high-risk patients than those in low-risk patients, but the MFI of CD123 was lower (P<0.05). In high-risk MDS patients, CD15/CD34 (MFI) and CD19/CD34 (MFI) positively correlated with the proportion of total T cells (r=0.458; r=0.505), while CD19/CD34 (%) and CD19/CD34 (MFI) negatively correlated with WBC levels (r=-0.469; r=-0.503). In low-risk MDS patients, CD34+ (%) positively correlated with bone marrow erythrocyte proportion, PLT level and neutrophil level (r=0.426; r=0.486; r=0.495), but negatively correlated with LDH level (r=-0.421); WT1 expression level was positively correlated with CD10/CD34 (%), CD10/CD34 (MFI) and CD117/CD34 (MFI) (r=0.745; r=0.800; r=0.434), while negatively correlated with CD11b/CD34 (%)(r=-0.457); CD19/CD34 (%) and CD71/CD34 (MFI) negatively correlated with NK cell proportion (r=-0.786; r=-0.514); CD10/CD34 (%) positively correlated with Th/Ts, while CD7/CD34 (MFI) negatively correlated with the proportion of Th cells (r=0.738; r=-0.513); HLADR/CD34 (%) and HLADR/CD34 (MFI) negatively correlated with PLT level (r=-0.461; r=-0.445), while HLADR/CD34 (MFI) positively correlated with bone marrow NAP fraction (r=0.552). The quantitative expression of CD7 and CD117 had no significant effect on the overall survival rate of low-risk MDS patients. CONCLUSION: The immunophenotype of CD34+ myeloid precursor cell in different risk groups in MDS patients is related to clinical characteristics. Bone marrow cell morphology, clinical and laboratory features and immunophenotype will be of great significance to the diagnosis, clinical classification and prognosis evaluation of MDS patients.

Leonurine-Repressed miR-18a-5p/SOCS5/JAK2/STAT3 Axis Activity Disrupts CML malignancy.

Leonurine, an active natural alkaloid compound isolated from Herba leonuri, has been reported to exhibit promising anticancer activity in solid tumors. The aim of this study was to explore whether leonurine is able to inhibit chronic myeloid leukemia (CML) malignancy. Here, we found that leonurine dose dependently inhibited the proliferation, migration, colony formation and promoted apoptosis of CML cells. Furthermore, leonurine markedly reduced CML xenograft growth in vivo. Mechanically, leonurine upregulated SOCS5 expression, thus leading JAK2/STAT3 signaling suppression. Silencing of SOCS5 by its siRNA abrogated the effect of leonurine on CML cells, demonstrating that SOCS5 mediates the anti-leukemia effect of leonurine. Notably, we observed that miR-18a-5p was remarkably increased in CML cells. Treating CML cells with leonurine significantly decreased miR-18a-5p expression. Moreover, we found miR-18a-5p repressed SOCS5 by directly targeting its 3'-UTR. miR-18a-5p downregulation induced by leonurine reduced the biological activity of CML cells by relieving miR-18a-5p repression of SOCS5 expression. Taken together, leonurine exerts significant anti-leukemia efficacy in CML by regulating miR-18a-5p/SOCS5/JAK2/STAT3 axis.

[Effect of Signal Transduction Pathway Gene Mutations on the One- course Induced Remission Rate and Analysis of Clinical Characteristics in Patients with CBF-AML].

