Detection and Treatment of Molecular Relapse in Acute Myeloid Leukemia with RUNX1, CBFB or MLL Gene Translocations. Frequent Quantitative Monitoring of Molecular Markers in Different Compartments and Correlation with WT1 Gene Expression.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4356-4356
Author(s):  
Michael Doubek ◽  
Ivo Palasek ◽  
Zdenek Pospisil ◽  
Sona Struncova ◽  
Dana Dvorakova ◽  
...  
Keyword(s):  
Residual Disease ◽  
Subsequent Development ◽  
Fold Increase ◽  
Fusion Transcript ◽  
Clinical Relapse ◽  
Wt1 Gene ◽  
Fusion Transcripts ◽  
Mll Gene ◽  
Quantitative Monitoring ◽  
Acute Myeloid

Abstract Background. It seems that the population of leukemia stem cells (LSCs) have fundamental importance in the origin and maintenance of the acute myeloid leukaemia (AML). Eradication of LSCs is a new goal of AML therapy. We hypothesized, that by monitoring of minimal residual disease (MRD) and its dynamics in different compartments (peripheral blood, PB; bone marrow, BM; sorted CD34+ BM cells; and CD34- BM cells) it would be possible to find some patterns reliably predicting clinical relapse. Aims. To find which compartment is the best for MRD monitoring and whether it would be possible to treat the disease in the phase of molecular relapse in order to prevent the hematological relapse. Methods. MRD monitoring, in average once or twice per month, was performed in all phases of treatment, and was done even more frequently in the cases of unstable MRD. RQ PCR for fusion transcripts (CBFB/MYH11, RUNX1(AML1)/ETO or fusion transcripts of MLL gene) and WT1 gene was used. Molecular relapse was defined as reappearance of the fusion transcript detection or its 10-fold increase, repeatedly detected. Some patients with already known MRD dynamics and high probability of imminent hematological relapse were treated at the time of molecular relapse. Results. In 67 AML patients and 6 healthy volunteers, 2352 BM or PB samples were examined, including 265 samples from CD34+ BM cells. Follow up was 31–287 weeks (median: 113 w). The correlation between the fusion transcripts levels in BM and PB was excellent (r=0,9676). The correlation between WT1 PB and BM levels was far less satisfactory. Since the WT1values did not mostly reach zero values even if the level of fusion transcript was 0, we wanted to find some “normal” value for WT1. Using the ROC curves, however, we were not able to find any WT1 level being a confidential marker of molecular remission in either compartment (PB, BM, CD34− or CD34+). In relapsed patients, the time from molecular to haematological relapse was 8 – 79 days (median: 25 d). In the cases of subsequent development of haematological relapses, the levels of fusion transcript in CD34+ BM cells were one order of magnitude higher than in the BM or PB, even in the case of CD34- blasts. Nine patients were treated for 17 molecular relapses with following results: chemotherapy, CR=2, PR=3, NR=1; gemtuzumab ozogamicin, CR=3, PR=1, NR=3; IL-2±DLI, CR=3, NR=1 (PR was defined as a decrease in fusion transcript level at least 10-fold, CR as a decrease to 0). Patients with CD33- blasts at diagnosis did not respond to gentuzumab ozogamicin. Non-responsiveness to one treatment option did not mean non-responsiveness to another treatment. Conclusion: Frequent quantitative monitoring (especially in CD34+ BM cells) of fusion transcripts (in contrast to WT1) is useful for reliable prediction of haematological relapse in AML patients. PB seems to be sufficient for frequent outpatient MRD monitoring. Efficient targeting of LSCs will be essential for AML cure, however, the best method is currently not known. Some now available procedures are sometimes surprisingly successful.

Detection of Molecular Relapse of AML by Very Frequent Quantitative Monitoring of Different Molecular Markers (Fusion Transcripts and WT1) in Different Compartments (Peripheral Blood-PB, Bone Marrow-BM, and Selected CD34+ Bone Marrow Cells) and Its Treatment with Chemotherapy or Gemtuzumab Ozogamicin.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 4481-4481
Author(s):  
Jiri Mayer ◽  
Ivo Palasek ◽  
Zdenek Pospisil ◽  
Sona Struncova ◽  
Dana Dvorakova ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Bone Marrow Cells ◽  
Residual Disease ◽  
Subsequent Development ◽  
Fusion Transcript ◽  
Gemtuzumab Ozogamicin ◽  
Time Interval ◽  
Clinical Relapse ◽  
Fusion Transcripts ◽  
True Value

