Identification of cell surface markers for acute myeloid leukemia prognosis based on multi-model analysis

Given the extremely high inter-patient heterogeneity of acute myeloid leukemia(AML),the identification of biomarkers for prognostic assessment and therapeutic guidance is critical.Cell surface markers(CSMs)have been shown to play an important role in AML leukemogenesis and progression.In the current study,we evaluated the prognostic potential of all human CSMs in 130 AML patients from The Cancer Genome Atlas(TCGA)based on differential gene expression analysis and univariable Cox proportional hazards regression analysis.By using multi-model analysis,including Adaptive LASSO regression,LASSO regression,and Elastic Net,we constructed a 9-CSMs prognostic model for risk stratification of the AML patients.The predictive value of the 9-CSMs risk score was further validated at the transcriptome and proteome levels.Multivariable Cox regression analysis showed that the risk score was an independent prognostic factor for the AML patients.The AML patients with high 9-CSMs risk scores had a shorter overall and event-free survival time than those with low scores.Notably,single-cell RNA-sequencing analysis indicated that patients with high 9-CSMs risk scores exhibited chemotherapy resistance.Furthermore,PI3K inhibitors were identified as potential treatments for these high-risk patients.In conclusion,we constructed a 9-CSMs prognostic model that served as an independent prognostic factor for the survival of AML patients and held the potential for guiding drug therapy.

Synergistic Effects of Glutamine Deprivation and Metformin in Acute Myeloid Leukemia

Objective The metabolic reprogramming of acute myeloid leukemia(AML)cells is a compensatory adaptation to meet energy requirements for rapid proliferation.This study aimed to examine the synergistic effects of glutamine deprivation and metformin exposure on AML cells.Methods SKM-1 cells(an AML cell line)were subjected to glutamine deprivation and/or treatment with metformin or bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl)ethyl sulfide(BPTES,a glutaminase inhibitor)or cytarabine.Cell viability was detected by Cell Counting Kit-8(CCK-8)assay,and cell apoptosis and reactive oxygen species(ROS)by flow cytometry.Western blotting was conducted to examine the levels of apoptotic proteins,including cleaved caspase-3 and poly(ADP-ribose)polymerase(PARP).Moreover,the human long noncoding RNA(lncRNA)microarray was used to analyze gene expression after glutamine deprivation,and results were confirmed with quantitative RT-PCR(qRT-PCR).The expression of metallothionein 2A(MT2A)was suppressed using siRNA.Cell growth and apoptosis were further detected by CCK-8 assay and flow cytometry,respectively,in cells with MT2A knockdown.Results Glutamine deprivation or treatment with BPTES inhibited cell growth and induced apoptosis in SKM-1 cells.The lncRNA microarray result showed that the expression of MT family genes was significantly upregulated after glutamine deprivation.MT2A knockdown increased apoptosis,while proliferation was not affected in SKM-1 cells.In addition,metformin inhibited cell growth and induced apoptosis in SKM-1 cells.Both glutamine deprivation and metformin enhanced the sensitivity of SKM-1 cells to cytarabine.Furthermore,the combination of glutamine deprivation with metformin exhibited synergistic antileukemia effects on SKM-1 cells.Conclusion Targeting glutamine metabolism in combination with metformin is a promising new therapeutic strategy for AML.

Adult rhabdomyosarcoma combined with acute myeloid leukemia: A case report

BACKGROUND Rhabdomyosarcoma is a tumor of mesenchymal origin.Secondary leukemia is a complication of previous transformation to other hematologic disorders or is a treatment-related acute myeloid leukemia secondary to cytotoxic chemotherapy or radiation therapy for other malignancies.CASE SUMMARY We present the case of a 36-year-old female patient who was diagnosed with rhabdomyosarcoma and acute myeloid leukemia.Further disease progression was observed after multiline chemotherapy.Eventually,the patient suffered cerebral hemorrhage,which resulted in death.CONCLUSION The incidence of rhabdomyosarcoma in adults is extremely low,and secondary leukemia caused by rhabdomyosarcoma is even rarer.Secondary leukemia has a very poor prognosis and a low overall survival rate.