OBJECTIVE: To investigate the effect of other gene mutations outside the fusion gene on the first complete remission (CR1) induced by one course of induction chemotherapy in patients with core binding factor-associated acute myeloid leukemia (CBF-AML). METHODS: DNA was extracted from bone marrow or peripheral blood samples of newly diagnosed CBF-AML patients admitted to the Hematology Department of the Second Hospital of Shanxi Medical University from January 2015 to January 2019. Next-generation sequencing was used for detection of 34 kinds of hematologic malignancy-related gene mutations in patients with CBF-AML, the effect of related gene mutations on the first complete remission (CR1) rate in one course of induction chemotherapy was analyzed by combineation with clinical characteristics. RESULTS: 34 kinds of genes in bone marrow or peripheral blood of 43 patients were detected by high throughput sequencing and the gene mutations were detected in 16 out of 34 genes. The mutation rate of KIT gene was the highest (48.8%), followed by NRAS (16.3%), ASXL1 (16.3%), TET2 (11.6%), CSF3R (9.3%), FLT3 (9.3%), KRAS (7.0%). The detection rates of mutations in different functional genes were as follows: genes related with signal transduction pathway (KIT, FLT3, CSF3R, KRAS, NRAS, JAK2, CALR, SH2B3, CBL) had the highest mutation frequency (72.1% (31/43); epigenetic modification gene mutation frequency was 30.2% (13/43), including ASXL1, TET2, BCOR); transcriptional regulation gene mutation frequency was 7.0% (3/43), including ETV6, RUNX1, GATA2). Splicing factor related gene mutation frequency was 2.3% (1/43), including ZRSR2). The CR1 rate was 74.4% after one course of induction chemotherapy. At first diagnosis, patients with low expression of WT1 (the median value of WT1 was 788.9) were more likely to get CR1 (P=0.032) and the RFS of patients who got CR1 after one course of induction chemotherapy was significantly longer than that of patients without CR1 [7.6 (2.2-44.1) versus 5.8 (1-19.4), (P=0.048)]. The rate of CR1 in the signal transduction pathway gene mutation group was significantly lower than that in non-mutation group (64.5% vs 100%) (P=0.045), while the level of serum hydroxybutyrate dehydrogenase (HBDH) was significantly higher than that in non-mutation group [(418 (154-2702) vs 246 (110-1068)] (P=0.032). There was no difference in CD56 expression between the two groups (P=0.053), which was limited to the difference between (≥20%) expression and non-expression. (P=0.048). CONCLUSION: CBF-AML patients with signal transduction pathway gene mutation are often accompanied by high HBDH level and CD56 expression, moreover, the remission rate induced by one course of treatment is low.

Disulfiram/cytarabine eradicates a subset of acute myeloid leukemia stem cells with high aldehyde dehydrogenase expression.

Most patients with acute myeloid leukemia (AML) achieve complete remission (CR) after induction chemotherapy, however, in some patients, the disease subsequently relapses and may lead to death. Leukemia stem cells (LSC) have been identified as the main cause for recurrence. Increased aldehyde dehydrogenase (ALDHhigh) activity in a variety of cancer stem cells prevents effective action of chemotherapeutic drugs. In this study, we found that approximately 50.7% of AML patients had ALDHhigh, and the presence of ALDHhigh stem cells was associated with poor cytogenetic prognosis. Lentiviral vector transduced ALDHhigh leukemia cell lines are insensitive to the conventional chemotherapy drug cytarabine, and inhibition of ALDH activity by disulfiram (DSF) can increase the sensitivity of ALDHhigh leukemia cells to cytarabine. Unlike traditional chemotherapy drugs, DSF is not toxic to healthy umbilical cord blood stem cells. An ALDHhigh leukemia cell xenograft model was established using immunodeficient mice to mimic the disease environment, and DSF and cytarabine were found to eliminate the ALDHhigh leukemia cells in transplanted mice while not affecting the healthy blood cells of mice. These findings suggest that DSF may have therapeutic potential by inhibiting ALDH activity and thereby increasing chemosensitivity.

Clinical features and prognosis of normal karyotype acute myeloid leukemia pediatric patients with WT1 mutations: an analysis based on TCGA database.

Objectives: To explore the clinical features and prognosis of normal karyotype acute myeloid leukemia (NK-AML) pediatric patients with WT1 mutations.Methods: The clinical data and prognostic information of 220 NK-AML pediatric patients were selected from target-AML project of The Cancer Genome Atlas (TCGA) database. Survival analyses were performed for NK-AML pediatric patients with different combinations of mutations.Results: We found that 28(12.7%) NK-AML patients harbored WT1 mutations. The positive rate of FLT3-ITD in the WT1-mutated group was higher than that in the WT1 wild-type group (P = 0.002). In contrast, WT1 mutation and NPM1 mutation were mutually exclusive (P = 0.013). Furthermore, the WT1-mutated group suffered lower rates of complete remission (CR) (P < 0.001 and P < 0.001, respectively) but higher rates of minimal residual disease (MRD) (P = 0.003 and P = 0.021, respectively) after both one and two courses of induction chemotherapy. Patients with WT1 mutations had significantly worse overall survival (OS) and event-free survival (EFS) in both univariate (P < 0.001 and P = 0.007, respectively) and multivariate survival analyses (P < 0.001 and P < 0.001, respectively). The stratification analysis showed that for FLT3-ITD positive patients, WT1 mutations predicted shorter OS (P = 0.003) and EFS (P < 0.001).Conclusion: WT1 mutations conferred an independent poor prognosis for NK-AML pediatric patients.

