The Size of the Dendritic Cell Population At Diagnosis Worsens Prognosis in Acute Myeloid Leukemia – Bigger Is Not Better

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 4870-4870
Author(s):  
Marta I Pereira ◽  
Ana I Espadana ◽  
Emília Cortesão ◽  
Gilberto P Marques ◽  
Catarina Geraldes ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
De Novo ◽  
World Health ◽  
Biological Behavior ◽  
Newly Diagnosed ◽  
Secondary Aml ◽  
De Novo Aml ◽  
Dc Component ◽  
Acute Myeloid

Abstract Abstract 4870 Background: Dendritic cells (DC) are a heterogeneous population of lineage-negative antigen-presenting cells derived from CD34+ hematopoietic progenitors, present in tissue, blood and bone marrow (BM), where plasmacytoid DC (pDC) are a normal finding, representing 0.2 ± 0.1% of cell populations (Matarraz et al, 2010). DC neoplasms include solid tumors (such as DC sarcomas) and an entity classified by the World Health Organization (2008) as an acute myeloid leukemia (AML)-related precursor neoplasm: blastic pDC neoplasm/leukemia, an aggressive disease with poor prognosis, with no clinical trials to orient consensus regarding the most effective treatment; it is usually chemo-resistant, although some cases respond to AML-like regimens and allogeneic hematopoietic stem cell transplant. It is not clear if the presence of an increased DC population in non-DC AML confers pDC neoplasm-like biological characteristics to the former. Aims: This study aims to evaluate whether an increase in the size of DC populations in newly-diagnosed non-DC AML affects the latter's biological behavior, as represented by the overall survival (OS) of patients with the disease. Methods: We reviewed all AML diagnosed in our Hospital between January 1st 2008 and December 31st 2010, identifying 146 patients. We excluded 9 patients who had no flow cytometry immunophenotyping (IP) performed, and 7 whose first IP was performed after treatment was instituted. In that time frame, we also diagnosed 4 pDC neoplasms. Of the 130 patients included, 91 had their presenting IP performed on BM aspirate, while the remaining 39 were phenotyped on blood samples. The size of the DC populations and blastic DC maturation were determined on these samples. Patients were classified into 2 groups according to the size of the DC component; one (the Non-DC Group) had a DC component of up to 0.3% (in practice, the highest value in this group was 0.2%); the other (DC Group) had a percentage over this limit (the lowest value being 1.0%). OS data was determined for both groups; special consideration was given to age strata, separating patients under 65 years of age (Under-65) from those 65 or older (Over-65) and etiology (distinguishing de novo AML from AML secondary to therapy, myelodysplasia or myeloproliferative diseases). The percentage of DC identified by IP did not influence nor alter the type of treatment instituted. Results: We found that the presence of a DC component above the normal BM interval (as determined by Matarraz et al) was associated with a significantly decreased OS, with patients with DC components over 0.3% presenting with a median OS of 2.4 months (mean: 6.4 ± 1.6) and those with a component under 0.3% with a median OS of 8.6 months (mean: 17.0 ± 1.9) (p = 0.033). In our series, patients Over-65 had a median OS of 2.9 months (mean = 6.9 ± 1.0) and those Under-65 a median of 21.3 months (mean = 22.5 ± 2.5), p < 0.001. The differences in OS according to DC component were attenuated in patients Over-65 (median = 1.8 vs. 3.9 months, p = NS), whereas in patients Under-65 the median survival was 2.7 months (mean: 8.7 ± 2.9) for the DC Group and 24.4 months (mean: 24.3 ± 2.7) for the non-DC Group (p = 0.035). The differences in OS were also significant for de novo AML (median = 2.4 vs. 16.0 months, mean = 4.7 ± 1.9 vs. 20.5 ± 2.6, p = 0.017), but not statistically relevant for secondary AML (median = 4.4 vs. 5.5 months, mean = 8.4 vs. 10.8, p = NS). Discussion: In this study, we found that an increase in the size of the DC component as determined by IP at diagnosis on newly-diagnosed AML had a negative impact on prognosis, with a significant decrease in median and mean OS in patients with a percentage of DC over the upper limit of the normal interval. We also determined that the decreased survival was primarily attributed to the better-prognosis groups (patients under 65 and with de novo AML), whereas the effect of the worsened prognosis was attenuated in those patients with a bad prognosis at the outset (patients over 65 and with secondary AML). If data from DC neoplasms could be extrapolated, we could suggest that AML with increased DC components are less chemo-sensitive, which would explain the OS differences found in the Under-65 group, as well as the no-difference found in the Over-65 Group, which is frequently undertreated due to comorbidities. Conclusion: Our study suggests that the size of the DC component at diagnosis as determined by IP is a new prognostic marker predictive of decreased survival. Disclosures: No relevant conflicts of interest to declare.

