pubmed > ABL1 > bone marrow

[Investigation of Laboratory and Clinical Feature in the Patients with Myeloproliferative Neoplasm Co-expression of BCR-ABL1 and JAK2 V617F].
To analyze the comprehensive laboratory test data of BCR-ABL1 fusion gene and JAK2 V617F mutation co-expressed in myeloproliferative neoplasm (MPN) patients, and investigate its relative clinical significance. Data of 1 332 MPN patients were comprehensively analyzed, BCR-ABL1 (P190/P210/P230) fusion gene and JAK2 V617F mutation were detected by real time-polymerase chain reaction (RT-PCR) technique, the CALR, MPL, JAK2 12 and 13 exon mutations were detected by the First Generation Sequencing, the bone marrow cell morphology and pathological characteristics were evaluated by bone marrow smear and biopsy technique, the immune phenotypes of bone marrow cells were evaluated by flow cytometry, the chromosome karyotypes of bone marrow cells were analyzed by chromosome G banding technique. Four of the 1 332 patients were found to have the co-existence of BCR-ABL1 fusion gene and the JAK2 V617F mutation, with a 0.3% incidence and a median age of 70 years old, including 2 cases of polycythemia vera, 1 case of primary myelofibrosis, and 1 case of chronic myeloid leukemia-accelerated phase. The clues of double positive genes of such patients at the time of initial diagnose could not be cued only by age, physical signs and cell morphology, they should be analyzed by comprehensive test data. The co-existence of BCR-ABL1 fusion gene and JAK2 V617F mutation in the same case is a kind of disease with special clinical significance. The application of multiple detection methods can improve the detection of this disease, which is conducive to early detection, reasonable diagnosis and treatment by clinicians. 共表达BCR-ABL1与JAK2 V617F的骨髓增殖性肿瘤患者实验室及临床特征分析. 分析BCR-ABL1融合基因和JAK2 V617F突变共表达的骨髓增殖性肿瘤(MPN)患者的实验室检测数据,探讨相关的临床意义. 综合分析1 332例初诊的MPN病例,应用RT-PCR方法检测BCR-ABL1(P190/P210/P230)融合基因及JAK2 V617F基因突变;一代测序方法检测CALR、MPL、JAK2 12和13号外显子突变;骨髓涂片及骨髓活检分析骨髓细胞形态及病理特征;流式细胞术分析骨髓血细胞免疫表型,G显带技术分析骨髓细胞染色体核型. 1 332例患者中4例同时存在BCR-ABL1融合基因和JAK2 V617F突变,发生率为0.3%,患者中位年龄70岁,2例为真性红细胞增多症,1例为原发性骨髓纤维化,1例为慢性髓细胞白血病-加速期。此类患者初诊时单从年龄、体征及细胞形态学上并未提示双阳性基因的线索,需通过综合的检测数据进行分析. BCR-ABL1融合基因和JAK2 V617F突变在同一个患者中共存是一类具有特殊临床意义的疾病,应用多种方法检测可提高此类疾病的检出,有利于临床医生早期发现、合理诊治.
Publication Date: 2021-08-08
Journal: Zhongguo shi yan xue ye xue za zhi

Comparison of Two Quantitative PCR-Based Assays for Detection of Minimal Residual Disease in B-Precursor Acute Lymphoblastic Leukemia Harboring Three Major Fusion Transcripts.
Two quantitative PCR (qPCR)-based methods, for clonal immunoglobulin or T-cell receptor gene (Ig/TCR) rearrangements and for fusion transcripts, are widely used for the measurement of minimal residual disease (MRD) in patients with B-precursor acute lymphoblastic leukemia (ALL). MRD of bone marrow samples from 165 patients carrying the three major fusion transcripts, including 74 BCR-ABL1, 54 ETV6-RUNX1, and 37 TCF3-PBX1, was analyzed by using the two qPCR-based methods. The correlation coefficient of both methods was good for TCF3-PBX1 (R
Publication Date: 2021-07-30
Journal: The Journal of molecular diagnostics : JMD