Circ_0012152 Accelerates Acute Myeloid Leukemia Progression through the miR-652-3p/SOX4 Axis

Objective Acute myeloid leukemia(AML)is an aggressive hematological malignancy characterized by abnormal myeloid blast expansion.Recent studies have demonstrated that circular RNAs play a role in AML pathogenesis.In this study,we aimed to investigate the clinical significance of circ_0012152 in AML and elucidate its underlying molecular mechanism in the pathogenesis of this condition.Methods Circ_0012152 expression was detected by quantitative real-time polymerase chain reaction in samples obtained from 247 patients with AML and 40 healthy controls.A systematic analysis of clinical characteristics and prognostic factors was also conducted.Cell growth was assessed using the Cell Counting Kit-8(CCK-8)assay,and apoptosis and cell cycle progression were evaluated by flow cytometry.Moreover,RNA pull-down was performed to identify target microRNAs,and transcriptome RNA sequencing and bioinformatics analyses were utilized to identify downstream mRNA targets.Results Circ_0012152 was significantly upregulated in samples from patients with AML and served as an independent adverse prognostic factor for overall survival(OS)(hazard ratio:2.357;95%confidence interval 1.258–4.415).The circ_0012152 knockdown reduced cell growth,increased apoptosis,and inhibited cell cycle progression in AML cell lines.RNA pull-down and sequencing identified miR-652-3p as a target microRNA of circ_0012152.Cell growth inhibition by circ_0012152 knockdown was significantly relieved by miR-652-3p inhibitors.We suggested that miR-652-3p targeted SOX4,as the decrease in SOX4 expression resulting from circ_0012152 knockdown was upregulated by miR-652-3p inhibitors in AML cells.Conclusion Circ_0012152 is an independent poor prognostic factor for OS in AML,and it promotes AML cell growth by upregulating SOX4 through miR-652-3p.

Quality-adjusted time without symptoms or toxicity analysis of haploidentical-related donor vs.identical sibling donor hematopoietic stem cell transplantation in acute myeloid leukemia

Objective:We aimed to compare the quality-adjusted time without symptoms or toxicity(Q-TWiST)in acute myeloid leukemia(AML)patients who received haploidentical-related donor(HID)and identical sibling donor(ISD)hematopoietic stem cell transplantation(HSCT).Methods:Five clinical health states were defined:toxicity(TOX),acute graft-versus-host disease(GVHD),chronic GVHD(cGVHD),time without symptoms and toxicity(TWiST)and relapse(REL).The equation used in this study was as follows:Q-TWiST=UTOX×TOX+UTWiST×TWiST+UREL×REL+UaGVHD×aGVHD+UcGVHD×cGVHD.Results:A total of 239 AML patients were enrolled.We established a mathematical model,i.e.,Q-TWiST HID HSCT>Q-TWiST ISD HSCT,to explore the range of utility coefficients satisfying the inequality.Based on the raw data,the utility coefficient is equivalent to the following inequality:10.57067UTOX-46.27733UREL+105.9374+3.388078UaGVHD-210.8198UcGVHD>0.The model showed that when UTOX,UREL,and UaGVHD were within the range of 0-1,as well as when UcGVHD was within the range of 0-0.569,the inequality Q-TWiST HID HSCT>Q-TWiST ISD HSCT was valid.According to the results of the ChiCTR1800016972 study,the median coefficients of TOX,acute GVHD(aGVHD),and cGVHD were 0.56(0.41-0.76),0.56(0.47-0.72),and 0.54(0.37-0.79),respectively.We selected a series of specific examples of the coefficients,i.e.,UTOX=0.5,UREL=0.05,UaGVHD-0.5,and UcGVHD-0.5.The Q-TWiST values of ISD and HID HSCT were 896 and 900 d,respectively(P=0.470).Conclusions:We first observed that Q-TWiST was comparable between AML patients receiving HID HSCT and those receiving ISD HSCT.

