Genomic markers of midostaurin drug sensitivity in FLT3 mutated and FLT3 wild-type acute myeloid leukemia patients

Purpose To determine the efficacy and toxicity of the combination of sorafenib, cytarabine, and idarubicin in patients with acute myeloid leukemia (AML) younger than age 65 years. Patients and Methods In the phase I part of the study, 10 patients with relapsed AML were treated with escalating doses of sorafenib with chemotherapy to establish the feasibility of the combination. We then treated 51 patients (median age, 53 years; range, 18 to 65 years) who had previously untreated AML with cytarabine at 1.5 g/m2 by continuous intravenous (IV) infusion daily for 4 days (3 days if > 60 years of age), idarubicin at 12 mg/m2 IV daily for 3 days, and sorafenib at 400 mg orally twice daily for 7 days. Results Overall, 38 (75%) patients have achieved a complete remission (CR), including 14 (93%) of 15 patients with mutated FMS-like tyrosine kinase-3 (FLT3; the 15th patient had complete remission with incomplete platelet recovery [CRp]) and 24 (66%) of 36 patients with FLT3 wild-type (WT) disease (three additional FLT3-WT patients had CRp). FLT3-mutated patients were more likely to achieve a CR than FLT3-WT patients (P = .033). With a median follow-up of 54 weeks (range, 8 to 87 weeks), the probability of survival at 1 year is 74%. Among the FLT3-mutated patients, 10 have relapsed and five remain in CR with a median follow-up of 62 weeks (range, 10 to 76 weeks). Plasma inhibitory assay demonstrated an on-target effect on FLT3 kinase activity. Conclusion Sorafenib can be safely combined with chemotherapy, produces a high CR rate in FLT3-mutated patients, and inhibits FLT3 signaling.

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HOXA11 Regulates Chemoresistance By Modulating p53 Gene Expression in Acute Myeloid Leukemia

Blood ◽

10.1182/blood-2019-127542 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 5182-5182

Author(s):

Xutao Guo ◽

Bowen Yan ◽

Yi Qiu

Keyword(s):

Gene Expression ◽

Cell Proliferation ◽

Myeloid Leukemia ◽

Drug Sensitivity ◽

P53 Gene ◽

Resistant Cell ◽

Wild Type ◽

P53 Expression ◽

Acute Myeloid ◽

Resistant Cells

Acute myeloid leukemia (AML) exhibits large intrinsic variation in drug responsiveness due to its inherent heterogeneity. Therefore, it is important to understand the resistant mechanism in order to improve the treatment. In our previously study, the OCI-AML2-resistant cell lines were established to resist cytarabine (Ara-C) in the concentration of 50 µM (OCI-AML2 R50). The RNA-seq results showed that many genes changed in the resistant cells compared to wild type OCI-AML2 cells. One of the most remarkably decreased gene in resistant cells was HOXA11 (Homeobox A11). It is the part of the A cluster on chromosome 7 and encodes a DNA-binding transcription factor which regulates gene expression, morphogenesis, and differentiation. In this study, we have evaluated the importance of HOXA11 in AML chemoresistance. We found that knockdown of HOXA11 repressed the WT OCI-AML2 cell proliferation and increased the population of cells expressing CD123 and CD47 LSC (Leukemia stem cell) markers and enhanced the resistance to Ara-C in vitro, while overexpression of HOXA11 showed the reverse effect. These results support the idea that HOXA11 promotes drug sensitivity and apoptosis in AML. However, the result also showed that overexpression of HOXA11 repressed the OCI-AML2 R50 cell proliferation and enhanced the resistance. Therefore, HOXA11 plays opposite role in sensitive cells and resistant cells. We further investigated the mechanism for these effects. We found that knockdown of HOXA11 decreased the p53 gene expression and overexpression of HOXA11 increased the expression of p53 in OCI-AML2 and R50 cells. Further, in OCI-AML2 R50 cells p53 has a hotspot mutation in DNA binding site and studies have shown that p53 mutation enhance cancer cell survival and chemoresistance. Therefore, our study shows dual roles for HOXA11 in cell survival. In p53 wild type parental AML2 cells, HOXA11 induces wild type p53 expression to enhance drug sensitivity while in resistant cell, HOXA11 promotes mutant p53 expression and enhances the resistance of chemotherapy. Disclosures No relevant conflicts of interest to declare.