Abstract Patients and Methods. In order to find some markers, which reliably enable to predict clinical relapse in AML patients, we primarily focused on patients with the known fusion transcript (CBFB-MYH, AML1-ETO, or involving the MLL gene) and correlated this values with the WT1 for estimation of the true value of WT1 monitoring of disease behavior in a given patients. The value of different compartments for minimal residual disease (MDR) monitoring (PB, BM or CD34+ BM cells) was also analyzed. The study was prospective; in the case of MDR dynamics, the patients were actively called for earlier visit. This strategy could estimate the real time interval from MRD level increase to hematological relapse detection. In the interventional part of the study, the patients with already known MRD dynamics were treated at the time of molecular relapse. Results and Discussion. In 67 AML patients and 3 healthy volunteers, 2184 BM or PB samples were examined, including 240 samples from CD34+ BM cells. Follow-up was 31–252 weeks (median: 88 w). The correlation between the fusion transcripts levels in BM and PB was excellent (r=0.9676). The correlation between WT1 PB and BM levels was far less satisfactory. Since the WT1 values were frequently >0 even if the level of fusion transcript =0, we wanted to find some “normal” value for WT1. Using the ROC curves, however, we were not able to find any WT1 level being a confidential marker of molecular remission in either compartment (PB, BM or CD34+). Molecular relapse was defined as a reappearance of the fusion transcript detection or its 10-fold increase, repeatedly detected. The time from molecular to hematological relapse was 8–79 days (median: 25 d). In the cases of subsequent development of hematological relapses, the levels of fusion transcript in CD34+ BM cells were one order of magnitude higher than in the BM or PB, even in the case of CD34− blasts. Eight patients were treated for 13 molecular relapses with following results: chemotherapy, CR=2, PR=2; gemtuzumab ozogamicin, CR=3, PR=1, NR=3; IL-2±DLI, CR=2 (PR was defined as a decrease in fusion transcript level at least 10-fold). Patients with CD33− blast at diagnosis did not respond to gemtuzumab ozogamicin. Non-responsiveness to one treatment option did not mean non-responsiveness to another treatment. Conclusion: Fusion transcript monitoring enables reliable detection of molecular relapse in AML and high values in CD34+ BM cells signalize imminent hematological relapse (even in the case of CD34− blasts). PB is a suitable compartment for frequent monitoring. However, in some cases, relapse are fulminate, hardly allowing any intervention. WT1 does not seem to be a reliable marker for exact molecular relapse detection. AML at the stage of molecular relapse behaves similarly to AML at the frank hematological relapse: there are CRs, PRs, or NRs when using chemotherapy or gemtuzumab ozogamicin. AML with CD33− blasts at diagnosis does not seem to respond to gemtuzumab ozogamicin at the stage of molecular relapse. Success of AML therapy in the future seems to be dependant on efficient targeting the leukemia stem cell.

Significance of Minimal Residual Disease Monitored by Quantitative Assessment of WT1gene in Patients in First Remission of Acute Myeloid Leukemia Before Allogeneic Stem Cell Transplantation

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 4485-4485
Author(s):  
Veronika Válková ◽  
Jaroslav Polak ◽  
Marketa Markova ◽  
Hana Hájková ◽  
Antonin Vitek ◽  
...  
Keyword(s):  
Gene Expression ◽  
Myeloid Leukemia ◽  
Residual Disease ◽  
Conditioning Regimen ◽  
Wt1 Gene ◽  
Significant Difference ◽  
Induction Failure ◽  
Minimal Residual ◽  
Acute Myeloid

