C/EBPα-Induced MicroRNA 30c Inactivates Notch1 During Granulopoiesis and Is Downregulated In Acute Myeloid Leukemia

Abstract Abstract 2368 The transcription factor CCAAT Enhancer Binding Protein alpha (C/EBPα) is crucial for normal granulopoiesis and frequently disrupted in acute myeloid leukemia (AML). Loss of expression or function of C/EBPα leads to a block of myeloid differentiation. MicroRNAs inhibiting translation of mRNA into protein were identified as critical players in stem cell development. We and others have already shown that C/EBPα exerts its effects by regulating microRNAs such as miR-223 and miR-34a. In a global microRNA-array screen we found miR-30c as a novel target of C/EBPα during granulocytic differentiation. Wild-type C/EBPα-p42 upregulates miR-30c expression, whereas the C/EBPα-p30 mutant, found in AML, does not. Furthermore, G-CSF upregulates miR-30c expression during granulocytic differentiation of primary human CD34-positive progenitor cells. C/EBPα induces miR-30c and downregulates Notch1, a putative target of miR-30c, on protein, but not mRNA level. A block of miR-30c by LNAs prevents C/EBPα–induced downregulation of Notch1 protein expression. miR-30c is a tumor suppressor and downregulated in various subtypes of AML. In mice, miR-30c shows a high expression in LSK (including hematopoietic stem cells), GMP (granulocytic monocytic precursors) and granulocytes. An induced knock-out of C/EBPα in mice leads to a significantly downregulation of miR-30c expression in bone marrow cells. Our data indicates that C/EBPα-induced miR-30c inactivates Notch1 during granulopoiesis and is downregulated in AML. These data reveal the importance of deregulated microRNA expression in leukemia and may provide novel biomarkers and therapeutic targets in AML. Disclosures: No relevant conflicts of interest to declare.

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C/EBPα-Induced Microrna-30c Directly Targets Notch1 During Granulopoiesis and Is Repressed in Acute Myeloid Leukemia

Blood ◽

10.1182/blood.v120.21.3514.3514 ◽

2012 ◽

Vol 120 (21) ◽

pp. 3514-3514

Author(s):

Christiane Katzerke ◽

Vikas Madan ◽

Dennis Gerloff ◽

Daniela Braeuer-Hartmann ◽

Jens-Uwe Hartmann ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Protein Expression ◽

Myeloid Leukemia ◽

Bone Marrow Cells ◽

Locked Nucleic Acid ◽

Luciferase Reporter ◽

Loss Of Function ◽

Granulocytic Differentiation ◽

Knock Out ◽

Acute Myeloid

Abstract Abstract 3514 The transcription factor CCAAT Enhancer Binding Protein alpha (C/EBPα) is crucial for normal granulopoiesis and frequently disrupted in acute myeloid leukemia (AML). Mutations in the CEBPA gene are reported for about 10% of all AML. Loss of function of C/EBPα leads to a block of myeloid differentiation. MicroRNAs (miR) inhibiting translation of mRNA into protein were identified as critical players in granulocytic differentiation. We and others have already shown that C/EBPα exerts its effects by regulating miRNAs such as miR-223 and miR-34a. In a global microRNA-array we found miR-30c as a novel most important target of C/EBPα during granulopoiesis. Wild-type C/EBPα-p42 up regulates miR-30c expression, whereas the C/EBPα-p30 mutant, found in AML, does not. Furthermore, miR-30c expression is up regulated by G-CSF during granulocytic differentiation of primary human CD34-positive progenitor cells and down regulated in various subtypes of AML. Among these, miR-30c is significantly down regulated in samples from AML with normal karyotype and CEBPA mutations compared to AML patients with CEBPA wildtype. In mice, miR-30c shows a high expression in GMP and granulocytes. An induced tissue specific knock-out of C/EBPα in mice leads to a significant suppression of miR-30c expression in bone marrow cells. A luciferase reporter assay identifies NOTCH1 as a direct target of miR-30c as evident by its binding to the 3'UTR. Recent studies show that Notch1 blocks protein expression of C/EBPα-p42 by activation of Tribbles homolog 2 (Trib2). On the other hand, Proteins of Notch1 and Trib2 are down regulated by C/EBPα-p42. A block of miR-30c by locked nucleic acid (LNA) oligonucleotides prevents C/EBPα–induced downregulation of Notch1 protein expression, thus, miR-30c is necessary for C/EBPα to block NOTCH1. In this direction, the network leads to a block of granulopoiesis and further to leukemogenesis. Our study indicates that C/EBPα-induced miR-30c inactivates Notch1 during granulopoiesis and is down regulated in AML. This data stress the important role of deregulated miRNA expression in leukemia and may provide novel biomarkers and therapeutic targets in AML. Disclosures: Schnittger: MLL Munich Leukemia Laboratory: Equity Ownership.

