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51
result(s) for
"Kolitz, Jonathan E."
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Expression and prognostic impact of lncRNAs in acute myeloid leukemia
by
John C. Byrd
,
Clara D. Bloomfield
,
Carlo M. Croce
in
Apoptosis
,
Biological Sciences
,
biomarkers
2014
Long noncoding RNAs (lncRNAs) are transcripts longer than 200 nucleotides, located within the intergenic stretches or overlapping antisense transcripts of protein coding genes. LncRNAs are involved in numerous biological roles including imprinting, epigenetic regulation, apoptosis, and cell cycle. To determine whether lncRNAs are associated with clinical features and recurrent mutations in older patients (aged ≥60 y) with cytogenetically normal (CN) acute myeloid leukemia (AML), we evaluated lncRNA expression in 148 untreated older CN-AML cases using a custom microarray platform. An independent set of 71 untreated older patients with CN-AML was used to validate the outcome scores using RNA sequencing. Distinctive lncRNA profiles were found associated with selected mutations, such as internal tandem duplications in the FLT3 gene ( FLT3 -ITD) and mutations in the NPM1 , CEBPA , IDH2 , ASXL1 , and RUNX1 genes. Using the lncRNAs most associated with event-free survival in a training cohort of 148 older patients with CN-AML, we derived a lncRNA score composed of 48 lncRNAs. Patients with an unfavorable compared with favorable lncRNA score had a lower complete response (CR) rate [ P < 0.001, odds ratio = 0.14, 54% vs. 89%], shorter disease-free survival (DFS) [ P < 0.001, hazard ratio (HR) = 2.88] and overall survival (OS) ( P < 0.001, HR = 2.95). The validation set analyses confirmed these results (CR, P = 0.03; DFS, P = 0.009; OS, P = 0.009). Multivariable analyses for CR, DFS, and OS identified the lncRNA score as an independent marker for outcome. In conclusion, lncRNA expression in AML is closely associated with recurrent mutations. A small subset of lncRNAs is correlated strongly with treatment response and survival.
Significance Long noncoding RNAs (lncRNAs) are involved in numerous biological roles including epigenetic regulation, apoptosis, and cell cycle. Whereas lncRNAs contribute to epigenetic gene regulation, metastasis, and prognosis in solid tumors, their role in acute myeloid leukemia (AML) has not been hitherto reported. Here, we show that lncRNA expression profiles are associated with recurrent mutations, clinical features, and outcome in AML. A fraction of these lncRNAs may have a functional role in leukemogenesis. Furthermore, lncRNAs could be used as biomarkers for outcome in AML. The identification of patients likely to achieve complete remission with standard therapy alone, based on lncRNA expression, is a significant advance potentially sparing such patients from other toxicities and focusing investigational approaches on postremission studies.
Journal Article
NF1 mutations are recurrent in adult acute myeloid leukemia and confer poor outcome
by
Kolitz, Jonathan E
,
Walker, Christopher J
,
Byrd, John C
in
Acute myeloid leukemia
,
Adults
,
Amino acids
2018
Targeted mutation assessment of 81 genes in 1021 adults with de novo acute myeloid leukemia (AML) identified recurrent mutations in the neurofibromin 1 (NF1) gene in 52 (5.1%) patients, including 36 (5.2%) younger and 16 (4.8%) older patients, which suggests NF1 belongs to the 20 most frequently mutated genes in adult AML. NF1 mutations were found throughout the gene, and comprised missense, frameshift, and nonsense mutations. One mutation hotspot, at amino acid threonine 676 (Thr676), was found in 27% of AML patients with NF1 mutations. NF1-mutated patients belonged more often to the adverse European LeukemiaNet (ELN) risk category than NF1 wild-type patients. Among patients aged <60 years, the presence of NF1 Thr676 mutations was associated with lower complete remission (CR) rates (P = 0.04) and shorter overall survival (OS; P = 0.01), as was the presence of any NF1 mutation in patients in the adverse ELN risk category (CR, P = 0.05; OS, P < 0.001). CR rates were also lower in NF1-mutated patients aged ≥60 years compared with NF1 wild-type patients (P = 0.001). In summary, our findings provide novel insights into the frequency of NF1 mutations in AML, and are suggestive of an adverse prognostic impact in patients treated with standard chemotherapy.