Abstract Abstract 4485 Purpose Thanks to the development of knowledge in the field of molecular biology, the great progress has been done in risk stratification of patients with acute myeloid leukemia (AML) at diagnosis, in recent years. Based on the recommendations of international expert groups there were identified the patients who may benefit from the allogeneic stem cell transplantation (allo-SCT) as a consolidation of first complete remission (CR). In the absence of an universal marker for minimal residual disease (MRD) measurements, there is still little information about the importance of MRD prior to allo-SCT. Our department has a very good experience with quantitative monitoring of WT1 gene expression as a marker of MRD during treatment of AML. The aim was to retrospectively evaluate the significance of MRD in patients indicated for allo-SCT in 1.CR. Patients and methods Overall 35 patients (pts) in the first morphological CR were transplanted from April 2005 - July 2011. Median age was 46 years (range; 20–63), mens 14, women 21, three good risk, intermediate risk 23, high risk 7 (NA 3). A total of 19 pts achieved CR after second induction (salvage), 11 pts were in 1st iCR. Induction 3+7 was given to 31 pts (4x other), as consolidation has been used HIDAC in 28 pts (7x other). As the graft, peripheral blood stem cells were used in 27 pts, bone marrow in 8 pts. The donor was identical sibling in 15 pts (1x mismatched sibling), matched unrelated donor (MUD) in 10 pts and mismatched UD in 9 pts. Conditioning regimen was myeloablative in 29 pts, reduced-intensity in 6 pts. Median follow-up was 18 months (range; 2–56). The expression of WT1 gene was measured by real-time polymerase chain reaction in peripheral blood according to the European Leukemia Net recommendations. The WT1 expression was related to the expression of a reference gene and the results were calculated with a number of WT1 copies related to 104 copies of ABL gene. The upper limit of normal WT1 expression was set as 50 copies of WT1 to 104 copies of ABL. Before allo-SCT, 25 pts were WT1-negative, ten pts were WT1-positive. Results When comparing the two groups according the MRD status, there was not significant difference in terms of age, risk groups, first induction failure, number of iCR, induction or consolidation type. Also, type of graft, conditioning regimen, or HSCT-CI was not significantly different. The group of WT1-positive pts had more unrelated donors, more aGVHD and shorter follow-up. In terms of cGVHD, the groups were comparable. When comparing the overall survival (OS) and cumulative relapse incidence (RI) of the entire group in terms of: risk group, first induction failure, iCR, consolidations number and incidence of aGVHD, we found no significant difference. Pts with cGVHD had a better OS, lower RI with comparable non-relapse mortality (NRM). In contrast, the MRD status measured by WT1 gene expression appears as clearly significant factor. The outcome of WT1-positive pts is significantly worse in terms of OS (55% vs 83% at 3 years, p = 0.03), RI (50% vs 11% at 3 years, p = 0.008), and there is a trend toward higher NRM (23% vs 5% in 3 years, p = 0.08). Conclusion Our results show that MRD status measured by WT1 gene expression in patients with AML in 1.CR significantly affects their future prognosis. Opportunities to influence the unfavorable prognosis of MRD-positive patients may be more intensive pre-transplantation therapy or earlier immunomodulatory intervention after allo-SCT (pre-emptive DLI). The larger prospective studies are necessary to confirm this hypothesis. The study was supported by scientific project MZ 00023736 granted by the Ministry of Health, Czech Republic. Disclosures: No relevant conflicts of interest to declare.

scholarly journals A clinically relevant population of leukemic CD34+CD38− cells in acute myeloid leukemia

Blood ◽  
2012 ◽  
Vol 119 (15) ◽  
pp. 3571-3577 ◽  
Author(s):  
Jonathan M. Gerber ◽  
B. Douglas Smith ◽  
Brownhilda Ngwang ◽  
Hao Zhang ◽  
Milada S. Vala ◽  
...  
Keyword(s):  
Stem Cells ◽  
Acute Myeloid Leukemia ◽  
Minimal Residual Disease ◽  
Myeloid Leukemia ◽  
Residual Disease ◽  
Clinical Relapse ◽  
Aldh Activity ◽  
Immunodeficient Mice ◽  
Minimal Residual ◽  
Acute Myeloid

Relapse of acute myeloid leukemia (AML) is thought to reflect the failure of current therapies to adequately target leukemia stem cells (LSCs), the rare, resistant cells presumed responsible for maintenance of the leukemia and typically enriched in the CD34+CD38− cell population. Despite the considerable research on LSCs over the past 2 decades, the clinical significance of these cells remains uncertain. However, if clinically relevant, it is expected that LSCs would be enriched in minimal residual disease and predictive of relapse. CD34+ subpopulations from AML patients were analyzed by flow cytometry throughout treatment. Sorted cell populations were analyzed by fluorescence in situ hybridization for leukemia-specific cytogenetic abnormalities (when present) and by transplantation into immunodeficient mice to determine self-renewal capacity. Intermediate (int) levels of aldehyde dehydrogenase (ALDH) activity reliably distinguished leukemic CD34+CD38− cells capable of engrafting immunodeficient mice from residual normal hematopoietic stem cells that exhibited relatively higher ALDH activity. Minimal residual disease detected during complete remission was enriched for the CD34+CD38−ALDHint leukemic cells, and the presence of these cells after therapy highly correlated with subsequent clinical relapse. ALDH activity appears to distinguish normal from leukemic CD34+CD38− cells and identifies those AML cells associated with relapse.