Two activating mutations of MPL in triple-negative myeloproliferative neoplasms.

MPLW515K or W515L mutation plays an important role in the pathogenesis of myeloproliferative neoplasms (MPNs) through signaling molecules of the cytokine receptor axis. Besides MPLW515K or W515L, more than 30 atypical MPL mutations have been reported in patients who are negative for JAK2V617F, MPLW515K/L, and CALR mutations. Here, we aimed to identify the disease-causing mutations in the triple-negative case of ET. We described two MPL mutations in patients diagnosed with ET by target sequencing the hotspot mutation region of MPL gene. The MPLA497-L498ins4 is an insertion mutation detected recurrently in ET patients, and the MPLW515RQ516E is a novel double-point mutation found in an ET patient. Functional studies of MPLA497-L498ins4 and MPLW515RQ516E revealed that they are gain-of-function mutations. Mutants of MPLA497-L498ins4 and MPLW515RQ516E promoted autonomous proliferation on Ba/F3 cells in the absence of IL-3. Autonomous activation of TPO-R without ligand TPO was observed in MPLA497-L498ins4 and MPLW515RQ516E mutants. Lower percentage of cells in G1 phase and higher percentage of cells in S phase of two atypical MPL mutants were detected after culturing without any cytokines. These two atypical MPL mutations also presented increase in phosphorylation of signaling proteins including JAK2/STAT, PI3K/AKT, and MAPK/RAS. In summary, the MPLA497-L498ins4 and MPLW515RQ516E are gain-of-function mutations which may be novel driving factors participating in the pathogenesis of triple-negative MPN.

[Clinical Efficacy of Modified BU/CY as Conditioning Regimen Combined with Autologous Peripheral Blood Hematopoietic Stem Cell Transplantation in Young Acute Myeloid Leukemia Patients with Low or Intermediate Risk].

OBJECTIVE: To investigate the safety and efficacy of autologous peripheral blood hematopoietic stem cell transplantation (auto-PBHSCT) using modified BU/CY conditioning regimen for young AML patients of low and middle risk in the first complete remission (CR1). METHODS: Ten young AML patients of low and middle risk who did not want to accept allogeneic hematopoietic stem cell transplantation（allo-HSCT）and underwent auto-PBHSCT in CR1 during May 2013 to December 2016 were retrospectively analyzed. From 3 months after auto-PBHSCT, the maintenance therapy with interleukin-2 (IL-2) or IL-2 combined with histamine dihydrochloride was performed for these patients in the next 18 months. The side effects of the conditioning regimen, hematopoietic recovery time, transplant-related mortality (TRM) within 100 days and 1 year after auto-PBHSCT, relapse rate, leukemia-free survival (LFS) rate at 2 years and 3 years, overall survival (OS) were evaluated at 3 years and 4 years. RESULTS: Gastrointestinal side effects were the major non-hematologic toxicity reaction, among which, 7 cases relatively mild and 3 cases displayed moderate, just one case suffered from severe reaction. In 4 cases, the mild liver damage occurred, but no hemorrhagic cystitis occurred. All the patients experienced different kinds of infection, including 5 cases of bloodstream infection, 2 cases of gastrointestinal infection, 3 cases of crissum infection and 2 cases of oral infection. The myeloablative effect occurred in all ten patients. The median times for absolute neutrophil count (ANC)<0.5×109/L and for platelet count <20.0×109/L were 1.5 (0-3) days and 3 (2-5) days after transplantation, respectively. The patients achieved ANC>0.5×109/L at 10 to 19 days, median was 13 days after auto-PBHSCT. The patients achieved platelet count >20×109/L at 10 to 72 days; median was 32 days after auto-PBHSCT. The TRM within 100 days and 1 year after transplantation was 0. The relapse occurred in 2 cases at 6 and 14 months after auto-PBHSCT raspectively. The median follow-up time was 48.1 months, and the median survival time was 54.7 months after transplantation. The 2-year and 3-year LFS were 100% (10 cases) and 80% (8 cases), respectively. The 3-year and 4-year OS were 80% (8 cases) and 70% (7 cases), respectively. CONCLUSION: Modified BU/CY as conditioning regimen for auto-PBHSCT can achieve the myeloablative effect without raising TRM and obtain good LFS and OS. As for young AML patients without high risk, it is a valuable therapeutic option, especially for those lacking the chance of allo-HSCT.

TET2 rs2454206, TET2 rs12498609 and ASXL1 rs3746609 single nucleotide polymorphisms in patients with myelodysplastic syndromes.