Journal Article
MicroRNA Expression in Cytogenetically Normal Acute Myeloid Leukemia
by
Kolitz, Jonathan E
,
Whitman, Susan P
,
Paschka, Peter
in
Adult
,
Analysis of Variance
,
Biological and medical sciences
2008
This study outlines the development of a microRNA signature in patients with cytogenetically normal acute myeloid leukemia (AML) with high-risk molecular features. This type of AML constitutes approximately 65% of cases of cytogenetically normal AML and one third of all AML cases involving patients under the age of 60 years. The microRNA signature correlated not only with the clinical outcome but also with the expression of genes encoding proteins of the innate immune system.
This study outlines the development of a microRNA signature in patients with cytogenetically normal AML with high-risk molecular features. The microRNA signature correlated not only with the clinical outcome but also with the expression of genes encoding proteins of the innate immune system.
In almost half of patients with acute myeloid leukemia (AML), no cytogenetic abnormality is detectable in the leukemic cells. Such patients are in an intermediate-risk prognostic category,
1
but among them are subgroups of patients who have molecular markers associated with either a favorable prognosis or an unfavorable prognosis.
2
Gene-expression profiling can also identify subgroups of patients who have cytogenetically normal AML with different outcomes.
3
–
5
Patients with internal tandem duplication in the fms-related tyrosine kinase 3 gene (
FLT3
-ITD) and those without
FLT3
-ITD but with the wild-type nucleophosmin (
NPM1
) gene are in a high-risk group, whereas . . .
Journal Article
In vivo measurements document the dynamic cellular kinetics of chronic lymphocytic leukemia B cells
by
Messmer, Bradley T.
,
Koduru, Prasad
,
Hellerstein, Marc K.
in
Aged
,
B-Lymphocytes - cytology
,
B-Lymphocytes - metabolism
2005
Due to its relatively slow clinical progression, B cell chronic lymphocytic leukemia (B-CLL) is classically described as a disease of accumulation rather than proliferation. However, evidence for various forms of clonal evolution suggests that B-CLL clones may be more dynamic than previously assumed. We used a nonradioactive, stable isotopic labeling method to measure B-CLL cell kinetics in vivo. Nineteen patients drank an aliquot of deuterated water (2H2O) daily for 84 days, and 2H incorporation into the deoxyribose moiety of DNA of newly divided B-CLL cells was measured by gas chromatography/mass spectrometry, during and after the labeling period. Birth rates were calculated from the kinetic profiles. Death rates were defined as the difference between calculated birth and growth rates. These analyses demonstrated that the leukemic cells of each patient had definable and often substantial birth rates, varying from 0.1% to greater than 1.0% of the entire clone per day. Those patients with birth rates greater than 0.35% per day were much more likely to exhibit active or to develop progressive disease than those with lower birth rates Thus, B-CLL is not a static disease that results simply from accumulation of long-lived lymphocytes. Rather, it is a dynamic process composed also of cells that proliferate and die, often at appreciable levels. The extent to which this turnover occurs has not been previously appreciated. A correlation between birth rates and disease activity and progression appears to exist, which may help identify patients at risk for worsening disease in advance of clinical deterioration.
Journal Article
Conventional and non-conventional antigen-binding sites promote the development and function of chronic lymphocytic leukemia stereotyped subset #4 clones
by
Stamatopoulos, Kostas
,
Iatrou, Anastasia
,
Degano, Massimo
in
Affinity
,
antigen
,
antigen binding
2025
Immunoglobulins (IGs) made by chronic lymphocytic leukemia (CLL) B cells are unique in that they bind themselves (homo-dimerize). This interaction leads to signal transduction with functional consequences that depend on the affinity of homo-dimerization. We have studied the antigen-binding properties of the IGs from a subset of patients with CLL (Subset #4) that homo-dimerize at high affinity. Previously, we had found that subset #4 IGs bound viable lymphocytes. Our new studies, probing an array of >8,000 antigens, indicate that these IGs also bind influenza virus. Because of the IGs high-affinity homo-dimerization, we asked if the defined foreign- and self-antigenic interactions were mediated by conventional B-cell receptor (BCR) domains or a non-conventional receptor created by homo-dimerization. The studies indicated the latter since abrogation of homo-dimerization eliminated binding to influenza virus and its hemagglutinin and to viable lymphocytes. Using these findings, we modeled a developmental path whereby a naive IgM + B cell with subset #4 heavy and light chain variable domains used the conventional BCR to interact with auto- and foreign antigens and acquire homo-dimerization capacity to create the non-conventional antigen-receptor when transitioning to a leukemic cell. Future studies will determine if this process is an idiosyncratic occurrence or a physiologic principle.
