GLORIA

GEOMAR Library Ocean Research Information Access

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • American Society of Hematology  (201)
Material
Publisher
  • American Society of Hematology  (201)
Language
Subjects(RVK)
  • 1
    In: Blood, American Society of Hematology, Vol. 131, No. 17 ( 2018-04-26), p. 1931-1941
    Abstract: EBV-induced DLBLs are characterized by genomic and transcriptomic alterations in the Rho pathway. Targeting the Rho pathway using a ROCK inhibitor, fasudil, inhibited tumor growth in EBV-positive DLBL patient-derived xenograft models.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2018
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Online Resource
    Online Resource
    American Society of Hematology ; 2010
    In:  Blood Vol. 116, No. 21 ( 2010-11-19), p. 1240-1240
    In: Blood, American Society of Hematology, Vol. 116, No. 21 ( 2010-11-19), p. 1240-1240
    Abstract: Abstract 1240 Use of reliable predictable factors in newly diagnosed chronic phase (CP) CML patients could ensure the most appropriate selection of therapy in individual patients, and the Sokal score which was developed in the pre-interferon era still retains prognostic values in patients treated with imatinib. In addition to the Sokal score, patients with a high BCR-ABL transcript level at diagnosis might respond differently to therapy. However, to our knowledge, there has been no distinct study to investigate the association between BCR-ABL transcript level at diagnosis and the response to therapy. It has been generally agreed that baseline BCR-ABL transcript levels are not relevant to predict the response to therapy, and the use of international scale (IS) is also based on the concept in which 100%IS is defined as the standardized baseline and 0.1%IS corresponds to major molecular response (MMR) in all CML patients. In this study, cytogenetic and molecular responses to the therapy was investigated in patients with high BCR-ABL transcript levels at diagnosis and patients with low BCR-ABL transcript levels at diagnosis to assess if baseline BCR-ABL transcript levels could be the reliable predictable factor in CP CML patients. Between May 2001 and Aug 2008, total 756 CML patients were treated with imatinib in St. Mary's Hospital of the Catholic University of Korea, and among them, 113 CP patients have been treated with imatinib at a dose of 400 mg/day for more than 6 months without interferon or stem cell transplantation prior to imatinib therapy. BM or PB samples were obtained at regular intervals from diagnosis for hematologic response (HR), cytogenetic response (CyR) and molecular response (MR) monitoring. For additional statistical analysis, 102 patients with Sokal scores available at the time of diagnosis were divided into 3 groups: low, intermediate and high Sokal groups. The median baseline BCR-ABL transcript level for 113 patients was 103.79%(IS), and the median BCR-ABL transcript levels were compared between 57 patients in a group of high baseline BCR-ABL levels and 56 patients in a group with low BCR-ABL levels by 3, 6, 12 and 18 months of imatinib therapy (Table 1). No difference was observed when the median values at month 3 and month 6 were considered, but from month 12 to month 18 after initiation of imatinib, the median BCR-ABL levels in patients with high baseline BCR-ABL levels was at least twice as high as median BCR-ABL levels in patients with low baseline BCR-ABL levels. However, differences cannot be considered to be significant due to the small number of patients under analysis. Regarding the CCyR rate by 3, 6, 12 and 18 months of imatinib therapy, no significant difference was observed between 2 groups of high and low baseline BCR-ABL levels, and there was also no statistically significant difference in CCyR and MMR rates depending on the baseline BCR-ABL levels even after grouping the patients according to Sokal scores.Table 1:Median BCR-ABL levels over time under imatinib treatment depending on the baseline BCR-ABL transcript levels.BaselineBCR-ABLtranscriptlevels (IS%)Month 3Month 6Month 12Month 18 〉 103.79n25534625median3.900.850.330.20range0.74 - 38.870 - 77.840 - 26.660 - 3.00 〈 103.79n36513122median4.110.950.150.07range0 - 183.300.001 - 41.980 - 8.040 - 2.51 In this study, no evidence of the correlation of the baseline BCR-ABL levels and the response to therapy was observed, and BCR-ABL level at diagnosis does not seem to give additional prognostic information to predict the response to therapy. Thus, the value of baseline BCR-ABL levels is still questionable to be used to identify patients who require higher dose of imatinib or more potent tyrosine kinase inhibitors, and further study with larger cohort and longer follow-up would be necessary to confirm whether baseline BCR-ABL levels are relevant to predict the response to therapy. Disclosures: No relevant conflicts of interest to declare.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2010
