Influence of High Expression of p73 and p53 Proteins on Clinical Outcome in Acute Myeloid Leukemia Patients.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4306-4306
Author(s):  
Agnieszka Pluta ◽  
Piotr Smolewski ◽  
Agnieszka Wierzbowska ◽  
Barbara Cebula ◽  
Krzysztof Jamroziak ◽  
...  

Abstract Background: Prognostic significance of apoptosis-regulating proteins, especially p73, is not clearly determined in acute myeloid leukemia (AML). The p73 protein is a member of p53 family implicated in the regulation of cell cycle, apoptosis and development. Overexpression of p73 protein, with prevalence of short TAp73 isoforms, has recently been described in patients with AML. Aims: The main objective of this study was to verify whether expression of p73 and p53 proteins has a prognostic impact on response to induction chemotherapy and overall survival (OS) of adult patients with AML. Additionally, we aimed to correlate the expression of p73 and p53 proteins with spontaneous apoptosis of leukemic cells. Material and Methods: Intracellular expression of p73 protein in leukemic blasts isolated from bone marrow or peripheral blood was examined in 73 AML patients (59 de novo, 14 refractory/relapsed) of median age 54 years (range 28–78 years). In parallel, analysis of cell cycle in leukemic blasts was performed to assess the subG1 fraction as a marker of spontaneous apoptosis. The control constituted leukemic cells incubated with isotype antibodies. All measurements were performed using multi-colour flow cytometry. Protein expression was expressed by both percentage of positive cells and mean fluorescence intensity. Results: Fifty six patients received intensive induction chemotherapy. Twenty four (43%) patients achieved complete response (CR), 26 (46%) patients did not respond and 6 (11%) patients died in the early post-induction period. The median time of follow up reached 5.6 months (range 0.1–99 months). High expression of p73 showed a trend towards probability of CR achievement after induction regimen (p=0.08). Higher expression of p53 did not correlate with response to the treatment (p=0.28). In univariate analysis we found significantly better OS in patients less than 60 years old, with good or intermediate risk of kariotype and treated with intensive chemotherapy (p=0.00001; p=0.04; p=0.00001, respectively). Probability of better OS in AML patients with high p73 and p53 protein expression was p=0.1 and p=0.95, respectively. Simultaneous high expression of both p73 and p53 proteins on AML cell showed a trend toward longer OS (p=0.09). Moreover, a strong trend to better OS was observed in patients with high subG1 fraction. Importantly, high subG1 fraction correlated with high expression of p53 but not with p73 protein expression (p=0.03; p=0.15, respectively). Conclusions: These data indicate that p73 protein may be implicated in apoptosis of AML in response to chemotherapy, especially when p53 pathway is abrogated. Further studies are needed to establish exact role of p73 and p53 proteins in this process and its influence on OS of AML patients.

Blood ◽  
1993 ◽  
Vol 81 (11) ◽  
pp. 3091-3096 ◽  
Author(s):  
L Campos ◽  
JP Rouault ◽  
O Sabido ◽  
P Oriol ◽  
N Roubi ◽  
...  

The BCL-2 proto-oncogene encodes a mitochondrial protein that blocks programmed cell death. High amounts of bcl-2 protein are found not only in lymphoid malignancies, but also in normal tissues characterized by apoptotic cell death, including bone marrow. Using a monoclonal antibody to bcl-2 protein, we analyzed 82 samples of newly diagnosed acute myeloid leukemia. The number of bcl-2+ cells in each sample was heterogeneous (range, 0% to 95%), with a mean of 23%. The percentage of bcl-2+ cells was higher in M4 and M5 types, according to French- American-British classification, and in cases with high white blood cell counts. bcl-2 expression was also correlated with that of the stem cell marker CD34. In vitro survival of leukemic cells maintained in liquid culture in the absence of growth factors was significantly longer in cases with a high percentage of bcl-2+ cells. High expression of bcl-2 was associated with a low complete remission rate after intensive chemotherapy (29% in cases with 20% or more positive cells v 85% in cases with less than 20% positive cells, P < 10(-5)) and with a significantly shorter survival. In multivariate analysis, the percentage of bcl-2+ cells (or the blast survival in culture), age, and the percentage of CD34+ cells were independently associated with poor survival.