Transforming growth factor-β1 and vascular endothelial growth factor levels in senile acute myeloid leukemia and correlation with prognosis

BACKGROUND Acute myeloid leukemia(AML)is a disease in which immature hematopoietic cells accumulate in the bone marrow and continuously expand,inhibiting hematopoiesis.The treatment and prognosis of this disease have always been unsatisfactory.AIM To investigate the correlation between vascular endothelial growth factor(VEGF)and transforming growth factor-β1(TGFβ1)expression and prognosis in older adults with AML.METHODS This study enrolled 80 patients with AML(AML group),including 36 with complete response(AML-CR),23 with partial response(AML-PR),and 21 with no response(AML-NR).The expression levels of VEGF and TGFβ1 were detected by reverse transcription polymerase chain reaction in bone marrow mononuclear cells isolated from 56 healthy controls.Kaplan-Meier analysis was performed to assess overall survival(OS)and progression-or disease-free survival(DFS).Prognostic risk factors were analyzed using a Cox proportional hazards model.RESULTS The AML group showed a VEGF level of 2.68±0.16.VEGF expression was lower in patients with AML-CR than those with AML-PR or AML-NR(P<0.05).TGFβ1 expression in the AML group was 0.33±0.05.Patients with AML-CR showed a higher TGFβ1 expression than those with AML-PR or AML-NR(P<0.05).VEGF and TGFβ1 expression in patients with AML was significantly correlated with the counts of leukocytes,platelets,hemoglobin,and peripheral blood immature cells(P<0.05);Kaplan-Meier survival analysis revealed that patients with high TGFβ1 expression had better OS and DFS than those with low TGFβ1 expression(P<0.05),whereas patients with low VEGF levels showed better OS and DFS than those with high VEGF levels(P<0.05).VEGF,TGFβ1,and platelet count were identified by the Cox proportional hazards model as independent risk factors for OS(P<0.05),while VEGF,TGFβ1,and white blood cell count were independent risk factors for DFS(P<0.05).CONCLUSION Decreased VEGF expression and increased TGFβ1 expression in patients with AML provide valuable references for determining and individualizing clinical treatment strategies.

Network pharmacology to decipher the mechanism of Danggui Longhui Wan against chronic myeloid leukemia

Chronic myeloid leukemia(CML)is a hematopoietic myeloproliferative disorder.The Chinese prescription Danggui Longhui Wan(DGLHW)has been utilized in CML treatment,but its underlying mechanisms remain unclear.In this study,we gathered 794 constituents,1249 drug targets,1654 disease genes and 129 intersection genes.GO and KEGG were used to analyze the function of these genes.Compatibility of prescription study showed that monarch drug,minister drug,assistant and guide drug played a synergistic role in the treatment of CML.In addition,we obtained 20 hub genes and 12 key components.Molecular docking indicated that the main compounds and core proteins had good binding ability.The results of this study also showed that DGLHW might play a role in the treatment of CML by affecting MAPK,PI3K/AKT,FoxO and p53 signaling pathways.

Clinical Effects of Venetoclax in the Treatment of Acute Myeloid Leukemia in the Elderly

Objective: To investigate the clinical efficacy of venetoclax in the treatment of elderly acute myeloid leukemia (AML). Methods: 50 cases of elderly AML patients receiving venetoclax for treatment in the hospital from January 2022 to January 2024 were selected, including 38 cases of patients whose primary treatment was not suitable for intensive chemotherapy and 12 cases of relapsed/refractory AML patients, to observe the therapeutic efficacy and safety of venetoclax. Results: Among the 38 patients whose primary treatment was not suitable for intensive chemotherapy, 5 cases were treated with venetoclax monotherapy, 33 cases were treated with venetoclax + azacitidine, and 25 patients (65.79%) achieved complete remission (CR) with incomplete hematologic recovery (CRi) after 28 days of treatment;10 patients with relapsed/refractory AML were treated with venetoclax + azacitidine, and 2 patients were treated with venetoclax + azacitidine + chemotherapy, and 2 patients achieved optimal therapeutic response after 28 days of treatment and CR/CRi was achieved in 7 patients (58.33%). There were 47 (94.0%) patients with grade 3 or higher granulocytopenia, 46 (92.0%) patients with hemoglobin reduction, and 43 (86.0%) patients with thrombocytopenia, developed after 28 days of treatment. 11 patients developed infections after treatment and there was one case of tumor lysis syndrome. Conclusion: The response rate of venetoclax monotherapy and combination in elderly AML induction therapy is high, and the overall tolerability of elderly patients is good, so it can be popularized and applied.