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    In: Blood, American Society of Hematology, Vol. 116, No. 21 ( 2010-11-19), p. 3443-3443
    Abstract: Abstract 3443 BCR-ABL kinase domain (KD) point mutation causes resistance to tyrosine kinase inhibitors (TKI) in CML patients through impaired binding of TKI to the target site. One of the characteristics of patients with BCR-ABL kinase domain point mutations is the fact that some patients have multiple mutations. However there have not been many studies showing that data about clinical relevance or dynamics of multiple mutation during CML treatment. From January 2002 to June 2010 at Seoul St Mary's Hospital, 277 CML patients were screened for mutation analysis due to sign of resistance to tyrosine kinase inhibitors including imatinib, nilotinib, dasatinib or bosutinib. We found that 95 patients have point mutation in BCR-ABL kinase domain through direct sequencing or ASO-PCR. Among them, 17 patients showed multiple mutation containing more than one type of point mutations in BCR-ABL KD. We investigated the patients with multiple mutations to characterize its clinical relevance and dynamics. Once mutation found, follow-up samples from the corresponding patients were collected and analyzed prospectively, or mutation status was analyzed retrospectively with cryopreserved samples if they were available. Status of the patients with multiple mutation is shown in Table 1. In order to investigate whether the multiple mutations are on same clone or on separated clone, we cloned serial samples from the 17 patients. Cloning of cDNA region corresponding to BCR-ABL KD into plasmid was performed and followed by transformation into competent cells, colony formation, plasmid preparation of 20 colonies from each sample, and then direct sequencing. Multiple mutations of 88% patients (15 out of 17) existed compound mutation which means the individual mutant types are located on the same BCR-ABL molecule. In addition of major mutation types which were detectable in direct sequencing analysis, all the patients showed to have minor types of mutations which were found only through BCR-ABL KD cloning and subsequent colony sequencing. To make sure that this minor mutation types were not caused by sequencing error, we also analyzed of 3 patients who showed TKI resistance, but had no BCR-ABL mutation. In addition, samples from 3 normal persons were analyzed with the same method. The frequency of appearance of the minor types of point mutation was reduced in the patient group who showed TKI resistance, but had no BCR-ABL mutation, and then dramatically decreased in the normal person group, indicating that BCR-ABL gene in patients with point mutation are relatively unstable. Analysis of serial samples from a same patient provided evidence of dynamic change of portion of compound mutation. In most case, portion of the clone containing compound mutation was increased as treatment went on, indicating the clone harboring compound mutation can take survival advantage over TKI treatment in comparison of the clone containing individual type of mutation. In addition, some patients showed change in individual mutation type comprising multiple mutation as treatment went on. Currently investigation of clinical relevance of compound mutation and other analyses are being carried on and more results will be provided in detail at the conference. Table 1. Patients Tx at mutation detection (mg) Compound type Compound % 1 Nilotinib400 G250E+T315I 6.7 G250E+D444G 33.3 T315I+D444G 6.7 2 Nilotinib400 M244V+T315I 95.0 3 Dasatinib100 Y253H+T315I 95.0 4 Dasatinib140 T315I+E459K 55.6 5 Dasatinib200 T315I+M351T 66.7 6 Dasatinib100 NCM Dasatinib80 NCM Dasatinib100 M244V+F359V 16.7 7 Bosutinib500 NCM 8 Dasatinib140 T315I+F359C 35.3 9 Imatinib400 E255K+T315I 5.6 10 Dasatinib80 E255V+T315I 90.0 11 Imatinib800 E255K+T315I 10.5 12 Nilotinib800 E255K+T315I 12.5 13 Dasatinib100 F311I+T315I 35.0 F311I+F317Lb 10.0 Imatinib400 F311I+T315I 10.0 F311I+F317La 15.0 F311I+F317Lb 55.0 14 Nilotinib800 Y253H+F359I 5.6 15 Bosutinib500 V299L+E459K 95.0 Nilotinib400 + Dasatinib100 V299L+F359I 5.0 V299L+E459K 55.0 V299L+F317La+E459K 15.0 V299L+F359I+E459K 15.0 V299L+F317La+F359I+E459K 5.0 16 Imatinib600 NCM 17 Imatinib400 NCM NCM: no compound mutation. Disclosures: No relevant conflicts of interest to declare.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2010