scholarly journals TP53 mutation in newly diagnosed acute myeloid leukemia and myelodysplastic syndrome

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Pimjai Niparuck ◽  
Pornnapa Police ◽  
Phichchapha Noikongdee ◽  
Kanchana Siriputtanapong ◽  
Nittaya Limsuwanachot ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Myelodysplastic Syndrome ◽  
Myeloid Leukemia ◽  
Tp53 Mutation ◽  
De Novo ◽  
Complex Karyotype ◽  
Newly Diagnosed ◽  
Secondary Aml ◽  
De Novo Aml ◽  
Acute Myeloid

Abstract Objectives TP53 mutation is found frequently in therapy related acute myeloid leukemia (AML)/ myelodysplastic syndrome (MDS), AML and MDS patients with monosomy or complex karyotype. However, the prevalence and treatment outcome in TP53 mutated AML/MDS patients in Asian population are scarce. We therefore conducted this study to analyze the prevalence and the treatment outcomes of TP53 mutation in AML and MDS-EB patients. Methods Patients with newly diagnosed AML and MDS-EB were recruited, extraction of deoxyribonucleic acid from bone marrow samples were done and then performing TP53 mutation analysis, using MassArray® System (Agena Bioscience, CA, USA). Results A total of 132 AML/MDS patients were recruited, patients with de novo AML, secondary AML, MDS-EB1, MDS-EB2 and T-AML/MDS were seen in 66, 13, 9, 9 and 3%, respectively. TP53 mutation was found in 14 patients (10.6%), and prevalence of TP53 mutation in T-AML/MDS, secondary AML, de novo AML and MDS-EB patients were 50, 17.6, 9.2 and 8%, respectively. Three patients had double heterozygous TP53 mutation. Mutated TP53 was significantly detected in patients with monosomy and complex chromosome. Common TP53 mutation were R290C, T220C, A249S and V31I which V31I mutation was reported only in Taiwanese patients. Most variant allele frequency (VAF) of TP53 mutation in the study were greater than 40%. Three year-overall survival (OS) in the whole population was 22%, 3y-OS in AML and MDS-EB patients were 22 and 27%, respectively. The 1y-OS in patients with TP53-mutant AML/MDS were shorter than that in TP53 wild-type patients, 14% versus 50%, P = 0.001. In multivariate analysis, factors affecting OS in 132 AML/MDS patients was mutant TP53 (P = 0.023, HR = 1.20–7.02), whereas, WBC count> 100,000/μL (P = 0.004, HR = 1.32–4.16) and complex karyotype (P = 0.038, HR = 1.07–9.78) were associated with shorter OS in AML patients. Discussion In this study, the prevalence of TP53 mutation in de novo AML and MDS-EB patients were low but it had impact on survival. Patients with monosomy or complex karyotype had more frequent TP53 mutation.

scholarly journals TP53 Mutation in Newly Diagnosed Acute Myeloid Leukemia and Myelodysplastic Syndrome

2021 ◽  
Author(s):  
Pimjai Niparuck ◽  
Pornnapa Police ◽  
Phichchapha Noikongdee ◽  
Kanchana Siriputtanapong ◽  
Nittaya Limsuwanachot ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Myelodysplastic Syndrome ◽  
Myeloid Leukemia ◽  
Tp53 Mutation ◽  
De Novo ◽  
Complex Karyotype ◽  
Newly Diagnosed ◽  
Secondary Aml ◽  
De Novo Aml ◽  
Acute Myeloid