Journal Article
Prognostic and biological significance of the proangiogenic factor EGFL7 in acute myeloid leukemia
by
Karunasiri, Malith
,
Burke, Matthew H.
,
Ozer, Hatice Gulcin
in
Aberration
,
Acute myeloid leukemia
,
Adult
2017
Epithelial growth factor-like 7 (EGFL7) is a protein that is secreted by endothelial cells and plays an important role in angiogenesis. Although EGFL7 is aberrantly overexpressed in solid tumors, its role in leukemia has not been evaluated. Here, we report that levels of both EGFL7 mRNA and EGFL7 protein are increased in blasts of patients with acute myeloid leukemia (AML) compared with normal bone marrow cells. High EGFL7 mRNA expression associates with lower complete remission rates, and shorter event-free and overall survival in older (age ≥60 y) and younger (age <60 y) patients with cytogenetically normal AML. We further show that AML blasts secrete EGFL7 protein and that higher levels of EGFL7 protein are found in the sera from AML patients than in sera from healthy controls. Treatment of patient AML blasts with recombinant EGFL7 in vitro leads to increases in leukemic blast cell growth and levels of phosphorylated AKT. EGFL7 blockade with an anti-EGFL7 antibody reduced the growth potential and viability of AML cells. Our findings demonstrate that increased EGFL7 expression and secretion is an autocrine mechanism supporting growth of leukemic blasts in patients with AML.
Journal Article
A Detailed Analysis of Parameters Supporting the Engraftment and Growth of Chronic Lymphocytic Leukemia Cells in Immune-Deficient Mice
2021
Patient-derived xenograft models of chronic lymphocytic leukemia (CLL) can be created using highly immunodeficient animals, allowing analysis of primary tumor cells in an in vivo setting. However, unlike many other tumors, CLL B lymphocytes do not reproducibly grow in xenografts without manipulation, proliferating only when there is concomitant expansion of T cells. Here we show that in vitro pre-activation of CLL-derived T lymphocytes allows for a reliable and robust system for primary CLL cell growth within a fully autologous system that uses small numbers of cells and does not require pre-conditioning. In this system, growth of normal T and leukemic B cells follows four distinct temporal phases, each with characteristic blood and tissue findings. Phase 1 constitutes a period during which resting CLL B cells predominate, with cells aggregating at perivascular areas most often in the spleen. In Phase 2, T cells expand and provide T-cell help to promote B-cell division and expansion. Growth of CLL B and T cells persists in Phase 3, although some leukemic B cells undergo differentiation to more mature B-lineage cells (plasmablasts and plasma cells). By Phase 4, CLL B cells are for the most part lost with only T cells remaining. The required B-T cell interactions are not dependent on other human hematopoietic cells nor on murine macrophages or follicular dendritic cells, which appear to be relatively excluded from the perivascular lymphoid aggregates. Notably, the growth kinetics and degree of anatomic localization of CLL B and T cells is significantly influenced by intravenous versus intraperitoneal administration. Importantly, B cells delivered intraperitoneally either remain within the peritoneal cavity in a quiescent state, despite the presence of dividing T cells, or migrate to lymphoid tissues where they actively divide; this dichotomy mimics the human condition in that cells in primary lymphoid tissues and the blood are predominately resting, whereas those in secondary lymphoid tissues proliferate. Finally, the utility of this approach is illustrated by documenting the effects of a bispecific antibody reactive with B and T cells. Collectively, this model represents a powerful tool to evaluate CLL biology and novel therapeutics in vivo .