scholarly journals Molecular Minimal Residual Disease Detection in Acute Myeloid Leukemia

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. SCI-30-SCI-30
Author(s):  
Peter Valk
Keyword(s):  
Acute Myeloid Leukemia ◽  
Minimal Residual Disease ◽  
Myeloid Leukemia ◽  
Residual Disease ◽  
Fusion Transcript ◽  
Patient Specific ◽  
Molecular Abnormalities ◽  
Minimal Residual ◽  
Risk Of Relapse ◽  
Acute Myeloid

Abstract Minimal residual disease (MRD) detection based on the standardized molecular monitoring of the t(9;22)-related BCR-ABL1 fusion transcript is well established for patients with chronic myeloid leukemia (CML). The levels of BCR-ABL1 serve as a guide to tailor treatment of the CML patient. In acute myeloid leukemia (AML) MRD detection based on polymerase chain reaction (PCR) approaches targeted towards the acquired molecular abnormalities is less well established. MRD measurement of the CBFB-MYH11 and RUNX1-RUNX1T1 fusion transcripts after induction therapy has been shown to be of some clinical importance. However, these transcripts can persist during long term complete remission, without having an effect on treatment outcome. In contrast, sequential MRD monitoring of the PML-RARA fusion transcript in acute promyelocytic leukemia (APL) is a strong predictor of relapse. Initial molecular MRD studies were limited to these favorable AML subtypes. Due to the discovery of novel recurrent abnormalities in AML the potential of molecular MRD detection has increased substantially. Although, certain acquired mutations, such as those in NPM1, are known for a number of years, only recently the application of these molecular abnormalities for MRD detection has been investigated in larger clinical trials. By NPM1 mutant MRD detection we can now recognize patients with higher risk of relapse. Highly sensitive targeted detection of the hotspot mutations in AML subsets is feasible by means of real-time PCR, but detection of patient specific mutations with this technology is still challenging. Next generation sequencing (NGS) revealed that AML is an extremely heterogeneous disease, as illustrated by the multitude of acquired mutations, but this technology has also opened possibilities for detection of MRD in virtually every patient. With NGS there is no need for patient specific assays since practically all mutations are detected. These molecular abnormalities, as single marker or in combination, will most certainly improve MRD monitoring of AML. However, it remains yet to be determined how MRD levels are assessed and which combination of markers in a MRD detection result in clinically relevant information, requiring extensive validation in large clinical AML trials. Smaller studies already demonstrated the variable dynamics of MRD during treatment and associations between somatic mutations persistence and risk of relapse. However, clonal hematopoiesis of undetermined potential, i.e., preleukemic mutations that may persist after treatment, provides an extra layer of complexity to the applicability of MRD detection. For example, the clinical applicability of MRD detection in the setting of mutant DNMT3A and IDH mutations is likely less effective due to the persistent DNMT3A and IDH mutant preleukemic cells following treatment. However, should all mutations be cleared after treatment or can preleukemic mutations in otherwise normal hematopoiesis persist without resulting in relapse? Taken together, there is need for molecular approaches to understand the dynamics of residual disease in AML during treatment. Disclosures No relevant conflicts of interest to declare.

scholarly journals Novel and Rare Fusion Transcripts Involving Transcription Factors and Tumor Suppressor Genes in Acute Myeloid Leukemia

Cancers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1951 ◽  
Author(s):  
Antonella Padella ◽  
Giorgia Simonetti ◽  
Giulia Paciello ◽  
George Giotopoulos ◽  
Carmen Baldazzi ◽  
...  
Keyword(s):  
Acute Myeloid Leukemia ◽  
Transcription Factors ◽  
Myeloid Leukemia ◽  
Bone Marrow Cells ◽  
Chromosomal Translocation ◽  
Fusion Transcript ◽  
Sequencing Data ◽  
Fusion Transcripts ◽  
Acute Myeloid