Abstract Objectives: TP53 mutation is found frequently in therapy related acute myeloid leukemia (AML)/ myelodysplastic syndrome (MDS), AML and MDS patients with monosomy or complex karyotype. However, the prevalence and treatment outcome in TP53 mutated AML/MDS patients in Asian population are scarce. We therefore conducted this study to analyze the prevalence and the treatment outcomes of TP53 mutation in AML and MDS-EB patients. Methods: Patients with newly diagnosed AML and MDS-EB were recruited, extraction of deoxyribonucleic acid from bone marrow samples were done and then performing TP53 mutation analysis, using MassArray® System (Agena Bioscience, CA, USA). Results: A total of 132 AML/MDS patients were recruited, patients with de novo AML, secondary AML, MDS-EB1, MDS-EB2 and T-AML/MDS were seen in 66%, 13%, 9%, 9% and 3%, respectively. TP53 mutation was found in 14 patients (10.6%), and prevalence of TP53 mutation in T-AML/MDS, secondary AML, de novo AML and MDS-EB patients were 50%, 17.6%, 9.2% and 8%, respectively. Three patients had double heterozygous TP53 mutation. Mutated TP53 was significantly detected in patients with monosomy and complex chromosome. Common TP53 mutation were R290C, T220C, A249S and V31I which V31I mutation was reported only in Taiwanese patients. Most variant allele frequency (VAF) of TP53 mutation in the study were greater than 40%. Three year-overall survival (OS) in the whole population was 22%, 3y-OS in AML and MDS-EB patients were 22% and 27%, respectively. In multivariate analysis, factors affecting OS in 132 AML/MDS patients was mutant TP53 (P= 0.023, HR= 1.20- 7.02), whereas, WBC count> 100,000/μL (P= 0.004, HR= 1.32- 4.16) and complex karyotype (P= 0.038, HR= 1.07- 9.78) were associated with shorter OS in AML patients. Discussion: In this study, the prevalence of TP53 mutation in de novo AML and MDS-EB patients were low but it had impact on survival. Patients with monosomy or complex karyotype had more frequent TP53 mutation.

scholarly journals Acute myeloid leukemia ontogeny is defined by distinct somatic mutations

Blood ◽  
2015 ◽  
Vol 125 (9) ◽  
pp. 1367-1376 ◽  
Author(s):  
R. Coleman Lindsley ◽  
Brenton G. Mar ◽  
Emanuele Mazzola ◽  
Peter V. Grauman ◽  
Sarah Shareef ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Somatic Mutations ◽  
De Novo ◽  
Clinical Heterogeneity ◽  
Secondary Aml ◽  
Key Points ◽  
De Novo Aml ◽  
Secondary Type ◽  
Acute Myeloid

Key Points The presence of a mutation in SRSF2, SF3B1, U2AF1, ZRSR2, ASXL1, EZH2, BCOR, or STAG2 is highly specific for secondary AML. Secondary-type mutations define an s-AML–like disease within t-AML and elderly de novo AML that underlies clinical heterogeneity.

scholarly journals De Novo and Secondary Acute Myeloid Leukemia, Real World Data on Outcomes from the French Nord-Pas-De-Calais Picardie Acute Myeloid Leukemia Observatory

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 4013-4013 ◽  
Author(s):  
Loïc Renaud ◽  
Olivier Nibourel ◽  
Celine Berthon ◽  
Christophe Roumier ◽  
Céline Rodriguez ◽  
...  
Keyword(s):  
Overall Survival ◽  
Acute Myeloid Leukemia ◽  
Supportive Care ◽  
Real World ◽  
Myeloid Leukemia ◽  
De Novo ◽  
Secondary Aml ◽  
Secondary Acute Myeloid Leukemia ◽  
De Novo Aml ◽  
Acute Myeloid