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Inhibition of HDAC8 Reactivates p53 and Abrogates Leukemia Stem Cell Activity in CBFβ-SMMHC Associated Acute Myeloid Leukemia

Blood ◽

10.1182/blood.v124.21.363.363 ◽

2014 ◽

Vol 124 (21) ◽

pp. 363-363

Author(s):

Jing Qi ◽

Qi Cai ◽

Sandeep Singh ◽

Ling Li ◽

Hongjun Liu ◽

...

Keyword(s):

Bone Marrow ◽

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Bone Marrow Cells ◽

Conflicts Of Interest ◽

Cell Activity ◽

Disease Free Survival ◽

Hematopoietic Stem ◽

The Impact ◽

Acute Myeloid

Abstract The inv(16)-created CBFβ-SMMHC fusion protein inhibits differentiation of hematopoietic stem and progenitor cells (HSPCs) and creates pre-leukemic populations predisposed to acute myeloid leukemia (AML) transformation. However, the molecular mechanism underlying the leukemogenic function of CBFβ-SMMHC has been elusive. Given the low TP53 mutation rate in AML, alternative mechanisms disrupting p53 function are expected. We showed thatCBFβ-SMMHC impairs p53 acetylation and p53 target gene activation through formation of an aberrant protein complex with p53 and HDAC8 (Blood, 120: A772; 122(21): 224). We now show that CBFβ-SMMHC binds to p53 and HDAC8 independently through distinct regions and that HDAC8 mediates the deacetylation of p53 associated with CBFβ-SMMHC. In addition, we generated mice carrying a floxed Hdac8 (Hdac8f) allele and crossed with Cbfb56M/+/Mx1-Cre (Kuo YH et al, Cancer Cell 2006). Deletion of Hdac8 signifiacntly (p<0.0001) reduced the incidence of AML and prolonged disease-free survival. Pharmacologic inhibition of HDAC8 activity with HDAC8-selective inhibitors (HDAC8i) reactivates p53 and selectively induces apoptosis of inv(16)+ AML CD34+ cells while sparing normal HSPCs. To test the effect of HDAC8i on LSC engraftment and leukemia-initiating capacity, we generated Cbfb56M/+/Mx1-Cre mice with a Cre-reporter line expressing tdTomato fluorescence protein following Cre-mediated recombination. AML cells (dTomato+/cKit+) treated with HDAC8i (22d) ex vivo showed reduced engraftment (p=0.025) and enhanced survival (p=0.025) in transplanted mice. To examine whether HDAC8i 22d treatment affects the engraftment capacity on surviving cells, we transplanted equal number (2 x 106) of AML cells treated with either 22d or vehicle in another cohort of mice (n=4). We show that HDAC8i 22d treatment reduced the engraftment of dTomato+/cKit+ AML cells and enhanced survival, suggesting that the engraftment capacity is altered in addition to reducing AML cell survival. We next performed preclinical studies to determine the efficacy of in vivo administration of HDAC8i 22d. AML transplanted mice were randomized into two groups, one group treated with vehicle and the other treated with HDAC8i 22d for 2 weeks. Flow cytometry analysis revealed significantly reduced frequency (p=0.0097) and number (p=0.0101) of dTomato+/cKit+ AML cells in the bone marrow and spleen of 22d treated mice compared to vehicle treated group. To further assess the impact on LSC activity, we transplanted bone marrow cells from these treated mice into secondary recipients and analyzed for AML engraftment. Significant reduction in the frequency (p<0.0001) and the number (p=0.0006) of dTomato+/cKit+ AML cells was observed in the bone marrow and spleen. Furthermore, HDAC8i 22d treated transplants showed no signs of leukemia while vehicle treated transplants are moribund with aggressive AML. These results indicate that HDAC8 inhibition by 22d treatment effectively eliminates engraftment and leukemia-initiating capacity of AML LSCs. In conclusion, our studies identify a novel post-translational p53-inactivating mechanism and demonstrate selective HDAC8 inhibition as a promising approach to target inv(16)+ AML LSCs. Disclosures No relevant conflicts of interest to declare.