Blood ◽  
2003 ◽  
Vol 101 (8) ◽  
pp. 3142-3149 ◽  
Author(s):  
Yinghui Guan ◽  
Brigitte Gerhard ◽  
Donna E. Hogge

Abstract Although many acute myeloid leukemia (AML) colony-forming cells (CFCs) and long-term culture–initiating cells (LTC-ICs) directly isolated from patients are actively cycling, quiescent progenitors are present in most samples. In the current study,3H-thymidine (3H-Tdr) suicide assays demonstrated that most NOD/SCID mouse leukemia-initiating cells (NOD/SL-ICs) are quiescent in 6 of 7 AML samples. AML cells in G0, G1, and S/G2+M were isolated from 4 of these samples using Hoechst 33342/pyroninY staining and cell sorting. The progenitor content of each subpopulation was consistent with the 3H-Tdr suicide results, with NOD/SL-ICs found almost exclusively among G0 cells while the cycling status of AML CFCs and LTC-ICs was more heterogeneous. Interestingly, after 72 hours in serum-free culture with or without Steel factor (SF), Flt-3 ligand (FL), and interleukin-3 (IL-3), most G0 AML cells entered active cell cycle (percentage of AML cells remaining in G0 at 72 hours, 1.2% to 37%, and 0% to 7.6% in cultures without and with growth factors [GFs], respectively) while G0 cells from normal lineage-depleted bone marrow remained quiescent in the absence of GF. All 4 AML samples showed evidence of autocrine production of 2 or more of SF, FL, IL-3, and granulocyte-macrophage colony-stimulating factor (GM-CSF). In addition, 3 of 4 samples contained an internal tandem duplication of theFLT3 gene. In summary, quiescent leukemic cells, including NOD/SL-ICs, are present in most AML patients. Their spontaneous entry into active cell cycle in short-term culture might be explained by the deregulated GF signaling present in many AMLs.


Blood ◽  
1993 ◽  
Vol 81 (11) ◽  
pp. 3091-3096 ◽  
Author(s):  
L Campos ◽  
JP Rouault ◽  
O Sabido ◽  
P Oriol ◽  
N Roubi ◽  
...  

Abstract The BCL-2 proto-oncogene encodes a mitochondrial protein that blocks programmed cell death. High amounts of bcl-2 protein are found not only in lymphoid malignancies, but also in normal tissues characterized by apoptotic cell death, including bone marrow. Using a monoclonal antibody to bcl-2 protein, we analyzed 82 samples of newly diagnosed acute myeloid leukemia. The number of bcl-2+ cells in each sample was heterogeneous (range, 0% to 95%), with a mean of 23%. The percentage of bcl-2+ cells was higher in M4 and M5 types, according to French- American-British classification, and in cases with high white blood cell counts. bcl-2 expression was also correlated with that of the stem cell marker CD34. In vitro survival of leukemic cells maintained in liquid culture in the absence of growth factors was significantly longer in cases with a high percentage of bcl-2+ cells. High expression of bcl-2 was associated with a low complete remission rate after intensive chemotherapy (29% in cases with 20% or more positive cells v 85% in cases with less than 20% positive cells, P < 10(-5)) and with a significantly shorter survival. In multivariate analysis, the percentage of bcl-2+ cells (or the blast survival in culture), age, and the percentage of CD34+ cells were independently associated with poor survival.