Abstract Background. Population-based registries may provide data complementary to that from clinical intervention studies. Registries with high coverage of the target population reduce the impact of selection on outcome and the subsequent problem with extrapolating data to nonstudied populations like secondary Acute Myeloid Leukemia (AML). Actually, secondary AML are frequently excluded from clinical trials so the registries constitute the only way to fine data for establishing recommendations for the management of these patients in the real world. Method. The French Nord-pas-de-calais Picardie AML observatory containing 1 582 AML patients diagnosed between 2000 and 2015. We compared 974 primary AML to 514 Secondary AML include AML arising from a pre-existing myelodysplastic (n=211), myeloproliferative (n=88) or myelodysplastic/myeloproliferative (n=57) disease and therapy related AML (t-AML) (n=158). Results. Median survival and 5 years overall survival were respectively 420 days [95%IC: 349-491] and 32% for patients with de novo AML; 157 days [95%IC: 118-196] and 7% for patients with secondary AML. 1101 patients were classified according to the MRC as favorable, intermediate and unfavorable, respectively 18(5.2%), 178(51.9%) and 147(42.9%) patients with secondary AML including 100(29.2%) complexes karyotypes and 117(15.4%), 468(61.7%) and 173(22.8%) patients with de novo AML including 121 (15.9%) complexes karyotypes. 987 patients were classified according to the ELN as favorable, intermediate-1, intermediate-2 and unfavorable for respectively 35(11.7%), 53(17.7%), 67(22.%) and 144(48.2%) patients with secondary AML and 219(31.8%), 167(24.%), 136(19.8%) and 166(24.1%) patients with de novo AML. The age at diagnosis was significantly different (p < 10-3) with a median of 72.6 years for secondary AML and 63.2 for de novo AML. 206 (40.4%) patients with secondary AML received demethylating agents versus 184 (19%) for de novo AML and 152(29%) received high dose chemotherapy (HDC) versus 619 (63.9%) patients with de novo AML. Best supportive care was the only treatment for 170 (17.5%) de novo AML and 164 (31.9%) secondary AML patients. For patients over than 60 years old, median survival and 5 years overall survival were respectively 182 days [95%IC: 136.5-127.4] and 12.9% for 559 patients with de novo AML; 128 days [95%IC: 95.0-161.0] and <4% for 413 patients with secondary AML. Conclusion. The poor prognosis of secondary and t- AML is confirmed by this registry study. Possible explanations for this worse outcome could be older age at diagnosis and increased frequency of complex karyotypes which lead to less intensive therapy or supportive care only. In this specific population, the choice of demethylating agent therapy was frequently made because of the weak efficacy of HDC and increased frequency of side effects in this vulnerable group. Disclosures No relevant conflicts of interest to declare.

scholarly journals Leukemic Stem Cell Phenotype Is Associated with Mutational Profile in Acute Myeloid Leukemia

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 3852-3852
Author(s):  
Ja Min Byun ◽  
Dong-Yeop Shin ◽  
Youngil Koh ◽  
Sung-Soo Yoon ◽  
Junshik Hong ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Stem Cell ◽  
Genomic Dna ◽  
Myeloid Leukemia ◽  
Research Funding ◽  
De Novo ◽  
Leukemic Stem Cell ◽  
Secondary Aml ◽  
De Novo Aml ◽  
Acute Myeloid