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    In: Blood, American Society of Hematology, Vol. 116, No. 21 ( 2010-11-19), p. 1726-1726
    Abstract: Abstract 1726 With prolonged imatinib therapy, BCR-ABL transcript levels measured by RQ-PCR assay show a progressive reduction, and some patients achieve complete molecular remission (CMR), which is defined as sustained undetectable BCR-ABL using RQ-PCR assay with a sensitivity of at least 4.5-log below the standardized baseline. However, due to the sensitivity limit of the current RQ-PCR technology, PCR negativity should not be considered as cure as more than 106 leukemic cells can still remain in the absence of detectable BCR-ABL transcripts by RQ-PCR. Although the numbers of patients with undetectable BCR-ABL are increasing with prolonged imatinib therapy and also with advent of more potent novel tyrosine kinase inhibitors (TKIs) such as dasatinib, nilotinib and bosutinib, currently there is no methodology to further classify the patients in CMR. In this study, digital PCR (dPCR) assay was applied for measurement of BCR-ABL transcript levels in patients with CMR to assess if more sensitive detection methodology can be implemented for molecular monitoring in CML. Between May 2001 and Aug 2008, total 757 CML patients were treated with imatinib in St. Mary's Hospital of the Catholic University of Korea, and 192 chronic phase (CP) CML patients have been under imatinib therapy for more than 2 years. Among them, 36 patients achieved PCR negativity at least once during imatinib treatment, and serial PB samples collected from the patients who have maintained CMR for at least 3 years in RQ-PCR were screened by dPCR. In dPCR assay, each sample was partitioned into hundreds to tens of thousands of reaction chambers, and this sample partitioning enables detecting extremely low copy numbers that would normally be undetectable by conventional RQ-PCR platforms. Using the BioMark Real-Time PCR System (Fluidigm) and 12.765 Digital Array (Fluidigm) in dPCR assay, only 1 liquid-transfer step is required to automatically partition each of 12 samples into 765 reaction chambers of approximately 4.6 ul (6 nl × 765), and pre-amplification step was performed prior to dPCR assay to improve the sensitivity. Regarding the detection limit, whereas down to 10-5 of cell line dilutions and down to 10-4 of patient sample dilutions were detectable using conventional RQ-PCR, dPCR showed 2–3 log improvement in the detection sensitivity limit by detecting down to 10-7 of cell line dilutions and patient sample dilutions. In all the patient samples collected at the first time point of PCR negativity, positive BCR-ABL signals were detected in dPCR assay, and gradual decrease in the number of positive signals were observed in the serial samples collected on yearly basis after achieving CMR. PB samples collected from 5 healthy individuals were also screened to confirm the significance of positive results in dPCR, and no amplification was detected in all of 5 samples. This study shows that the patients in CMR who is currently categorized based on the data derived from conventional RQ-PCR assay could be classified further using more sensitive methodology such as dPCR assay. In the previous studies on imatinib discontinuation, the selection criteria of candidates was solely based on the duration of PCR negativity prior to discontinuation, and conventional RQ-PCR was employed to measure PCR negativity. The fact that the absolute number of residual leukemia clones could not be measured under the detection limits of conventional RQ-PCR might have resulted in relapse in more than half of the patients, and it reflects that firm conclusions cannot be drawn about if a patient could safely discontinue the therapy solely based on conventional RQ-PCR. It might be necessary to have more sensitive assays which will allow further classification of patients who could be candidates for imatinib discontinuation without relapse. This study shows the potential of highly sensitive PCR approach for molecular monitoring, and dPCR examined here can be extended to expand our understanding of molecular profiles in CML patients and to correlate to clinical significance. Detection and quantitation of low copy numbers may help to more precisely follow-up the course of disease and thereby to more accurately tailor personalized therapeutic choices. Disclosures: No relevant conflicts of interest to declare.