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Combination of Mitoxantrone,Ara-C and Homoharringtonine In Treatment of Refractory and Relapsed Acute Myeloid Leukemia

Blood ◽

10.1182/blood.v118.21.4294.4294 ◽

2011 ◽

Vol 118 (21) ◽

pp. 4294-4294

Author(s):

Jianda Hu ◽

Tingbo Liu ◽

Chunxia Cai ◽

Xinji Chen ◽

Buyuan Chen

Keyword(s):

Drug Resistance ◽

Acute Myeloid Leukemia ◽

Stem Cell ◽

Stem Cell Transplantation ◽

Cell Transplantation ◽

Median Time ◽

Myeloid Leukemia ◽

Conflicts Of Interest ◽

Hematopoietic Stem ◽

Acute Myeloid

Abstract Abstract 4294 Advances in effective chemotherapy have improved clinical outcomes in acute leukemia in recent years. 5-year survival rate approaches 50–60% for acute myeloid leukemia (AML). However, the prognosis remains poor for patients who are relapsed or refractory to first-line therapy. Drug resistance and early disease recurrence are major contributing factors in the limited survival of patients with AML. The strategy for treating these patients is through reinduction chemotherapy followed by allogeneic stem cell transplantation. New combinations of different agents were employed in refractory patients to overcome drug resistance. The current study is to evaluate the efficacy of a MAH regimen comprising Mitoxantrone,Ara-C and Homoharringtonine in refractory or relapsed AML. 37 patients aged 14–65 years with refractory or relapsed AML (15 refractory AML patients, 22 relapsed AML patients) were treated with the MAH regimen(Mitoxantrone 10mg qd, iv.gtt, for 2□‘3 days;Ara-C 100mg bid, iv.gtt, for 5□‘7 days; Homoharringtonine 4mg qd iv.gtt, for 5□‘7 days). Chemotherapy duration lasted for 5 or 7days depended on bone marrow cellurarity. 15 (40.5%)and 1 (2.7%) patients achieved complete remission (CR) and partial remission (PR) respectively. The overall response rate was 43.2%. There was no relation between remission duration and previous chemotherapy. All patients who achieved CR received a consolidation and intensification therapy. The median overall survival (OS) for all patients was 97 days (range 18–487 d). For the patients who were in CR or PR,the median relapse-free survival(RFS) was 147 days(range 4 to 341 d). All patients experienced profound myelosuppression. The most common observed side effect of the regimen was infection because of grade ‡W neutropenia, which could be observed in 33 patients(89.1%). 4 patients died in aplasia due to severe infection and brain hemorrhage. In patients achieving remission, the median time to reach absolute neutrophil count (ANC) more than 0.5×109/l was (16.0±6.4)d. Platelet levels of more than 20×109/l were achieved in a median time of (12.7±6.2)d. Nonhematological side effects, consisting mainly of gastrointestinal toxicity(21/37,56.8%) and transient liver ALT and AST increase (4/37), were generally mild to moderate and tolerated. To a conclusion, MAH regimen can be employed in treatment of the refractory or relapsed AML patients who were not responded to other regimen. It is effective and is good tolerant.It could provide some refractory patients the chance to receive hematopoietic stem cell transplantation. Disclosures: No relevant conflicts of interest to declare.