Background: Understanding leukemic stem cell (LSC) is important for acute myeloid leukemia (AML) treatment. As such, understanding the relationship between LSC and genetically defined sub-clones can, in turn, help to understand the heterogeneity of AML. However, to date, there are only a few reports specifically focusing on this topic. To this end, we conducted this study to (1) examine the phenotypic diversity of AML-LSC, (2) explore the association between AML-LSC phenotypes and gene mutations, and (3) investigate the prognostic implications of AML-LSCs. Methods: Mononuclear cells (MNCs) were isolated from the patient's bone marrow aspirates by ficoll gradient centrifugation and cryopreserved in serum-free medium. Stored cells were thawed to Iscove's Modified Dulbecco's Medium (IMDM) and washed with fluorescence-activated cell sorting (FACS) buffer [1% FBS, Dulbecco's Phosphate-Buffered Saline (DPBS)]. Cells were stained with following anti-human monoclonal antibodies: CD45-APC/cy7, CD34-APC, CD38-BV421, CD90-PE, CD123-PE/Cy7, CD45RA-PerCP/Cy5.5. Analyses were performed on a FACSCanto II (HTS) (BD Bioscience) and FlowJo V 10.0 (BD Bioscience) program. For sequencing, the DNA capture probes for 76 target genes were designed using the Agilent SureDesign web-based application. The target regions included protein coding exons with 10 bp intron flanking regions and hot spot regions of the 20 genes involved in recurrent translocations. DNA was extracted on a Chemagic 360 instrument (Perkin Elmer, Baesweiler, Germany). The genomic DNA was sheared using Covaris S220 focused‐ultrasonicator (Covaris, Woburn, MA). We used 50ng of total input genomic DNA. A library preparation was performed according to Agilent's SureSelectQXT Target Enrichment protocol. Paired-end 150-bp sequencing was using NextSeq 550 Dx platform (Illumina, San Diego, CA). Targeted sequencing raw data was obtained in FASTQ format. Results: In secondary AML patients, MPP-like LSC was significantly higher than de-novo AML (p=0.0037), and was higher in MPN-AML than in MDS-AML (p=0.0485). There was no correlation between age and LSC phenotype, though CD34+CD38- subpopulation was enriched in younger patients (<65 yrs). Mutations of KRAS and NRAS were frequently observed in MPP-like LSC dominant patients (3/14 and 4/14), TP53 and ASXL1 mutations in LMPP-like LSC dominant patients (4/12 and 4/12) , and CEBPA, DNMT3A and IDH1 (6/12, 4/12, and 3/12) mutations in GMP-like LSC dominant patients. Furthermore, as shown in Figure, KRAS mutation was significantly associated with the percentage of MPP-like LSC phenotype (p=0.0540), and TP53 mutation with the percentage of LMPP-like LSC phenotype (p=0.0276). When the patients were separated according to the combined risk including next generation sequencing data, the poorer the prognosis, the higher the LMPP-like LSC expression (p=0.0052). The importance of our study lies in that we showed for a given AML patients there is a dominant LSC phenotype and LSCs are associated with clinical outcomes, supporting the significance of cancer stem cell model for human AML. First of all, based on detailed characterization of the surface immunophenotype of AML LSCs we found that AML show evidence of a hierarchical cellular organization. We also recognized that the composition of LSC phenotypes is associated with AML phenotypes. For example, secondary AML patients showed higher fraction of MPP-like LSCs compared to de novo AML patients. In this regard, the higher expression of MPP-like LSCs could explain the poor response to standard treatments traditionally associated with secondary AML. Furthermore, the higher expression of MPP-like LSCs in post-MPN AML compared to post-MDS AML could explain the dismal prognosis associated with post-MPN AML, despite the relative indolent clinical course in their chronic phase and the presence of druggable target. Conclusion: In conclusion, our findings provide better insights into the characteristics and clinical implications of LSC. Although in a small scale, we provide evidence that specific LSC phenotypes are associated with certain mutations thus should be in the AML risk stratification process. Figure Disclosures Yoon: Janssen: Consultancy; Kyowa Hako Kirin: Research Funding; Genentech, Inc.: Research Funding; Yuhan Pharma: Research Funding; MSD: Consultancy; Amgen: Consultancy, Honoraria; Novartis: Consultancy, Honoraria.

Methylation of the RIZ1 Gene In Myelodysplastic Syndrome and Acute Myeloid Leukemia

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 5112-5112
Author(s):  
Naoki Mori ◽  
Kentaro Yoshinaga ◽  
Mari Ohwashi ◽  
Toshiaki Kondoh ◽  
Hanae Shimura ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Promoter Region ◽  
Myeloid Leukemia ◽  
De Novo ◽  
Methylation Status ◽  
Leukemia Cells ◽  
Pcr Analysis ◽  
Secondary Aml ◽  
De Novo Aml ◽  
Acute Myeloid