Observation on the Clinical Effect of Applying Venetoclax Combined with Demethylation Drug Therapy in Patients with Acute Myeloid Leukemia

Objective: To investigate the therapeutic effect of applying venetoclax combined with demethylating drugs in treating patients with acute myeloid leukemia (AML). Methods: Eighty cases of AML patients treated with venetoclax combined with demethylating drugs in our hospital were selected from March 2021 to March 2024, including 40 cases of primary treatment patients and 40 cases of relapsed and refractory patients. The efficacy and safety of the combined drug therapy was analyzed. Results: The primary treatment group was presented with a complete remission (CR) rate of 40.5%, partial remission (PR) rate of 47.50%, no response (NR) rate of 12.50%, and a remission rate of 87.50%. The relapsed- refractory group was presented with a CR rate of 37.50%, PR rate of 42.50%, NR rate of 17.50%, and a remission rate of 87.50%. There was no statistical significance between the groups (P > 0.05). The hematological adverse reactions of the combined treatment for AML were leukopenia and the non-hematological adverse reactions were mainly infections, with an incidence rate of 87.50%. Conclusion: The efficacy of venetoclax combined with demethylating drugs in AML was remarkable and the treatment regimen can be adjusted according to the treatment-resistant response.

Bone marrow microRNA-34a is a good indicator for response to treatment in acute myeloid leukemia

Background:microRNA 34a(miR 34a)had been reported to have a diagnostic role in acute myeloid leukemia(AML).However,its value in the bone marrow(BM)of AML patients,in addition to its role in response to therapy is still unclear.The current study was designed to assess the diagnostic,prognostic,and predictive significance of miR 34a in the BM of AML patients.Methods:The miR.34a was assed in BM aspirate of 82 AML patients in relation to 12 normal control subjects using qRT-PCR.The data were assessed for correlation with the relevant dinical critenia,response to therapy,disease-free survival(DFS),and overall survival(OS)rates.Results:miR.34a was significantly downregulated in AML patients[0.005(3.3×10^(-6)-1.32)],compared to the control subjects[0.108(3.2× 10^(-4)-1.64),p=0.021].The.median relative quantification(RQ)of miR-34a was 0.106(range;0-32.12).The specifaity,sensitivity,and area under the curve(AUC)for the diagnosis of AML were(58.3%,69.5%,0.707,respectively,p=0.021).patients with upregulated miR-34a showed decreased platelets count<34.5 × 10^(9)/L,and achieved early complete remission(CR,p=0.031,p=0.044,respectively).Similarly,patients who were refractory to therapy showed decreased miR 34a levels in comparison to those who achieved CR[0.002(0-0.01)and 0.12(0-32.12),respectively,p=0.002].Therefore,miR 34a could significantly identify patients with CR with a specificity of 75%and sensitivity of 100%at a cut-off of 0.014(AUC=0.927,p=0.005).There was no considerable association between miR-34a expression and survival rates of the induded AML patients.Condusion:miR-34a could be a beneficial diagnostic biomarker for AML patients.In addition,it serves as a good indicator for response to therapy,which could possibly identify patients who are refractory to treatment with 100%sensitivity and 75%specificity.

Resveratrol-downregulated Phosphorylated Liver Kinase B1 Is Involved in Senescence of Acute Myeloid Leukemia Stem Cells

Summary： Senescence is an important obstacle to cancer development. Engaging a senescent response may be an effective way to cure acute myeloid leukemia （AML）. The aim of this study was to examine the effect of resveratrol-downregulated phosphorylated liver kinase B1 （pLKB1） on the senescence of acute myeloid leukemia （AML） stem cells. The protein expressions of pLKB 1 and Sirtuin 1 （SIRT1）, a regulator ofpLKB1, were measured in CD34＋CD38-KGla cells treated with resveratrol （40 μmol/L） or not by Western blotting. Senescence-related factors were examined, including p21 mRNA tested by real-time PCR, cell morphology by senescence-associated β-galactosidase （SA-β-gal） staining, cell pro- liferation by MTT assay and cell cycle by flow cytometry. Besides, apoptosis was flow cytometrically determined. The results showed that pLKB1 was highly expressed in CD34＋CD38- KGla cells, and resveratrol, which could downregulate pLKB1 through activation of SIRT1, induced senescence and apoptosis of CD34＋CD38- KGla cells. It was concluded that resveratrol-downregulated pLKB1 is in- volved in the senescence of AML stem cells.