Unexpected pancytopenia: Dasatinib induced aplastic anemia in chronic myeloid leukemia.
The use of TKIs in CML has dramatically altered the natural course of the disease and improved outcomes for patients. TKIs overall have a very favorable safety profile. Dasatinib, a second generation TKI, is commonly used as a first-line treatment option in CML. We describe the first two reported cases of first-line dasatinib induced aplastic anemia in CML. In both patients, pancytopenia occurred within one year of diagnosis/starting dasatinib. Both bone marrow biopsies showed hypocellularity with mild fibrosis and persistent BCR-Abl1 positivity. Dose reduction was attempted without success in both patients. In one patient, multiple TKIs were trialed, while in the other, growth factor support was attempted; neither regimen was effective. Ultimately, the cytopenias associated with dasatinib were only resolved after immunosuppression in one patient and allogeneic stem cell transplant in the other patient. Prior reports have shown that aplasia/aplastic anemia can rarely be associated with imatinib and nilotinib. Here we show that dasatinib can lead to this phenomenon as well. This diagnosis should be considered in patients with CML who unexpectedly develop cytopenias.
Publication Date: 2021-06-22
Journal: Journal of oncology pharmacy practice : official publication of the International Society of Oncology Pharmacy Practitioners

BCR/ABL1-positive B-lymphoblastic Lymphoma Successfully Treated with Dasatinib-combined Chemotherapy.
We herein report a rare case of BCR-ABL1-positive B-lymphoblastic lymphoma (B-LBL). An 18-year-old woman had a history of persistent left-sided chest pain. Positron emission tomography showed increased metabolic activity in the fifth rib, duodenum, and pancreas. The pathological findings of the pancreas, duodenum, and bone marrow confirmed the diagnosis of B-LBL. Polymerase chain reaction of duodenum and bone marrow also revealed a minor BCR-ABL1 fusion gene. She was diagnosed with BCR-ABL1-positive B-LBL and administered dasatinib and prednisolone. She achieved complete remission two weeks after the initiation of the treatment. She received stem cell transplantation after consolidation chemotherapy and sustained complete remission.
Publication Date: 2021-04-06
Journal: Internal medicine (Tokyo, Japan)

Long-term safety and efficacy of givinostat in polycythemia vera: 4-year mean follow up of three phase 1/2 studies and a compassionate use program.
Polycythemia vera (PV) is a BCR-ABL1-negative myeloproliferative neoplasm (MPN) characterized by excessive proliferation of erythroid, myeloid, and megakaryocytic components in the bone marrow, mainly due to a Janus kinase 2 gene mutation (JAK2
Publication Date: 2021-03-08
Journal: Blood cancer journal

Extramedullary Blast Crisis of Chronic Myelogenous Leukemia With a Skin Lesion: A Case Report and Literature Review.
Extramedullary blast crisis of chronic myeloid leukemia (CML) is defined as extramedullary disease composed of blasts regardless of the proliferation of blasts in the bone marrow. The commonly affected sites are the lymph node, central nervous system, bone, skin, and soft tissue. However, skin infiltration of CML patients as the initial presentation while their bone marrow is still in the chronic phase is extremely rare. In this article, we present a case of a 51-year-old woman who was admitted to our hospital complaining about a skin nodule in her right calf and easy fatigability for 1 week. The peripheral blood and bone marrow analysis both supported the diagnosis of CML in the chronic phase, whereas the excisional biopsy specimen obtained from her right calf showed immature cells infiltration, and fluorescence in situ hybridization test was positive for p210 BCR/ABL1 gene rearrangement. Based on the presence of extramedullary myeloid sarcoma, the patient was diagnosed with extramedullary myeloid blast crisis of CML despite the chronic phase in the bone marrow.
Publication Date: 2021-01-23
Journal: The American Journal of dermatopathology