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Expression of CD56 Is an Independent Prognostic Factor to Predict Relapse in Acute Myeloid Leukemia with t(8;21): Results of Japan Adult Leukemia Study Group (JALSG) AML97 Protocol.

Blood ◽

10.1182/blood.v120.21.2511.2511 ◽

2012 ◽

Vol 120 (21) ◽

pp. 2511-2511

Author(s):

Noriyoshi Iriyama ◽

Yoshihiro Hatta ◽

Jin Takeuchi ◽

Yoshiaki Ogawa ◽

Shigeki Ohtake ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Conflicts Of Interest ◽

Performance Status ◽

Univariate Analysis ◽

Rank Test ◽

Hematopoietic Stem ◽

Wbc Count ◽

Adverse Factor ◽

Acute Myeloid

Abstract Abstract 2511 Background: Although prognosis of acute myeloid leukemia (AML) with t(8;21) is better than other types of AML, outcome of the patients has not been satisfied. Previously, aberrant antigen expression has been reported as risk factor for AML with t(8;21). However, in the reported series, number of cases was not large enough and chemotherapy regimens were variable. We investigated the association of prognosis and several biomarkers including immunophenotype, WBC count, age, and performance status for large number of AML patients with t(8;21) uniformly treated in JALSG AML97 regimen. Patients and Methods: Seven hundred eighty-nine eligible AML patients were evaluated for the multicenter JALSG AML97 study. Adult patients with de novo AML except for APL, ages 15–64 years, were registered consecutively from 103 institutions that participated in JALSG from December 1997 to July 2001. One hundred forty-four patients with AML with t(8;21) were analyzed in this study with a median 1205 days of observation term from diagnosis. Complete remission (CR), relapse-free survival (RFS), and overall survival (OS) rates were analyzed by Fisher's exact test and log-rank test. Factors that would affect clinical outcome were analyzed by multivariate Cox proportional hazard regression model. Results: AML with t(8;21) frequently expressed CD19, CD34, and CD56 compared to other subtypes of AML. CD11b was rarely expressed. Expression of CD19 favorably affected on CR rate (96% in CD19 positive and 87% in negative patients, p<0.05). Univariate analysis showed WBC>20×109/L, CD19 negativity, and CD56 positivity were adverse factors for RFS. CD56 expression was the only independent adverse factor for RFS by multivariate analysis (73.7% in CD56 negative and 48.2% in CD56 positive patients at 3 yrs) although its expression did not affect on OS. There was no difference of age, sex, WBC count, presence or absence of Auer rod, performance status, or CD15 expression between CD56 positive and negative cases. Expression of CD19 was more common in CD56 negative patients (50% in CD56 negative and 30.6% in CD56 positive patients, p<0.05). Conclusions: We demonstrated that the expression of CD56 was a distinctive adverse factor in a large number of AML patients with t(8;21) treated with JALSG AML97 regimen. CD56 positive AML patients with t(8;21) are possible candidates for hematopoietic stem cell transplantation. Disclosures: No relevant conflicts of interest to declare.

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CXCR4 Invalidation Limits the MLL-ENL Induced Leucemogenesis in Vivo

Blood ◽

10.1182/blood.v120.21.4089.4089 ◽

2012 ◽

Vol 120 (21) ◽

pp. 4089-4089

Author(s):

Yanyan Zhang ◽

Hadjer Abdelouahab ◽

Aline Betems ◽

Monika Wittner ◽

William Vainchenker ◽

...