Bone marrow niche-mediated survival of leukemia stem cells in acute myeloid leukemia: Yin and Yang

Acute myeloid leukemia （AML） is characterized by the accumulation of circulating immature blasts that exhibit uncontrolled growth, lack the ability to undergo normal differentiation, and have decreased sensitivity to apoptosis. Accumulating evidence shows the bone marrow （BM） niche is critical to the maintenance and retention of hematopoietic stem cells （HSC）, including leukemia stem cells （LSC）, and an increasing number of studies have demonstrated that crosstalk between LSC and the stromal cells associated with this niche greatly influences leukemia initiation, progression, and response to therapy. Undeniably, stromal cells in the BM niche provide a sanctuary in which LSC can acquire a drug-resistant phenotype and thereby evade chemotherapy- induced death. Yin and Yang, the ancient Chinese philosophical concept, vividly portrays the intricate and dynamic interactions between LSC and the BM niche. In fact, LSC-induced microenvironmental reprogramming contributes significantly to leukemogenesis. Thus, identifying the critical signaling pathways involved in these interactions will contribute to target optimization and combinatorial drug treatment strategies to overcome acquired drug resistance and prevent relapse following therapy. In this review, we describe some of the critical signaling pathways mediating BM niche-LSC interaction, including SDFI/CXCL12, Wnt/β-catenin, VCAM/VLA-4/NF-κB, CD44, and hypoxia as a newly-recognized physical determinant of resistance, and outline therapeutic strategies for overcoming these resistance factors.

Update on acute myeloid leukemia stem cells:New discoveries and therapeutic opportunities

The existence of cancer stem cells has been wellestablished in acute myeloid leukemia. Initial proof of the existence of leukemia stem cells(LSCs) was accomplished by functional studies in xenograft models making use of the key features shared with normal hematopoietic stem cells(HSCs) such as the capacity of self-renewal and the ability to initiate and sustain growth of progenitors in vivo. Significant progress has also been made in identifying the phenotype and signaling pathways specific for LSCs. Therapeutically, a multitude of drugs targeting LSCs are in different phases of preclinical and clinical development. This review focuses on recent discoveries which have advanced our understanding of LSC biology and provided rational targets for development of novel therapeutic agents. One of the major challenges is how to target the selfrenewal pathways of LSCs without affecting normal HSCs significantly therefore providing an acceptable therapeutic window. Important issues pertinent to the successful design and conduct of clinical trials evaluating drugs targeting LSCs will be discussed as well.

Chronic myeloid leukemia-from the Philadelphia chromosome to specific target drugs:A literature review

Chronic myeloid leukemia(CML)is a myeloproliferative neoplasm and was the first neoplastic disease associated with a well-defined genotypic anomaly―the presence of the Philadelphia chromosome.The advances in cytogenetic and molecular assays are of great importance to the diagnosis,prognosis,treatment,and monitoring of CML.The discovery of the breakpoint cluster region(BCR)-Abelson murine leukemia(ABL)1 fusion oncogene has revolutionized the treatment of CML patients by allowing the development of targeted drugs that inhibit the tyrosine kinase activity of the BCR-ABL oncoprotein.Tyrosine kinase inhibitors(known as TKIs)are the standard therapy for CML and greatly increase the survival rates,despite adverse effects and the odds of residual disease after discontinuation of treatment.As therapeutic alternatives,the subsequent TKIs lead to faster and deeper molecular remissions;however,with the emergence of resistance to these drugs,immunotherapy appears as an alternative,which may have a cure potential in these patients.Against this background,this article aims at providing an overview on CML clinical management and a summary on the main targeted drugs available in that context.