Contemporary treatment methods of adult patients with BCR/ABL1 positive chronic myeloid leukemia.
Chronic myeloid leukemia (CML) is a clonal myeloproliferative neoplasia that is characterised by Philadelphia chromosome (Ph1 chromosome) and/or fusion gene BCR-ABL1 in bone marrow. Interpheron α and bone marrow transplantation used to be the main treatment modalities for patients with CML 20 years ago. Due to the introduction of imatinib mesylate since the year 2000 the outcome of CML patients has dramatically improved. The survival of both younger and elderly patients in the case of an optimal response has been prolonged and currently is close to survival of healthy population. Although, one third of patients does not respond well to first line imatinib and needs to change the treatment to second line tyrosine kinase inhibitors (TKI: bosutinib, dasatinib and nilotinib). Younger patients without cardiologic and metabolic disorders and those with poor risk profile score may have benefit from TKI of 2nd generation as a 1st line treatment option with the aim of reaching deeper molecular response and the chance of treatment free remission (TFR) in future. By older patients with severe comorbidities and in patients with good risk profile score imatinib as a 1st line treatment option can be used. For patients who are resistant simultaneously to 2nd generation TKI and for patients with mutation T315I ponatinib - TKI of 3rd generation can be used effectively. Intolerance and toxicity of TKI´s are the main barriers of effective CML treatment. TKI selection for each patient should be individual. Patient´s cooperation with medical team is crucial and inevitable in long time treatment process. The chance for TFR has become feasible for approximately 40-60 % CML patients in deep and durable molecular remission and represents a further important milestone in the management of CML patients.
Publication Date: 2020-09-26
Journal: Vnitrni lekarstvi

Examination of clinically-derived p210 BCR/ABL1 RhoGEF mutations in a murine bone marrow transplantation model of CML.
Expression of the p210 BCR/ABL1 fusion protein has been described in virtually all patients with chronic myelogenous leukemia (CML). Previous studies have identified a guanine nucleotide exchange factor (RhoGEF) domain within BCR that is retained in p210 BCR/ABL1. Missense mutations at residues T654 (T654K) and F547 (F547L) within this domain have been reported in a CML patient in blast crisis (BC). In this study, we have evaluated p210 BCR/ABL1 constructs that contain these substitutions in a murine bone marrow transplantation (BMT) model of CML. The mutants exhibit normal expression and tyrosine kinase activity but altered signaling. When examined in the BMT assay, mice that express the mutants exhibit earlier onset of disease but have significantly extended lifespans relative to mice that express unmodified p210 BCR/ABL1. While mice that express p210 BCR/ABL1 exhibit neutrophilia that progresses to a less differentiated phenotype at death, disease in the mutant mice is characterized by eosinophilia with no maturation arrest. This observation was confirmed in vitro using myeloid cells and was associated with enhanced p53 phosphorylation and G1/S arrest. These results suggest that residues within the RhoGEF domain of p210 BCR/ABL1 can influence disease progression.
Publication Date: 2020-09-07
Journal: Leukemia research

Allogeneic haematopoietic stem cell transplantation improves outcome of adults with relapsed/refractory Philadelphia chromosome-positive acute lymphoblastic leukemia entering remission following CD19 chimeric antigen receptor T cells.
Relapsed/refractory Philadelphia chromosome-positive acute lymphoblastic leukemia (r/r Ph+ ALL) has an extremely poor prognosis. Chimeric antigen receptor T-cell (CART) therapy has acquired unprecedented efficacy in B-cell malignancies, but its role in the long-term survival of r/r Ph+ ALL patients is unclear. We analyzed the effect of CART on 56 adults with r/r Ph+ ALL who accepted split doses of humanized CD19-targeted CART after lymphodepleting chemotherapy. 51/56 (91.1%) achieved complete remission (CR) or CR with inadequate count recovery (CRi), including 38 patients with negative minimal residual disease (MRD) tested by bone marrow BCR-ABL1 copies. Subsequently, 30/51 CR/CRi patients accepted consolidative allogeneic haematopoietic stem cell transplantation (alloHSCT). Their outcomes were compared with those of 21/51 contemporaneous patients without alloHSCT. The 2-year overall survival (OS) and leukemia-free survival (LFS) of CR/CRi patients with alloHSCT were significantly superior to those without alloHSCT (58.9%, CI 49.8-68.0% vs. 22.7%, CI 12.7-32.7%, p = 0.005; 53.2%, CI 43.6-62.8% vs. 18.8%, CI 9.2-28.4%, p = 0.000, respectively). Multivariate analysis revealed that alloHSCT and MRD-negative post-CART were the independent prognostic factors for OS and LFS. CART therapy is highly effective for r/r Ph+ ALL patients, and consolidative alloHSCT could prolong their OS and LFS.
Publication Date: 2020-06-26
Journal: Bone marrow transplantation