Abstract Abstract 5112 Inactivation of a tumor suppressor gene is often caused by a mutation, small deletion of one allele accompanied by loss of the second allele. Methylation in a promoter CpG of several tumor suppressor genes has recently been reported and has been associated with loss or decreased expression in many tumors. We previously reported frequent loss of heterozygosity on the short arm of chromosome 1 (1p) in the progression of myelodysplastic syndrome (MDS) to acute myeloid leukemia (AML). The retinoblastoma protein-interacting zinc finger gene RIZ maps to 1p36. Mouse gene knockout models show that RIZ1 inactivation can cause tumor susceptibility. Inactivation of the RIZ1 gene by promoter hypermethylation has been reported in breast, liver, and gastric carcinoma. Previous study showed altered expression of the RIZ1 gene in human leukemia. However, methylation status of the RIZ1 gene has not been well studied in hematological neoplasms. To determine the relevance of the RIZ1 methylation, we performed methylation specific-polymerase chain reaction (PCR) analysis on the RIZ1 gene in 34 patients with MDS and 17 with AML evolved from MDS (secondary AML) as well as 55 patients with de novo AML. The 34 MDS samples consisted of 13 refractory anemia (RA), 1 RA with ringed sideroblasts (RARS), 10 RA with excess of blasts (RAEB), 6 RAEB in transformation (RAEB-t), and 4 chronic myelomonocytic leukemia. The 55 de novo AML consisted of 1 M0, 12 M1, 17 M2, 7 M3, 8 M4, 7 M5, 1 M6, and 2 M7. Written informed consent was obtained from the patients. Methylation of the RIZ1 gene was detected in 17 of the 34 MDS (50%) and 22 of 72 de novo and secondary AML (31%) (p=0.053). Methylation was detected in 7 of 14 low risk MDS (50%) and 10 of 20 high risk MDS (50%). Patients with MDS were classified using the IPSS score. Frequency of methylation was not statistically different among IPSS subgroups (p=0.419). No statistical differences were observed between methylation and overall survival (3 years) or progression to AML. In AML patients, methylation was more frequent in secondary AML (11/17, 65%) than in de novo AML (11/55, 20%) (p=0.0005). To define the methylation status of the CpG in the RIZ1 promoter region, we performed bisulfite sequence in several samples with methylation. Bisulfite sequence analysis revealed methylation at many CpG sites in the promoter region. Expression of the RIZ1 gene was examined by quantitative real time reverse transcriptase-PCR analysis in 22 samples of MDS and AML. RIZ1 expression (mean) was not statistically different in secondary AML and de novo AML (2.026 vs. 1.900, p=0.815). RIZ1 expression (mean) was not statistically different in methylation-positive group and methylation-negative group (1.996 vs. 1.810, p=0.728). In comparison with expression of normal bone marrow cells, decreased RIZ1 expression was accompanied by methylation in 6 of 9 samples examined, while it was also observed in 7 of 13 without methylation. HL-60 myeloid leukemia cells with RIZ1 methylation were cultivated for 3 days in the presence of various concentrations of 5-Aza-dC. Treatment of the leukemia cells with 5 Aza-dC induced growth suppression with RIZ1 restoration. Our results suggest that the RIZ1 gene was inactivated in MDS and AML in part by methylation, whereas another mechanism of inactivation should be involved in others. Disclosures: No relevant conflicts of interest to declare.

Expression of mast cell tryptase by myeloblasts in a group of patients with acute myeloid leukemia

Blood ◽  
2001 ◽  
Vol 98 (7) ◽  
pp. 2200-2209 ◽  
Author(s):  
Wolfgang R. Sperr ◽  
John-Hendrik Jordan ◽  
Mehrdad Baghestanian ◽  
Hans-Peter Kiener ◽  
Puchit Samorapoompichit ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Messenger Rna ◽  
Myeloid Leukemia ◽  
De Novo ◽  
Elevated Serum ◽  
Leukemia Cell ◽  
Acute Leukemias ◽  
Secondary Aml ◽  
De Novo Aml ◽  
Acute Myeloid

α- and β-tryptase genes encode serine proteases that are abundantly expressed by mast cells. Under physiologic conditions other myeloid cells are virtually tryptase negative. However, tryptases are also expressed in several myeloid leukemia cell lines. In this study, serum total tryptase levels were determined in 150 patients with acute leukemias (de novo acute myeloid leukemia [AML], n = 108; secondary AML, n = 25; acute lymphoid leukemia [ALL], n = 17) by fluoroenzyme immunoassay. In healthy subjects (n = 30), tryptase levels ranged between 2.0 and 12.6 ng/mL. Elevated tryptase levels (&gt; 15) were detected in 42 (39%) of 108 patients with de novo AML and in 11 (44%) of 25 patients with secondary AML. No elevated tryptase levels were found in patients with ALL. In de novo AML, elevated tryptase levels were frequently detected in patients with French-American-British classification M0 (6 of 9), M2 (9 of 14), M3 (4 of 6), and M4eo (7 of 7), and less frequently in M1 (7 of 20), M4 (6 of 26), M5 (2 of 18), M6 (0 of 5), or M7 (1 of 3). The highest tryptase levels were found in M4eo. Immunohistochemical staining of bone marrow sections with anti-tryptase antibody as well as immunoelectron microscopy revealed tryptase expression in the cytoplasm of myeloblasts. As assessed by Northern blotting and reverse transcriptase–polymerase chain reaction, AML cells expressed α-tryptase messenger RNA (mRNA) but little or no β-tryptase mRNA. In AML patients with elevated serum tryptase before chemotherapy, who entered complete remission, tryptase levels returned to normal or near normal values. Blast cell persistence or regrowth was associated with a persistently elevated level or recurrent increase of tryptase. Together, tryptase is expressed in myeloblasts in a group of AML and may serve as a useful disease-related marker.