Keyword(s):

Bone Marrow ◽

Acute Myeloid Leukemia ◽

Survival Time ◽

Median Survival ◽

Median Survival Time ◽

Myeloid Leukemia ◽

Conflicts Of Interest ◽

Hematopoietic Stem ◽

Acute Myeloid

Abstract Abstract 4089 The receptor CXCR4 and its ligand SDF-1 play major physiological roles especially on hematopoietic stem cells homing and retention. Many studies have implicated CXCR4 in the invasion by tumor cells of organs that produce SDF-1. In acute myeloid leukemia, the physiological role of CXCR4 is not fully understood. We used retrovirus to express MLL-ENL oncogene in CXCR4+/+ and CXCR4−/− hematopoietic primitive cells (Lin- isolated from fetal liver) and showed that CXCR4 is dispensable for generation of immortalized colonies in vitro. To determine CXCR4 function in vivo, CXCR4+/+ and CXCR4−/− transformed cells were transplanted into lethally irradiated mice. Whatever their phenotype, the recipient developed a myelo-monocytique leukemia characterized by their expression of Gr-1 and Mac-1. As expected, all recipients of MLL-ENL transduced CXCR4+/+ cells were moribund within 35 to 80 days post transplant (median survival time: 50 days). Strikingly, recipients of MLL-ENL transduced CXCR4−/− cells showed significantly increased lifespan, with a median survival time of 90 days. The cellularity of the peripheral blood of recipients of MLL-ENL transduced cells displayed considerable increases over time although this increase was much lower in CXCR4−/− than in CXCR4+/+ chimera. Bone marrow of MLL-ENL transduced CXCR4−/− chimera had moderately decreased numbers of mononuclear cells. There were important numbers of leukemic CD45.2+/Gr1+/Mac1+/c-kit+ cells in spleen from MLL-ENL CXCR4+/+ chimera which suggested that CXCR4 is important for leukemic progenitors cells retention in the bone marrow and especially in the spleen. The homing capacity of transduced CXCR4+/+ cells is comparable to the CXCR4−/− cells. Finally, more DNA damages were found in the BM cells of MLL-ENL CXCR4−/− chimera. All these results were confirmed by treating of MLL-ENL CXCR4+/+ chimera with CXCR4 inhibitor (TN140). These results demonstrated that in absence of CXCR4, the cells transduced by oncogene MLL-ENL are capable of generating leukemia in the recipients. However, mice transplanted with MLL-ENL transduced CXCR4−/− FL cells developed acute myeloid leukemia with reduced aggressiveness and organ infiltration, which is associated with induced differentiation and DNA instability. These results indicated that the MLL-ENL progenitors are dependent on CXCR4 for their maintenance in the BM and spleen suggesting that CXCR4 inhibitors might have potential therapeutic applications. Disclosures: No relevant conflicts of interest to declare.

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A Novel Path for ATRA Differentiation Therapy in Acute Myeloid Leukemia with Isocitrate Dehydrogenase Mutations

Blood ◽

10.1182/blood.v124.21.3727.3727 ◽

2014 ◽

Vol 124 (21) ◽

pp. 3727-3727

Author(s):

Jean-Emmanuel Sarry ◽

Helena Boutzen ◽

Christian Récher

Keyword(s):