Synchronous diagnosis and treatment of acute myeloid leukemia and chronic lymphocytic leukemia:Two case reports

BACKGROUND The concurrence of acute myeloid leukemia(AML)and chronic lymphocytic leukemia(CLL)is rare.Previous reports of such cases have focused mainly on clinical diagnosis and characteristics,so the mechanism remains unclear,and therapy options have been poorly explored.CASE SUMMARY Here,we report two cases of synchronous AML and CLL.Flow cytometry revealed two distinct abnormal cell populations(myeloblasts and lymphoid cells)according to scatter characteristics.CD5-positive B cell lymphoma with myeloid leukemia invasion was observed on lymph node biopsy.Chemotherapy regimens indicated for both AML and CLL were used in our patients,and our patients achieved complete response after chemotherapy.Next-generation sequencing of 88 genes was performed.CONCLUSION We conclude that early mutation and dysregulation at the hematopoietic stem cell stage and the accumulation of multiple rearrangements may cause the concurrence of CLL and AML.The treatment of infection and combination therapy aimed at the CLL component are significant in the management of patients with concurrent CLL and AML.

Pediatric acute myeloid leukemia patients with i(17)(q10)mimicking acute promyelocytic leukemia:Two case reports

BACKGROUND Chromosome i(17)(q10)abnormality is mainly associated with chronic myeloid leukemia(CML),myelodysplastic syndrome/myeloproliferative tumors(MDS/MPD),and acute myeloid leukemia(AML).The role of i(17)(q10)in AML is still unknown,the differences between AML and acute promyelocytic leukemia(APL)-like AML with i(17)(q10)need more research.This study aimed to investigate the clinical characteristics and laboratory evidence of 2 AML cases with i(17)(q10),similar to APL phenotype.CASE SUMMARY Both pediatric patients were males;case 1 had newly diagnosed AML,and case 2 showed relapsed tumor after 1 year of drug withdrawal.Bone marrow cell morphology,chromosome karyotype analysis,Fully-instrumented submersible housing test,immunological assays,molecular biological methods,and blood tumor panoramic gene test were performed.All-trans retinoic acid(ATRA)combined with arsenic acid(As2O3)were used in the first course of treatment.Bone marrow was dominated by abnormal promyelocytic granulocytes.Karyotype test revealed i(17)(q10)isochromosome.Immunological phenotype mainly included positive expressions of CD9,CD13,CD33,and CD38.Case 1 suffered intracranial hemorrhage after re-chemotherapy and died on D162.For case 2,on D145 and D265,bone marrow promyelocytic granulocytes accounted for 2%.Flow cytometric residual lesion detection showed no abnormal immunophenotype cells.The copy number of WT1 gene in two cases were 1087 and 1010,respectively,and the expression rates were 55.29% and 59.5%,respectively.CONCLUSION ATRA,As2O3,and chemotherapy may be ineffective in treating APL-like AML with i(17)(q10)but without t(15;17)and PML-RARA fusion gene.

Myeloid sarcoma as the only manifestation in a rare mixed lineage leukemia-fusion-driven acute myeloid leukemia:A case report

BACKGROUND The mixed lineage leukemia(MLL)-eleven-nineteen lysine-rich leukemia(ELL)fusion gene is a rare occurrence among the various MLL fusion genes.We present the first case in which myeloid sarcoma(MS)was the only manifestation of adult MLL-ELL-positive acute myeloid leukemia(AML).CASE SUMMARY We report a case of a 33-year-old male patient who was admitted in June 2022 with a right occipital area mass measuring approximately 7 cm×8 cm.Blood work was normal.The patient underwent right occipital giant subscalp mass excision and incisional flap grafting.Immunohistochemistry was positive for myeloperoxidase,CD43 and CD45 and negative for CD3,CD20,CD34,and CD56.The bone marrow aspirate showed hypercellularity with 20%myeloblasts.Flow cytometry showed that myeloblasts accounted for 27.21%of the nucleated cells,which expressed CD33,CD38,and CD117.The karyotype was 46,XY,t(11,19)(q23;p13.1),-12,+mar/46,XY.Next-generation sequencing showed a fusion of MLL exon 7 to exon 2 of ELL.A diagnosis of MLL-ELL-positive AML(M2 subtype)with subcutaneous MS was made.CONCLUSION MLL-ELL-positive AML with MS is a rare clinical entity.Additional research is needed to elucidate the molecular mechanisms of the pathogenesis of MS.