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High incidence of alternatively spliced forms of deoxycytidine kinase in patients with resistant acute myeloid leukemia

Blood ◽

10.1182/blood.v96.4.1517.h8001517_1517_1524 ◽

2000 ◽

Vol 96 (4) ◽

pp. 1517-1524 ◽

Cited By ~ 1

Author(s):

Marjan J. T. Veuger ◽

M. Willy Honders ◽

Jim E. Landegent ◽

Roel Willemze ◽

Renée M. Y. Barge

Keyword(s):

T Cells ◽

Acute Myeloid Leukemia ◽

Messenger Rna ◽

Myeloid Leukemia ◽

Deoxycytidine Kinase ◽

Wild Type ◽

Healthy Donors ◽

Alternatively Spliced ◽

Acute Myeloid

Deficiency of functional deoxycytidine kinase (dCK) is a common characteristic for in vitro resistance to cytarabine (AraC). To investigate whether dCK is also a target for induction of AraC resistance in patients with acute myeloid leukemia (AML), we determined dCK messenger RNA (mRNA) expression in (purified) leukemic blasts and phytohemagglutinin-stimulated T cells (PHA T cells) from patients with chemotherapy-sensitive and chemotherapy-resistant AML. In control samples from healthy donors (PHA T cells and bone marrow), only wild-type dCK complementary DNA (cDNA) was amplified. Also, in (purified) leukemic blasts from patients with sensitive AML, only wild-type dCK cDNAs were observed. These cDNAs coded for active dCK proteins in vitro. However, in 7 of 12 (purified) leukemic blast samples from patients with resistant AML, additional polymerase chain reaction fragments with a deletion of exon 5, exons 3 to 4, exons 3 to 6, or exons 2 to 6 were detected in coexpression with wild-type dCK. Deletion of exons 3 to 6 was also identified in 6 of 12 PHA T cells generated from the patients with resistant AML. The deleted dCK mRNAs were formed by alternative splicing and did code for inactive dCK proteins in vitro. These findings suggest that the presence of inactive, alternatively spliced dCK mRNA transcripts in resistant AML blasts may contribute to the process of AraC resistance in patients with AML.

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Superior anti-tumor activity of the MDM2 antagonist idasanutlin and the Bcl-2 inhibitor venetoclax in p53 wild-type acute myeloid leukemia models

Journal of Hematology & Oncology ◽

10.1186/s13045-016-0280-3 ◽

2016 ◽

Vol 9 (1) ◽

Cited By ~ 41

Author(s):

Christian Lehmann ◽

Thomas Friess ◽

Fabian Birzele ◽

Anna Kiialainen ◽

Markus Dangl

Keyword(s):

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Wild Type ◽

Mdm2 Antagonist ◽

Anti Tumor Activity ◽

Acute Myeloid

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Detection of the JAK2V617F Mutation in Myeloproliferative Disorders by Melting Curve Analysis Using the LightCycler System

Archives of Pathology & Laboratory Medicine ◽

10.5858/2006-130-997-dotjmi ◽

2006 ◽

Vol 130 (7) ◽

pp. 997-1003

Author(s):

Randall J. Olsen ◽

Zhouwen Tang ◽

Daniel H. Farkas ◽

David W. Bernard ◽

Youli Zu ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

De Novo ◽

Clinical Laboratory ◽

Melting Curve ◽

Myeloproliferative Disorder ◽

Curve Analysis ◽

Melting Curve Analysis ◽

Wild Type ◽

Acute Myeloid

Abstract Context.—A specific mutation, JAK2V617F, was recently recognized as having diagnostic value for myeloproliferative disorders. No practical assay is currently available for routine use in a clinical laboratory. Objective.—We report the development of a real-time polymerase chain reaction melting curve analysis assay that is appropriate for molecular diagnostics testing. Design.—Specific primers and fluorescence resonance energy transfer probes were designed, and patients with a previously diagnosed myeloproliferative disorder, de novo acute myeloid leukemia, or reactive condition were selected. The DNA was extracted from fresh and archived peripheral blood and bone marrow specimens, and real-time polymerase chain reaction melting curve analysis was performed on the LightCycler platform (Roche Applied Science, Indianapolis, Ind). Results.—The JAK2 region was successfully amplified, and wild-type amplicons were reproducibly discriminated from JAK2V617F amplicons. Titration studies using homozygous wild-type and mutant cell lines showed the relative areas under a melting curve were proportional to allele proportion, and the assay reliably detected one mutant in 20 total cells. JAK2V617F was identified in patients previously diagnosed with a myeloproliferative disorder or acute myeloid leukemia transformed from myeloproliferative disorder, whereas a wild-type genotype was identified in patients with reactive conditions or de novo acute myeloid leukemia. Conclusions.—These findings demonstrate the suitability of this assay for identifying JAK2V617F in a clinical laboratory setting. Furthermore, the semiquantitative detection of JAK2V617F in archived specimens provides a new tool for studying the prognostic significance of this mutation.