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Conflicts Of Interest ◽

Negative Regulator ◽

Granulocytic Differentiation ◽

Induced Differentiation ◽

Idh1 R132h ◽

Recurrent Mutations ◽

Idh Mutations ◽

Acute Myeloid

Abstract Acute myeloid leukemia (AML) is characterized by accumulation of malignant blasts with impaired differentiation programs due to recurrent mutations, among which IDH mutations occur in 15% of AML patients. These mutations lead to a block in erythroid commitment while they may also bias hematopoietic differentiation to myeloid lineage. Interestingly, Lyn tyrosine kinase is required for erythroid differentiation and we have observed a reduction of Lyn expression in the presence of IDH1-R132H mutation. It is also a negative regulator of ATRA-induced granulocytic differentiation. Accordingly, we hypothesized that IDH mutations may sensitize AML cells to ATRA-induced differentiation. Here, we report that clinically achievable doses of ATRA are sufficient to trigger differentiation specifically on AML cell lines, primary patient samples and xenograft mice models carrying IDH1 mutation as observed by an increase in CD11b expression, granulocytic enzyme activity and morphologic changes in May-Grunwald-Giemsa staining. We also showed that ATRA-induced terminal granulocytic differentiation increases apoptosis while decreases proliferation and colony formation specifically in IDH1 mutant cells. Moreover, inhibition of IDH1-R132H activity reduced ATRA-sensitivity while increasing expression of IDH mutation correlated with highest ATRA sensitivity. Furthermore, treatment with a cell-permeable form of the oncometabolite specifically produced by the mutant (eg. 2-HydroxyGlutarate) sensitized AML cells to ATRA-induced differentiation. Finally, because ATRA-induced differentiation triggers a transient increase of Lyn activation, its association with Lyn inhibitors synergistically increased ATRA-induced differentiation of IDH mutant blasts. In summary, our results showed that IDH mutations by producing 2-HG sensitized leukemic blasts to ATRA and that this synergizes with Lyn inhibition. Since 2HG concentration reaches millimolar in AML patient serum and is 100-fold higher in IDH mutated patients than in non-mutated ones, we would predict a strong efficacy and specificity of ATRA. Furthermore, as IDH mutations are systematically conserved at relapse, this therapeutic strategy might be promising to achieve a long-term remission specifically for this AML patient subgroup. Disclosures No relevant conflicts of interest to declare.

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Different regulation of PARP1, PARP2, PARP3 and TRPM2 genes expression in acute myeloid leukemia cells

10.21203/rs.2.19004/v1 ◽

2019 ◽

Author(s):

Paulina Gil-Kulik ◽

Ewa Dudzińska ◽

Elżbieta Radzikowska-Büchner ◽

Joanna Wawer ◽

Mariusz Jojczuk ◽

...

Keyword(s):

Gene Expression ◽

Bone Marrow ◽

Acute Myeloid Leukemia ◽

Peripheral Blood ◽

Myeloid Leukemia ◽

Mrna Level ◽

Hematopoietic Stem ◽

Genes Expression ◽

Acute Myeloid Leukemia Cells ◽

Acute Myeloid

Abstract Acute myeloid leukemia (AML) is a heterogenic lethal disorder characterized by the accumulation of abnormal myeloid progenitor cells in the bone marrow, which results in hematopoietic failure. Despite various efforts in detection and treatment, many patients with AML die of this cancer. That is why it is important to develop novel therapeutic options, employing strategic target genes involved in apoptosis and tumor progression. The aim of the study was to evaluate PARP1, PARP2, PARP3, and TRPM2 gene expression at the mRNA level in the cells of the hematopoietic system of the bone marrow in patients with acute myeloid leukemia, bone marrow collected from healthy patients, peripheral blood of healthy individuals, and hematopoietic stem cells from the peripheral blood after mobilization.Results: The results found that the bone marrow cells of patients with acute myeloid leukemia (AML) show over expression of PARP1 and PARP2 genes and decreased TRPM2 gene expression. In the hematopoietic stem cells derived from the normal marrow and peripheral blood after mobilization, the opposite situation was observed, i.e. TRPM2 gene showed increased expression while PARP1 and PARP2 gene expression was reduced. We observed the positive correlations between PARP1, PARP2, PARP3, and TRPM2 genes expression in the group of mature mononuclear cells derived from the peripheral blood and in the group of bone marrow-derived cells. In AML cells significant correlations were not observed between the expression of the examined genes.Conclusions: Our research suggests that in physiological conditions in the cells of the hematopoietic system there is mutual positive regulation of PARP1, PARP2, PARP3, and TRPM2 genes expression. PARP1, PARP2, and TRPM2 genes at mRNA level deregulate in acute myeloid leukemia cells.