2021 ◽  
Vol 11 ◽  
Author(s):  
Christian Récher

Recent advances in the description of the tumor microenvironment of acute myeloid leukemia, including the comprehensive analysis of the leukemic stem cell niche and clonal evolution, indicate that inflammation may play a major role in many aspects of acute myeloid leukemia (AML) such as disease progression, chemoresistance, and myelosuppression. Studies on the mechanisms of resistance to chemotherapy or tyrosine kinase inhibitors along with high-throughput drug screening have underpinned the potential role of glucocorticoids in this disease classically described as steroid-resistant in contrast to acute lymphoblastic leukemia. Moreover, some mutated oncogenes such as RUNX1, NPM1, or SRSF2 transcriptionally modulate cell state in a manner that primes leukemic cells for glucocorticoid sensitivity. In clinical practice, inflammatory markers such as serum ferritin or IL-6 have a strong prognostic impact and may directly affect disease progression, whereas interesting preliminary data suggested that dexamethasone may improve the outcome for AML patients with a high white blood cell count, which paves the way to develop prospective clinical trials that evaluate the role of glucocorticoids in AML.


Blood ◽  
1998 ◽  
Vol 91 (9) ◽  
pp. 3401-3413 ◽  
Author(s):  
S. Legras ◽  
U. Günthert ◽  
R. Stauder ◽  
F. Curt ◽  
S. Oliferenko ◽  
...  

CD44 is a ubiquitous cell-surface glycoprotein that displays many variant isoforms (CD44v) generated by alternative splicing of exons 2v to 10v. The expression of variant isoforms is highly restricted and correlated with specific processes, such as leukocyte activation and malignant transformation. We have herein studied CD44v expression in acute myeloid leukemia (AML) and, for comparison, in normal myelopoiesis. Protein expression of total CD44 and of CD44-3v, -6v, and -9v isoforms has been measured using specific monoclonal antibodies and flow cytometry. The composition of variant exon transcripts has been analyzed by semi-quantitative reverse transcriptase-polymerase chain reaction followed by Southern hybridization with exon-specific probes. Our data show that (1) CD44-6v isoforms are expressed on 12.0% ± 2.5% of normal CD34+ cells; this expression is sharply upregulated through monopoiesis and, inversely, downregulated during granulopoiesis. Also, CD44-3v and CD44-9v isoforms are detected on 10% and 14% of normal monocytes, respectively. (2) Sixty-nine from a total of 95 AML patients display a variable proportion (range, 5% to 80%) of CD44-6v+ leukemic cells. (3) A shorter overall survival characterizes the group of AML patients displaying more than 20% of CD44-6v+ leukemic cells (8 months v 18 months, P < .02). These data suggest, for the first time, that the protein expression of CD44-6v containing isoforms may serve as a new prognostic factor in AML.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 2585-2585
Author(s):  
Tzung-Chih Tang ◽  
Hung Chang ◽  
Chien-Feng Sun ◽  
Lee-Yung Shih ◽  
Po Dunn ◽  
...  