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Preferential transcription of the mutated allele in NPM1 mutated acute myeloid leukaemia

Scientific Reports ◽

10.1038/s41598-020-73782-x ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

G. D. Bailey ◽

L. Doolan ◽

A. Baskar ◽

L. C. Smith ◽

C. H. Seedhouse

Keyword(s):

Acute Myeloid Leukemia ◽

Acute Myeloid Leukaemia ◽

Myeloid Leukaemia ◽

Myeloid Leukemia ◽

Splice Variants ◽

Wild Type ◽

Significant Bias ◽

Acute Myeloid

Abstract Nucleophosmin is commonly both over-expressed and mutated in acute myeloid leukemia (AML). NPM1 mutations are always heterozygous. In addition, NPM1 has a number of different splice variants with the major variant encoded by exons 1–9 and 11–12 (NPM1.1). Further variants include NPM1.2 which lacks exons 8 and 10 and NPM1.3 which comprises exons 1–10 (and so lacks the region of sequence mutated in AML). In this study we quantified the expression of these three variants in 108 AML patient samples with and without NPM1 mutations and also assessed the level of expression from the wild-type and mutant alleles in variants NPM1.1 and NPM1.2. The results show that NPM1.1 is the most commonly expressed variant, however transcripts from wild-type and mutated alleles do not occur at equal levels, with a significant bias toward the mutated allele. Considering the involvement of mutant nucleophosmin in the progression and maintenance of AML, a bias towards mutated transcripts could have a significant impact on disease maintenance.

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PF225 AZACITIDINE (AZA) ENHANCES ANTILEUKEMIC ACTIVITY OF THE MDM2 INHIBITOR MILADEMETAN IN TP53 WILD-TYPE ACUTE MYELOID LEUKEMIA (AML)

HemaSphere ◽

10.1097/01.hs9.0000559116.40081.dc ◽

2019 ◽

Vol 3 (S1) ◽

pp. 65 ◽

Cited By ~ 2

Author(s):

S. Noguchi ◽

T. Seki ◽

N. Adachi ◽

H. Sumi ◽

R. Nakano ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Wild Type ◽

Antileukemic Activity ◽

Mdm2 Inhibitor ◽

Acute Myeloid

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High incidence of alternatively spliced forms of deoxycytidine kinase in patients with resistant acute myeloid leukemia

Blood ◽

10.1182/blood.v96.4.1517 ◽

2000 ◽

Vol 96 (4) ◽

pp. 1517-1524 ◽

Cited By ~ 57

Author(s):

Marjan J. T. Veuger ◽

M. Willy Honders ◽

Jim E. Landegent ◽

Roel Willemze ◽

Renée M. Y. Barge

Keyword(s):

T Cells ◽

Acute Myeloid Leukemia ◽

Messenger Rna ◽

Myeloid Leukemia ◽

Deoxycytidine Kinase ◽

Wild Type ◽

Healthy Donors ◽

Alternatively Spliced ◽

Acute Myeloid

Abstract Deficiency of functional deoxycytidine kinase (dCK) is a common characteristic for in vitro resistance to cytarabine (AraC). To investigate whether dCK is also a target for induction of AraC resistance in patients with acute myeloid leukemia (AML), we determined dCK messenger RNA (mRNA) expression in (purified) leukemic blasts and phytohemagglutinin-stimulated T cells (PHA T cells) from patients with chemotherapy-sensitive and chemotherapy-resistant AML. In control samples from healthy donors (PHA T cells and bone marrow), only wild-type dCK complementary DNA (cDNA) was amplified. Also, in (purified) leukemic blasts from patients with sensitive AML, only wild-type dCK cDNAs were observed. These cDNAs coded for active dCK proteins in vitro. However, in 7 of 12 (purified) leukemic blast samples from patients with resistant AML, additional polymerase chain reaction fragments with a deletion of exon 5, exons 3 to 4, exons 3 to 6, or exons 2 to 6 were detected in coexpression with wild-type dCK. Deletion of exons 3 to 6 was also identified in 6 of 12 PHA T cells generated from the patients with resistant AML. The deleted dCK mRNAs were formed by alternative splicing and did code for inactive dCK proteins in vitro. These findings suggest that the presence of inactive, alternatively spliced dCK mRNA transcripts in resistant AML blasts may contribute to the process of AraC resistance in patients with AML.

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