Approximately 18% of acute myeloid leukemia (AML) cases express a fusion transcript. However, few fusions are recurrent across AML and the identification of these rare chimeras is of interest to characterize AML patients. Here, we studied the transcriptome of 8 adult AML patients with poorly described chromosomal translocation(s), with the aim of identifying novel and rare fusion transcripts. We integrated RNA-sequencing data with multiple approaches including computational analysis, Sanger sequencing, fluorescence in situ hybridization and in vitro studies to assess the oncogenic potential of the ZEB2-BCL11B chimera. We detected 7 different fusions with partner genes involving transcription factors (OAZ-MAFK, ZEB2-BCL11B), tumor suppressors (SAV1-GYPB, PUF60-TYW1, CNOT2-WT1) and rearrangements associated with the loss of NF1 (CPD-PXT1, UTP6-CRLF3). Notably, ZEB2-BCL11B rearrangements co-occurred with FLT3 mutations and were associated with a poorly differentiated or mixed phenotype leukemia. Although the fusion alone did not transform murine c-Kit+ bone marrow cells, 45.4% of 14q32 non-rearranged AML cases were also BCL11B-positive, suggesting a more general and complex mechanism of leukemogenesis associated with BCL11B expression. Overall, by combining different approaches, we described rare fusion events contributing to the complexity of AML and we linked the expression of some chimeras to genomic alterations hitting known genes in AML.

What Is New? An Update of the MLL Recombinome Including the Three Novel Partner Genes ABI2, PDS5A, and TOP3A

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1351-1351
Author(s):  
Claus Meyer ◽  
Mariana Emerenciano ◽  
Eva A Coenen ◽  
Eric Delabesse ◽  
Charles Herbaux ◽  
...  
Keyword(s):  
Acute Leukemia ◽  
Molecular Level ◽  
Conflicts Of Interest ◽  
Residual Disease ◽  
Patient Specific ◽  
Fusion Partner ◽  
Fusion Transcripts ◽  
Mll Gene ◽  
Diagnostic Center ◽  
Partner Gene

Abstract Abstract 1351 Chromosomal rearrangements of the MLL gene are associated with pediatric and adult de novo as well as therapy related acute myeloid leukemias, acute lymphoid leukemias, biphenotypic leukemias, and myelodysplastic syndromes. So far more than 70 MLL fusion partner genes have been characterized at the molecular level involving nearly all chromosomes. Though 11q23 rearrangements are associated with high-risk leukemias the clinical outcome of MLL rearrangements depends highly on the specific fusion partner involved. Nearly 40% of these partner genes have been identified at the Diagnostic Center of Acute Leukemia (DCAL) including the novel partner genes ABI2, PDS5A and TOP3A by analyzing more than 1400 MLL rearrangements. These rearrangements from 27 different countries include 52 different partner genes. This overview indicates all the specific introns of the translocation partner genes (TPGs) found to be involved in MLL translocations, their chromosomal locations and the type of genetic abnormality that is leading to the MLL fusion. More than 20% of all MLL rearrangements are complex ones. Within these complex rearrangements, the 5' part of the MLL gene is generally fused in frame to one of the most frequent partner genes. But the 3' part of the MLL gene is fused in many cases to a novel so-called “reciprocal MLL partner gene” like DENND4A or LRRTM4. To date more than 90 reciprocal MLL partner genes have been identified. In addition we present a recently analysed 4-way translocation where all four breakpoints could be identified by systematic breakpoint analysis using LDI-PCR. Also three novel “spliced MLL fusions”, a mechanism to generate functional chimeric fusion transcripts, involving MLLT4 (AF6), MYO1F, and CT45A2 have been identified at the DCAL. With these results, the number of genes involved in „spliced MLL fusions“ has increased from eight to eleven. Moreover we present the current breakpoint cluster region (bcr) for the 14 most frequent partner genes, namely AFF1 (AF4), MLLT3 (AF9), MLLT1 (ENL), MLLT10 (AF10), MLLT4 (AF6), ELL, EPS15, MLLT6 (AF17), SEPT6 (AF17), MLLT11 (AF1Q), SEPT9, AFF3 (LAF4), TET1, SEPT5 (PNUTL) and partial tandem duplications. For six patients, no partner gene could be identified at the molecular level and for 5 patients the identified fusion is out of frame. Unfortunetely all attemps to identify functional chimeric fusion transcripts by RACE and RT-PCR failed. These unusual MLL rearrangements probably represent a subclass of MLL abnormalities which have per se no or only a weak ability to transform hematopoeitic cells and are indentified only in the context of other hematopoeitic malignancies like the recently described MLL partner SACM1L. Finally, the determined patient-specific fusion sequences are succesfully used worldwide for minimal residual disease (MRD) monitoring to improve the treatment and outcome of acute leukemia patients. Disclosures: No relevant conflicts of interest to declare.

Sign in / Sign up

Export Citation Format

Share Document