Abstract Abstract 2585 Background: Microenvironment of bone marrow (BM) plays an important role to support proliferation, renewal and differentiation of hematopoietic stem cells. Whether the stroma of BM affects leukemic cells with the same manner, or impacts on the prognosis in leukemia patients, has not been fully investigated. Previous studies have described that increased reticulin content in the BM is associated with poor outcome in patients with acute lymphoblastic leukemia, chronic myeloid leukemia and primary myelofibrosis, but there is no cohort study to determine the clinical correlation between degree of reticulin fibrosis of BM and acute myeloid leukemia (AML). To investigate prognostic impact of reticulin fibrosis on de novo AML, 881 patients diagnosed between Jun 1999 to Dec 2011 in Chang Gung Memorial Hospital and treated with anthracycline-containing induction chemotherapy were retrospectively reviewed. Patients and methods: According to the grading of reticulin content in the bone marrow, we categorized the 881 patients into four groups: A. BM easily aspirated without biopsy, n = 698; B. Reticulin grade 0, n = 99; C. Reticulin grade 1–2, n = 51; D. Reticulin grade 3–4, n = 33. The induction failure (IF) rate after treatment with induction chemotherapy, the recovery duration of absolute neutrophil count (ANC) greater than 0.5 × 109/L in patients who achieved the first complete remission, the overall survival (OS) and relapse-free survival (RFS) in four groups were analyzed. Based on the cytogenetic or molecular features, 648 of the patients were stratified into unfavorable, intermediate and favorable risk groups, and the clinical significance of reticulin fibrosis of BM were also examined for various risk groups. Results: Of the 881 patients, the patients in group D had a statistically higher IF rate (P = 0.0108) and longer ANC recovery duration (P = 0.0008). But the OS and RFS between four groups were not significantly different (P = 0.5146 and 0.3853, respectively). After risk stratified by cytogenetic and molecular analysis, increased reticulin content of BM (group C or D) had an adverse impact on OS in the intermediate and favorable risk groups (P = 0.006 and 0.0215, respectively). Conclusion: Reticulin content of BM influences the IF rate and myeloid recovery for the patients of de novo AML, and affects OS in patients with intermediate or favorable risk factors. Disclosures: No relevant conflicts of interest to declare.


Cancers ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 73 ◽  
Author(s):  
Annette K. Brenner ◽  
Elise Aasebø ◽  
Maria Hernandez-Valladares ◽  
Frode Selheim ◽  
Frode Berven ◽  
...  

Acute myeloid leukemia (AML) is an aggressive malignancy, which is highly heterogeneous with regard to chemosensitivity and biological features. The AML cell population is organized in a hierarchy that is reflected in the in vitro growth characteristics, with only a minority of cells being able to proliferate for more than two weeks. In this study, we investigated the ability of AML stem cells to survive and proliferate in suspension cultures in the presence of exogenous mediators but without supporting non-leukemic cells. We saw that a high number of maintained stem cells (i.e., a large number of clonogenic cells after five weeks of culture) was associated with decreased overall survival for patients receiving intensive chemotherapy; this prognostic impact was also detected in the multivariate/adjusted analysis. Furthermore, the patients with many clonogenic cells presented more frequently with mutations in transcription-related genes, and also showed a higher abundance of proteins involved in transcription at the time of diagnosis. In conclusion, the growth characteristics of the long-term proliferating leukemic stem cells seem to have an independent prognostic impact in human AML, and these characteristics appear to be reflected by the mutational landscape and the proteome of the patients at the time of diagnosis.


Blood ◽  
1990 ◽  
Vol 76 (11) ◽  
pp. 2191-2197 ◽  
Author(s):  
A Raza ◽  
HD Preisler ◽  
R Day ◽  
Z Yasin ◽  
M White ◽  
...  

Abstract Cell cycle characteristics including labeling indices (LI), duration of S-phase (Ts), and total cell cycle time (Tc) were determined in 54 standard-risk, newly diagnosed patients with acute myeloid leukemia following an infusion of bromodeoxyuridine. Remission induction therapy consisting of cytosine arabinoside and daunomycin was then administered to all patients, followed by three courses of consolidation to those who achieved complete remissions (CR). Older patients appeared to have more rapidly cycling cells (P = .003). No unique cell cycle characteristics were identified for patients who achieved remission versus those who had resistant disease. However, the pretherapy cell cycle characteristics were a strong prognosticator for remission duration. CR patients were divided into those whose leukemic cell Tc were above median (A) and below median (B). Among 14 B patients, median duration of response was 211 days, and all relapsed by day 600. Among 18 A patients, the median has not as yet been reached, with nine patients in continuous complete remission (log rank P = .007, Wilcoxon P = .04). We conclude that cell cycle characteristics of leukemic cells play a role in determining remission duration, perhaps because the leukemic cells of the former patients regrow slowly between courses of chemotherapy.


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