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2010
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Online Resource
    Online Resource
    American Society of Hematology ; 2006
    In:  Blood Vol. 108, No. 11 ( 2006-11-16), p. 5127-5127
    In: Blood, American Society of Hematology, Vol. 108, No. 11 ( 2006-11-16), p. 5127-5127
    Abstract: Systemic capillary leak syndrome (SCLS) is a rare condition characterized by episodic capillary hyperpermeability. The manifestations of this syndrome are generalized edema, hypotension, hypoalbuminemia, hemoconcentration, renal shut-down and monoclonal gammopathy. The pathogenesis of SCLS is still unclear. The treatment of SCLS is empirical, including theophylline, terbutaline, steroids, loop diuretics, plasmapheresis and BMT. Some patients were diagnosed multiple myeloma during follow-up. Death during the acute attack from cardiopulmonary collapse or diuresis phase from pulmonary edema occurs in approximately one third of the cases. Therefore initial fluid therapy is one of critical care point, but there is no information what is the adequate volume expander during acute attack. We experienced two cases of SCLS with severe acute attack and showed rapid improvement of hypotension by 10% pentastarch. Case 1: A 36-year-old woman visited our hospital with systolic blood pressure (SBP) 50 mmHg, resting dyspnea, oliguria and anasarca. The laboratory findings showed Hb 19.2 g/dL, hematocrit (Hct) 53%, total protein / albumin 3.7 / 1.7 g/dL, BUN / creatinine 32.6 / 1.9 mg/dL and monoclonal IgG-kappa. There was no evidence of multiple myeloma. We diagnosed the patient as having SCLS and started intravenous infusionof 9 L of normal saline (NS), dexamethasone, aminophylline and inotropics for 8 hours. Despite massive fluid therapy, SBP was not increased, and respiratory failure due to pulmonary edema was developed. After infusion of 10% pentastarch 0.5 L every 8 hours, SBP was gradually increased to normal within 12 hours without NS infusion. From the next day, diuresis phase started, other clinical and laboratory findings became normal range. There was no long-term sequale, and no more attack for 1 year follow-up. Case 2: A 36-year-old woman was referred to our hospital with severe hypovolemic shock and anasarca. The laboratory findings showed typical SCLS with the presence of monoclonal IgG-kappa. There was no evidence of multiple myeloma. She had histories of similar several episodes for 3 years, was managed with infusion of albumin, NS and suffered from pulmonary edema. At this time, clinical and laboratory findings were severe: confusion, anuria, SBP 40 mmHg, Hb 21.1 g/dL, Hct 63%, BUN / creatinine 22.6 / 2.8 mg/dL, total protein / albumin 4.4 / 2.5 g/dL. Two hours after using 0.5 L of 10% pentastarch and 2 L of NS, SBP and urine output increased to 127 mmHg and 50 ml/hour, respectively. Other clinical and laboratory findings restored and diuresis phase started within 1 day and there was no pulmonary edema. Acute management during hypotensive attack is very important to reduce mortality of SCLS. Because shift of fluid and protein by capillary hyperpermeability is the pathophysiology of this syndrome, total body fluid is not decreased. Thus massive crystalloid fluid, albumin infusion would not effective during hypotensive phase of SCLS and exacerbate edema. Hypoalbuminemia (molecular weight (MW) 69,000 dalton) is very common manifestation of SCLS, and Atkinson et al (Medicine1997; 56;225–39) reported that egress from vascular compartment was limited to proteins of MW up to 200,000 dalton. Under this knowledge, we used pentastarch (MW 240,000 dalton) during acute SCLS attacks and it showed dramatic responses. Pentastarch would be a very effective treatment for acute attack and might decrease acute mortality of SCLS.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2006