Murine models based on acute myeloid leukemia-initiating stem cells xenografting

Acute myeloid leukemia(AML) is an aggressive malignant disease defined by abnormal expansion of myeloid blasts. Despite recent advances in understanding AML pathogenesis and identifying their molecular subtypes based on somatic mutations, AML is still characterized by poor outcomes, with a 5-year survival rate of only 30%-40%, the majority of the patients dying due to AML relapse. Leukemia stem cells(LSC) are considered to be at the root of chemotherapeutic resistance and AML relapse. Although numerous studies have tried to better characterize LSCs in terms of surface and molecular markers, a specific marker of LSC has not been found, and still the most universally accepted phenotypic signature remains the surface antigens CD34+CD38- that is shared with normal hematopoietic stem cells. Animal models provides the means to investigate the factors responsible for leukemic transformation, the intrinsic differences between secondary post-myeloproliferative neoplasm AML and de novo AML, especially the signaling pathways involved in inflammation and hematopoiesis. However, AML proved to be one of the hematological malignancies that is difficult to engraft even in the most immunodeficient mice strains, and numerous ongoing attempts are focused to develop "humanized mice" that can support the engraftment of LSC. This present review is aiming to in-troduce the field of AML pathogenesis and the concept of LSC, to present the current knowledge on leukemic blasts surface markers and recent attempts to develop best AML animal models.

Therapy-Related Acute Myeloid Leukemia in A Primary Pulmonary Leiomyosarcoma Patient with Skin Metastasis

Primary pulmonary leiomyosarcoma （LMS） is a very unusual tumor.Although LMS has well-known metastatic potential,cutaneous metastasis is a remarkably uncommon.Exposure to cytotoxic agents could lead to ＂therapy-related myeloid neoplasm＂ （t-MN）.Starting from 2008,the World Health Organization （WHO） has adopted the term to cover the spectrum of malignant diseases previously known as therapy-related acute myeloid leukemia （t-AML）,therapy-related myelodysplastic syndrome （t-MDS） and therapy-related myelodysplastic/myelo-proliferative neoplasm （t-MDS/MPN）.We described the onset of t-MDS and progression to t-AML in one case diagnosed as primary pulmonary LMS with cutaneous metastasis.This patient achieved complete remission （CR） after three courses of IA regimen chemotherapy （idarubicin 5 mg/d,d 1-3;cytarabine 100 mg/d,d 1-5） and 1 course of HA chemotherapy regimen （homoharringtonine 3 mg/d,d 1-3;cytarabine 100 mg/d,d 1-7）.This case presents the natural course of therapy-related neoplasm and provides therapeutic experience for t-AML.

Higher PD-1 expression concurrent with exhausted CD8+ T cells in patients with de novo acute myeloid leukemia

Objective： To investigate the association between the T cell inhibitory receptor programmed death 1（PD-1）and T cell exhaustion status in T cells from patients with de novo acute myeloid leukemia（AML） and AML in complete remission（CR）.Methods：Surface expression of PD-1 and the exhaustion and immunosenescence markers CD244 and CD57 on CD3＋,CD4＋ and CD8＋ T cells from peripheral blood samples from 20 newly diagnosed,untreated AML patients and 10 cases with AML in CR was analyzed by flow cytometry.Twenty-three healthy individuals served as control.Results：A significantly higher percentage of PD-1＋ cells were found for CD3＋ T cells in the de novo AML group compared with healthy controls.In addition,an increased level of PD-1＋ CD8＋ T cells,but not PD-1＋ CD4＋,was found for CD3＋ T cells in the de novo AML and AML-CR samples.A higher percentage of CD244＋ CD4＋,CD244＋ CD8＋,CD57＋ CD4＋ and CD57＋ CD8＋ T cells was found in CD3＋ T cells in samples from those with de novo AML compared with those from healthy controls.Strong increased PD-1＋ CD244＋ and PD-1＋ CD57＋ coexpression was found for CD4＋ and CD8＋ T cells in the de novo AML group compared with healthy controls.Conclusions：We characterized the major T cell defects,including co-expression of PD-1 and CD244,CD57-exhausted T cells in patients with de novo AML,and found a particular influence on CD8＋ T cells,suggesting a poor anti-leukemia immune response in these patients.