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Combination of Cladribine, Cytarabine and Topotecan (CLAT) for Relapsed or Refractory Acute Myeloid Leukemia

Blood ◽

10.1182/blood.v126.23.4897.4897 ◽

2015 ◽

Vol 126 (23) ◽

pp. 4897-4897

Author(s):

Xiaomei Chen ◽

Jianyu Weng ◽

Yulian Wang ◽

Chengxin Deng ◽

Chengwei Luo ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Natural Science ◽

Myeloid Leukemia ◽

Conflicts Of Interest ◽

Science And Technology ◽

Technology Planning ◽

Hematopoietic Stem ◽

Planning Project ◽

Refractory Acute Myeloid Leukemia ◽

Acute Myeloid

Abstract Xiaomei Chen and Jianyu Weng contributed equally to this study. The outcomes ofrelapsed or refractory acute myeloid leukemia (RR-AML) are poor and effective salvage regimens are urgently needed. We present a study of 14 patients with RR-AML (median age 42years, range 18-65years; male n=12, female n= 2) treated with CLAT regimen, which consisted of cladribine 5mg/m² per day i.v. 2-3 hour on days 1-5, cytarabine 1.0g/m² per day i.v. 4 hours after cladribine on days 1-5, topotecan 1.25mg/m² per day i.v. 4 hours after cytarabine on days1-5 and G-CSF 300ug per day subcutaneous injection on days until neutrophile granulocyte recovery. Total of fourteen patients were included into the study from June 2013 to June 2015, Two (14.3%) patients were relapsed and twelve (85.7%) patients were refractory, 4 of 14 patients were relapsed or refractory after allogeneic-HSCT. Two patients died of invasive fungal infection before the assessment. Seven patients (58.3%) achieved complete remission (CR), and one patient (8.3%) achieved partial remission (PR), the rest patients (33.3%) did not respond (NR). The overall response rate was 66.7%. Following CLAT treatment, four patients with CR underwent allogeneic hematopoietic stem cell transplantation (HSCT) or microtransplantation. The median relapse-free survival (RFS) for RR-AML patients receiving CLAT regimen was 8.6 (range 2-16) months. Thirteen patients developed grade 4 granulocytopenia and thrombocytopenia, the median duration was 13(range 2 to 21) days and12 (range 2 to 21) days, respectively. The most common non-hematological side effects included nausea, vomiting, diarrhoea, and were grade 1/2. The CLAT regimen seems promising for the treatment of patients, and it was well tolerated. This regimen offers an alternative treatment for those patients with RR-AML who have received severe intensive treatment, especially with anthracycline-containing chemotherapy. The project was sponsored by grants from National Natural Science Foundation of China (No. 30972790; No.81270648; No.81370665; No.81300446) Provincial Natural Science Foundation of Guangdong (No. S2012010009560) Provincial Science and Technology Planning Project of Guangdong (No.2013B021800186; No.2013B021800201), and Science and Technology Planning Project of Guangzhou (No. 201400000003-4, 201400000003-1). Disclosures No relevant conflicts of interest to declare.

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Different regulation of PARP1, PARP2, PARP3 and TRPM2 genes expression in acute myeloid leukemia cells

10.21203/rs.2.19004/v4 ◽

2020 ◽

Author(s):

Paulina Gil-Kulik ◽

Ewa Dudzińska ◽

Elżbieta Radzikowska-Büchner ◽

Joanna Wawer ◽

Mariusz Jojczuk ◽

...

Keyword(s):