To study the association between TET2rs2454206, TET2rs12498609 and ASXL1rs3746609 and Myelodysplastic syndromes (MDS), a total of 90 MDS patients and 143 healthy volunteers were included. The clinical data, bone marrow samples of patients and peripheral blood samples of volunteers were obtained. We found TET2rs2454206 G/A genotype, TET2rs12498609 G/C genotype and ASXL1rs3746609 A/G genotype in 13.3%, 11.1%, 10.1% MDS patients and in 42.7%, 22.4%, 23.8% healthy volunteers (P < 0.001; P = 0.029; P = 0.009, respectively). TET2 rs2454206 G/A genotype was associated with higher serum LDH level in MDS (P = 0.025). Patients with TET2rs12498609 G/C genotype were characterized with higher frequency of mutated SRSF2 gene (P = 0.042) and lower occurrence rate of anemia (P = 0.026) than those with C/C genotype. ASXL1rs3746609 A/G genotype linked with higher thrombocyte counts (P = 0.02) and percent of total T lymphocyte (P = 0.029), whereas with lower percent of NK cell (P = 0.032) and B lymphocyte (P = 0.007). None of these three SNPs had impact on the overall survival and disease progression to AML. We concluded that People with TET rs2454206 G/A genotype, TET2rs12498609 G/C genotype or ASXL1rs3746609 A/G genotype were related to lower prevalence of MDS. All of the three SNPs were associated with certain laboratory features in MDS patients.

The CD9+ CD11b- HLA-DR- immunophenotype can be used to diagnose acute promyelocytic leukemia.

OBJECTIVE: To investigate the immunophenotypic characteristics of acute promyelocytic leukemia (APL) and explore the sensitivity and specificity of various antibody combinations for the timely and accurate diagnosis APL. METHODS: A retrospective analysis was performed using morphological, immunological, genetic, and molecular biological data from 92 patients diagnosed with APL and 190 controls diagnosed with non-APL acute myeloid leukemia. RESULTS: For APL diagnosis, the CD9/CD11b/human leukocyte antigen (HLA)-DR antibody combination had 85% sensitivity and 95% specificity, AUC = 0.85. However, the sensitivity and specificity were 39% and 92%, AUC = 0.65, respectively, for the HLA-DR/CD34/CD117 combination, and 80% and 80%, AUC = 0.80, respectively for the CD11b/HLA-DR combination. Significant differences were observed between the different antibody combinations. CONCLUSIONS: The CD9/CD11b/HLA-DR antibody combination displays high sensitivity and specificity and can be used to diagnose APL.

Droplet digital PCR for BCR/ABL(P210) detection of chronic myeloid leukemia: A high sensitive method of the minimal residual disease and disease progression.

OBJECTIVE: This study intended to establish a droplet digital PCR (dd-PCR) for monitoring minimal residual disease (MRD) in patients with BCR/ABL (P210)-positive chronic myeloid leukemia (CML), thereby achieving deep-level monitoring of tumor load and determining the efficacy for guided clinically individualized treatment. METHODS: Using dd-PCR and RT-qPCR, two cell suspensions were obtained from K562 cells and normal peripheral blood mononuclear cells by gradient dilution and were measured at the cellular level. At peripheral blood (PB) level, 61 cases with CML-chronic phase (CML-CP) were obtained after tyrosine kinase inhibitor (TKI) treatment and regular follow-ups. By RT-qPCR, BCR/ABL (P210) fusion gene was undetectable in PB after three successive analyses, which were performed once every 3 months. At the same time, dd-PCR was performed simultaneously with the last equal amount of cDNA. Ten CML patients with MR4.5 were followed up by the two methods. RESULTS: At the cellular level, consistency of results of dd-PCR and RT-qPCR reached R2  ≥ 0.99, with conversion equation of Y = 33.148X1.222 (Y: dd-PCR results; X: RT-qPCR results). In the dd-PCR test, 11 of the 61 patients with CML (18.03%) tested positive and showed statistically significant difference (P < .01). In the follow-up of 10 CML patients who were in MR4.5. All patients were loss of MR4.0, and 4 were tested positive by dd-PCR 3 months earlier than by RT-qPCR. CONCLUSION: In contrast with RT-qPCR, dd-PCR is more sensitive, thus enabling accurate conversion of dd-PCR results into internationally standard RT-qPCR results by conversion equation, to achieve a deeper molecular biology-based stratification of BCR/ABL(P210) MRD. It has some reference value to monitor disease progression in clinic.