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    In: Blood, American Society of Hematology, Vol. 140, No. Supplement 1 ( 2022-11-15), p. 812-814
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2022
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    In: Blood, American Society of Hematology, Vol. 140, No. Supplement 1 ( 2022-11-15), p. 6774-6775
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2022
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    In: Blood, American Society of Hematology, Vol. 140, No. Supplement 1 ( 2022-11-15), p. 6782-6783
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2022
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    In: Blood, American Society of Hematology, Vol. 132, No. Supplement 1 ( 2018-11-29), p. 4493-4493
    Abstract: Introduction: We analyzed genomic profile in line with immune checkpoint molecule expression in multiple myeloma using whole genome sequencing (WGS) and whole transcriptome sequencing (WTS) data. Methods: We performed WGS of CD138+ selected tumor and the matched normal from saliva of multiple myeloma patients at 90-60x and 30x respectively from 37 patients. At the same time, we performed WTS using both tumor (CD138+) and immune milieu (CD138-) samples from these patients. Structural variations were called with Delly2 and Manta and the intersect of two call sets were used as the final SV calls. Copy number analysis was done with Sequenza and custom scripts. Somatic single nucleotide variants were identified with Mutect1 and Strelka and filtered against the panel of normal. RNA-seq was aligned using STAR algorithm and gene expression was quantified using RSEM algorithm. We extracted the expression of 21 immune checkpoint-related molecules (LAG3, PD-L1, IDO1, TIM3, CD27, CTLA-4, ICOS, TIGIT, PD-1, PD-L2, VISTA, and their ligands). To compare cell populations within a set of CD138-sorted MM samples, we used CIBERSORT algorithm to estimate predict fractions of leukocyte RNA. Results & Discussion: A total of 1,359 somatic structural variants were identified, with a median of 28 structural variant events per patient. The most common translocation event was t(4;14) (n=6, 16.2%). We identified novel recurrent deletions in CCSER1 (n=5, 13.5%) either deleting exon 10 (n=3) or exon 6 (n=2). CCSER1 has been proposed to a have a role in cell division with defects leading to cytokinetic defects. We observed an enrichment of whole-genome duplicated samples with CCSER1 deleted patients. We propose that CCSER1 deletion may have a role in whole-genome duplication events seen in multiple myeloma. Chromothripsis was also seen in 7 patients (18.9%). A total of 9 chromothripsis events were observed and chromosome 6 was most frequently involved (n=3). Recurrent mutation in IGKV4-1 chr2: 89185484 and 89185485 (p.Ala60) was observed suggesting dysfunctional antigen recognition in myeloma cells. From immune checkpoint perspective, expression of Galectin-9, a ligand of TIM3, was outstandingly high in immune milieu suggesting potential role of TIM3 inhibitor in myeloma. On the other hand, VISTA was highly expressed in tumors. When we matched the transcriptomic profiles with genomic variants, NRAS G61R mutant showed high expression of TIM3/Galectin-9 axis suggesting characteristics immune milieu of RAS mutant myeloma. Conclusions: We could identify novel CCSER1 recurrent deletion and IGKV4-1 mutation in multiple myeloma using WGS. WTS immune milieu analysis suggest potential role of TIM3 inhibitor in myeloma, especially in RAS mutated cases. Figure. Figure. Disclosures No relevant conflicts of interest to declare.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2018
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    In: Blood, American Society of Hematology, Vol. 138, No. Supplement 1 ( 2021-11-05), p. 3428-3428