scholarly journals Vascular Endothelial Growth Factor, a Possible Paracrine Growth Factor in Human Acute Myeloid Leukemia

Blood ◽  
1997 ◽  
Vol 89 (6) ◽  
pp. 1870-1875 ◽  
Author(s):  
Walter Fiedler ◽  
Ullrich Graeven ◽  
Süleyman Ergün ◽  
Sandra Verago ◽  
Nerbil Kilic ◽  
...  
Keyword(s):  
Vascular Endothelial Growth Factor ◽  
Acute Myeloid Leukemia ◽  
Growth Factor ◽  
Myeloid Leukemia ◽  
De Novo ◽  
Vascular Endothelial ◽  
Secondary Aml ◽  
De Novo Aml ◽  
Endothelial Growth Factor ◽  
Acute Myeloid

Abstract Vascular endothelial growth factor (VEGF ) is a multifunctional cytokine involved in angiogenesis, inflammation, and wound healing. It is secreted by a variety of tumor cell lines, including hematopoietic lines. Therefore, we investigated expression of VEGF and its receptors on fresh leukemic blasts. VEGF-specific transcripts were detected by polymerase chain reaction (PCR) in 20 of 28 patients with de novo acute myeloid leukemia (AML) and in 3 of 5 patients with secondary AML. Using immunocytochemistry, we found VEGF protein in 2 leukemic cell lines and in 8 AML patients, in concordance with PCR results. Supernatants of fresh leukemic cells from 24 AML patients contained significantly more VEGF than supernatants from bone marrow cells of 9 normal donors or of CD34-enriched cells from 3 normal volunteer donors as determined by an enzyme-linked immunosorbent assay. VEGF possesses two high-affinity receptors, KDR and FLT1. Using a sensitive nested PCR assay, we detected expression of FLT1 in 10 of 20 patients with de novo AML and 3 of 5 patients with secondary AML. KDR was expressed in 4 of 22 patients with de novo AML and 1 of 4 with secondary AML. To study possible paracrine growth stimulation of AML blasts, endothelial cells from human umbilical cords were incubated with increasing concentrations of VEGF. A dose-dependent increase of granulocyte-macrophage colony-stimulating factor secretion from endothelial cells was identified.

Antileukemic activity of rapamycin in acute myeloid leukemia

Blood ◽  
2005 ◽  
Vol 105 (6) ◽  
pp. 2527-2534 ◽  
Author(s):  
Christian Récher ◽  
Odile Beyne-Rauzy ◽  
Cécile Demur ◽  
Gaëtan Chicanne ◽  
Cédric Dos Santos ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
De Novo ◽  
Mammalian Target Of Rapamycin ◽  
Cell Types ◽  
Mtor Inhibition ◽  
Growth And Survival ◽  
Clinical Responses ◽  
De Novo Aml ◽  
Acute Myeloid

AbstractThe mammalian target of rapamycin (mTOR) is a key regulator of growth and survival in many cell types. Its constitutive activation has been involved in the pathogenesis of various cancers. In this study, we show that mTOR inhibition by rapamycin strongly inhibits the growth of the most immature acute myeloid leukemia (AML) cell lines through blockade in G0/G1 phase of the cell cycle. Accordingly, 2 downstream effectors of mTOR, 4E-BP1 and p70S6K, are phosphorylated in a rapamycin-sensitive manner in a series of 23 AML cases. Interestingly, the mTOR inhibitor markedly impairs the clonogenic properties of fresh AML cells while sparing normal hematopoietic progenitors. Moreover, rapamycin induces significant clinical responses in 4 of 9 patients with either refractory/relapsed de novo AML or secondary AML. Overall, our data strongly suggest that mTOR is aberrantly regulated in most AML cells and that rapamycin and analogs, by targeting the clonogenic compartment of the leukemic clone, may be used as new compounds in AML therapy.

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