Gene Expression ◽

Bone Marrow ◽

Acute Myeloid Leukemia ◽

Peripheral Blood ◽

Myeloid Leukemia ◽

Mrna Level ◽

Hematopoietic Stem ◽

Genes Expression ◽

Acute Myeloid Leukemia Cells ◽

Acute Myeloid

Abstract Background: Acute myeloid leukemia (AML) is a heterogenic lethal disorder characterized by the accumulation of abnormal myeloid progenitor cells in the bone marrow which results in hematopoietic failure. Despite various efforts in detection and treatment, many patients with AML die of this cancer. That is why it is important to develop novel therapeutic options, employing strategic target genes involved in apoptosis and tumor progression.Methods: The aim of the study was to evaluate PARP1, PARP2, PARP3, and TRPM2 gene expression at mRNA level using qPCR method in the cells of hematopoietic system of the bone marrow in patients with acute myeloid leukemia, bone marrow collected from healthy patients, peripheral blood of healthy individuals, and hematopoietic stem cells from the peripheral blood after mobilization. Results: The results found that the bone marrow cells of the patients with acute myeloid leukemia (AML) show overexpression of PARP1 and PARP2 genes and decreased TRPM2 gene expression. In the hematopoietic stem cells derived from the normal marrow and peripheral blood after mobilization, the opposite situation was observed, i.e. TRPM2 gene showed increased expression while PARP1 and PARP2 gene expression was reduced. We observed positive correlations between PARP1, PARP2, PARP3, and TRPM2 genes expression in the group of mature mononuclear cells derived from the peripheral blood and in the group of bone marrow-derived cells. In AML cells significant correlations were not observed between the expression of the examined genes. In addition, we observed that the reduced expression of TRPM2 and overexpression of PARP1 are associated with a shorter overall survival of patients, indicating the prognostic significance of these genes expression in AML.Conclusions: Our research suggests that in physiological conditions in the cells of the hematopoietic system there is mutual positive regulation of PARP1, PARP2, PARP3, and TRPM2 genes expression. PARP1, PARP2, and TRPM2 genes at mRNA level deregulate in acute myeloid leukemia cells.

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Different regulation of PARP1, PARP2, PARP3 and TRPM2 genes expression in acute myeloid leukemia cells

10.21203/rs.2.19004/v2 ◽

2020 ◽

Author(s):

Paulina Gil-Kulik ◽

Ewa Dudzińska ◽

Elżbieta Radzikowska-Büchner ◽

Joanna Wawer ◽

Mariusz Jojczuk ◽

...

Keyword(s):

Gene Expression ◽

Bone Marrow ◽

Acute Myeloid Leukemia ◽

Peripheral Blood ◽

Myeloid Leukemia ◽

Mrna Level ◽

Hematopoietic Stem ◽

Genes Expression ◽

Acute Myeloid Leukemia Cells ◽

Acute Myeloid

Abstract Background Acute myeloid leukemia (AML) is a heterogenic lethal disorder characterized by the accumulation of abnormal myeloid progenitor cells in the bone marrow which results in hematopoietic failure. Despite various efforts in detection and treatment, many patients with AML die of this cancer. That is why it is important to develop novel therapeutic options, employing strategic target genes involved in apoptosis and tumor progression. Methods The aim of the study was to evaluate PARP1, PARP2, PARP3, and TRPM2 gene expression at mRNA level using qPCR method in the cells of hematopoietic system of the bone marrow in patients with acute myeloid leukemia, bone marrow collected from healthy patients, peripheral blood of healthy individuals, and hematopoietic stem cells from the peripheral blood after mobilization. Results The results found that the bone marrow cells of the patients with acute myeloid leukemia (AML) show overexpression of PARP1 and PARP2 genes and decreased TRPM2 gene expression. In the hematopoietic stem cells derived from the normal marrow and peripheral blood after mobilization, the opposite situation was observed, i.e. TRPM2 gene showed increased expression while PARP1 and PARP2 gene expression was reduced. We observed positive correlations between PARP1, PARP2, PARP3, and TRPM2 genes expression in the group of mature mononuclear cells derived from the peripheral blood and in the group of bone marrow-derived cells. In AML cells significant correlations were not observed between the expression of the examined genes. In addition, we observed that the reduced expression of TRPM2 and overexpression of PARP1 are associated with a shorter overall survival of patients, indicating the prognostic significance of these genes expression in AML. Conclusions Our research suggests that in physiological conditions in the cells of the hematopoietic system there is mutual positive regulation of PARP1, PARP2, PARP3, and TRPM2 genes expression. PARP1, PARP2, and TRPM2 genes at mRNA level deregulate in acute myeloid leukemia cells.

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