Journal Article
A precision medicine classification for treatment of acute myeloid leukemia in older patients
2021
Background
Older patients (≥ 60 years) with acute myeloid leukemia (AML) often have multiple, sequentially acquired, somatic mutations that drive leukemogenesis and are associated with poor outcome. Beat AML is a Leukemia and Lymphoma Society-sponsored, multicenter umbrella study that algorithmically segregates AML patients based upon cytogenetic and dominant molecular abnormalities (variant allele frequencies (VAF) ≥ 0.2) into different cohorts to select for targeted therapies. During the conception of the Beat AML design, a historical dataset was needed to help in the design of the genomic algorithm for patient assignment and serve as the basis for the statistical design of individual genomic treatment substudies for the Beat AML study.
Methods
We classified 563 newly diagnosed older AML patients treated with standard intensive chemotherapy on trials conducted by Cancer and Leukemia Group B based on the same genomic algorithm and assessed clinical outcomes.
Results
Our classification identified core-binding factor and
NPM1
-mutated/
FLT3
-ITD-negative groups as having the best outcomes, with 30-day early death (ED) rates of 0 and 20%, respectively, and median overall survival (OS) of > 1 year and 3-year OS rates of ≥ 20%. All other genomic groups had ED rates of 17–42%, median OS ≤ 1 year and 3-year OS rates of ≤ 15%.
Conclusions
By classifying patients through this genomic algorithm, outcomes were poor and not unexpected from a non-algorithmic, non-dominant VAF approach. The exception is 30-day ED rate typically is not available for intensive induction for individual genomic groups and therefore difficult to compare outcomes with targeted therapeutics. This Alliance data supported the use of this algorithm for patient assignment at the initiation of the Beat AML study. This outcome data was also used for statistical design for Beat AML substudies for individual genomic groups to determine goals for improvement from intensive induction and hopefully lead to more rapid approval of new therapies.
Trial registration
ClinicalTrials.gov Identifiers: NCT00048958 (CALGB 8461), NCT00900224 (CALGB 20202), NCT00003190 (CALGB 9720), NCT00085124 (CALGB 10201), NCT00742625 (CALGB 10502), NCT01420926 (CALGB 11002), NCT00039377 (CALGB 10801), and NCT01253070 (CALGB 11001).
Journal Article
Precision oncology in AML: validation of the prognostic value of the knowledge bank approach and suggestions for improvement
by
Powell, Bayard L.
,
Bill, Marius
,
Carroll, Andrew J.
in
Acute myeloid leukemia
,
Adults
,
Algorithms
2021
Recently, a novel knowledge bank (KB) approach to predict outcomes of individual patients with acute myeloid leukemia (AML) was developed using unbiased machine learning. To validate its prognostic value, we analyzed 1612 adults with de novo AML treated on Cancer and Leukemia Group B front-line trials who had pretreatment clinical, cytogenetics, and mutation data on 81 leukemia/cancer-associated genes available. We used receiver operating characteristic (ROC) curves and the area under the curve (AUC) to evaluate the predictive values of the KB algorithm and other risk classifications. The KB algorithm predicted 3-year overall survival (OS) probability in the entire patient cohort (AUC
KB
= 0.799), and both younger (< 60 years) (AUC
KB
= 0.747) and older patients (AUC
KB
= 0.770). The KB algorithm predicted non-remission death (AUC
KB
= 0.860) well but was less accurate in predicting relapse death (AUC
KB
= 0.695) and death in first complete remission (AUC
KB
= 0.603). The KB algorithm’s 3-year OS predictive value was higher than that of the 2017 European LeukemiaNet (ELN) classification (AUC
2017ELN
= 0.707,
p
< 0.001) and 2010 ELN classification (AUC
2010ELN
= 0.721,
p
< 0.001) but did not differ significantly from that of the 17-gene stemness score (AUC
17-gene
= 0.732,
p
= 0.10). Analysis of additional cytogenetic and molecular markers not included in the KB algorithm revealed that taking into account atypical complex karyotype, infrequent recurrent balanced chromosome rearrangements and mutational status of the
SAMHD1
,
AXL
and
NOTCH1
genes may improve the KB algorithm. We conclude that the KB algorithm has a high predictive value that is higher than those of the 2017 and 2010 ELN classifications. Inclusion of additional genetic features might refine the KB algorithm.
Journal Article