    Abstract: Introduction FLT3-ITD is one of the most common and clinically relevant mutations in acute myeloid leukemia (AML). A high FLT3-ITD allelic ratio (AR) ( & gt;0.5) is strongly associated with poor prognosis. FLT3-ITDs are heterogeneous mutations, varying in sizes and locations with some patients having multiple FLT3-ITDs. Unfortunately, conventional clinical techniques are often not adequate in measuring these characteristics at sufficient resolution. The current study aimed to characterize an AML case with 2 FLT3-ITDs at diagnosis, map the multi-omic evolution of AML clones, and understand genetic patterns underlying AML relapse using single-cell proteogenomic sequencing (ScPGseq). Methods Leukemic samples from a 46-year old female patient diagnosed with de novo AML obtained at initial diagnosis and relapse were archived and used in this study. Based on the 2017 ELN risk stratification, the patient was classified into a low-risk group due to normal karyotype/low FLT3-ITD AR/NPM1+. The patient achieved complete remission (CR) after induction chemotherapy in combination with midostaurin. The patient relapsed 2 months after 4 cycles of consolidation, with a CR duration of 6 months. After relapse, the disease was refractory despite reinduction and salvage therapies, even with gilteritinib (Fig A). ScPGseq was performed using the Mission Bio's AML panel and antibody oligoconjugates for 16 cell surface proteins. Raw sequencing reads were processed using Mission Bio's Tapestri pipeline and results were exported from Tapestri Insights (v3.0.2). All downstream computational and statistical analyses were performed using R and Python. Results Consistent with clinical sequencing (R 2 = 0.997) and PCR, ScPGseq identified 5 mutations in FLT3 (21bp and 39bp ITDs and D835Y), NPM1, and WT1 at diagnosis (2367 cells). At relapse, 1 FLT3-ITD (21bp) and mutations in NPM1 and WT1 were detected while the other FLT3-ITD (39bp) and FLT3 D835Y were absent (2611 cells). Clonal analyses of mutation patterns identified 4 AML clones at diagnosis (C1-4) and 1 at relapse (C3R; Fig B). Two closely related clones, C3 and C3R (WT1+/NPM1+/21bp FLT3-ITD+) differed in zygosity of 21bp FLT3-ITD, where nearly all cells in C3R carries homozygous FLT3-ITD. SNP array confirmed the presence of copy neutral loss of heterozygosity (CN-LOH) in chr13q. Analysis of 16 cell surface proteins along with clonal information identified 3 clusters including one devoted to non-leukemic fractions (i.e., no mutations) (top) and another nearly exclusively consisting of mutant cells from diagnosis, which we termed "monocyte-like signature" (right bottom). The other cluster was composed of nearly all mutant cells from the relapse sample and about 1/3 of mutant cells from diagnosis, which we termed "immature myeloid cell signature" (left) (Fig C). When investigating further, C3 cells with immature myeloid cell signature (98/287 cells, 34.1%) exhibited much higher allelic burden of (mean 73% vs. 56%, adj. p & lt; 1.1e-6) and were significantly enriched with homozygous 21bp FLT3-ITDs compared to C3 cells with monocyte-like signature (189/287 cells, 65.9%) (41/98 cells, 42% vs. 11/189 cells, 5.8%, adj. p = 2.7e-13). No other mutations showed similar patterns. It indicates that C3R existed from the initial diagnosis at low frequency, instead of losing heterozygosity during relapse. Without the single cell proteogenomic analyses, C3R cells, present in & lt;5% cells at the initial diagnosis could have not been detected. The multi-omic information elucidates the complete clonal history of this AML (Fig D). Starting with WT1 and NPM1 mutations (C1), 3 FLT3 mutations (2 ITDs and D835Y) were subsequently acquired in 3 subclones (C2-4). A subset of C3 cells (WT1+/NPM1+/21bp FLT3-ITD+) further gained CN-LOH in chr13q (C3R at diagnosis). When treated, AML cells without homozygous 21bp FLT3-ITD were cleared. Cells with homozygous 21bp FLT3-ITD survived/escaped from the treatment and became the dominant clone at relapse (C3R at relapse). Conclusion The current study demonstrates that ScPGseq allows 1) simultaneous and comprehensive analyses of multiple FLT3-ITDs at the single-cell level 2) early detection of relapse clone with subclonal homozygous 21bp FLT3-ITD from the initial diagnosis, which explains one of the mechanisms of relapse in AML cases with low FLT3-ITD AR 3) multi-omic clonal analyses, which further refine clonal models relying only on mutation profiles. Figure 1 Figure 1. Disclosures Minden: Astellas: Consultancy. Kim: Pfizer: Honoraria, Research Funding; Bristol-Meier Squibb: Research Funding; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Paladin: Honoraria, Research Funding.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
    RVK:
    RVK:
    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2021
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...