Chronic Myeloid Leukemia: Atypical Presentation and Diagnostic Pitfall in the Workup of Isolated Thrombocytosis.
Chronic myeloid leukemia (CML) is one of the classic types of myeloproliferative neoplasms. It typically manifests with leukocytosis, but rarely with isolated thrombocytosis. Here we describe a unique case of isolated thrombocytosis as an initial presentation of CML in a 21-year-old woman, where the BCR-ABL1 fusion gene was detected in bone marrow (BM) aspiration and biopsy specimen after a negative peripheral blood (PB) fluorescence in situ hybridization testing. It is crucial to pursue workup for patients with isolated thrombocytosis through testing for the presence of the BCR-ABL fusion gene or the Philadephia chromosome in both PB and the BM in order to distinguish CML from essential thrombocythemia.
Publication Date: 2020-06-13
Journal: Cureus

Ultra-accurate Duplex Sequencing for the assessment of pretreatment ABL1 kinase domain mutations in Ph+ ALL.
Mutations of ABL1 are the dominant mechanism of relapse in Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL). We performed highly accurate Duplex Sequencing of exons 4-10 of ABL1 on bone marrow or peripheral blood samples from 63 adult patients with previously untreated Ph + ALL who received induction with intensive chemotherapy plus a BCR-ABL1 TKI. We identified ABL1 mutations prior to BCR-ABL1 TKI exposure in 78% of patients. However, these mutations were generally present at extremely low levels (median variant allelic frequency 0.008% [range, 0.004%-3.71%] and did not clonally expand and lead to relapse in any patient, even when the pretreatment mutation was known to confer resistance to the TKI received. In relapse samples harboring a TKI-resistant ABL1 mutation, the corresponding mutation could not be detected pretreatment, despite validated sequencing sensitivity of Duplex Sequencing down to 0.005%. In samples under the selective pressure of ongoing TKI therapy, we detected low-level, emerging resistance mutations up to 5 months prior to relapse. These findings suggest that pretreatment ABL1 mutation assessment should not guide upfront TKI selection in Ph + ALL, although serial testing while on TKI therapy may allow for early detection of clinically actionable resistant clones.
Publication Date: 2020-05-28
Journal: Blood cancer journal

[18F-fluorodeoxyglucose-positron emission tomography imaging before and after treatment of chronic-phase chronic myeloid leukemia with tyrosine kinase inhibitors].
A 64-year-old man presented with abnormal imaging results on 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET), showing moderately increased FDG-uptake in the entire bone marrow. Blood tests revealed leukocytosis, thrombocytosis, and increased lactate dehydrogenase levels. Furthermore, the neutrophil alkaline phosphatase score decreased. Bone marrow examination revealed marked hypercellularity of myeloid and megakaryocytic lineages without an excess of blasts. Cytogenetic analysis of the bone marrow demonstrated Philadelphia chromosome, and fluorescence in situ hybridization analysis was positive for BCR-ABL1 fusion genes. Thus, the patient was diagnosed with chronic myeloid leukemia (CML) in the chronic phase and tyrosine kinase inhibitor therapy with 100 mg of dasatinib daily was initiated. Complete cytogenetic response and a major molecular response were achieved at 3 and 12 months post-treatment, respectively. FDG-uptake values of the bone marrow remarkably decreased along with the remission status of the disease. FDG-PET images at pre- and post-treatment of CML are rarely compared, so we report this case as an important reference.
Publication Date: 2020-05-08
Journal: [Rinsho ketsueki] The Japanese journal of clinical hematology

Management of myelofibrosis after ruxolitinib failure.
Myelofibrosis is a BCR-ABL1-negative myeloproliferative neoplasm characterized by anemia, progressive splenomegaly, extramedullary hematopoiesis, bone marrow fibrosis, constitutional symptoms, leukemic progression, and shortened survival. Constitutive activation of the Janus kinase/signal transducers and activators of transcription (JAK-STAT) pathway, and other cellular pathways downstream, leads to myeloproliferation, proinflammatory cytokine expression, and bone marrow remodeling. Transplant is the only curative option for myelofibrosis, but high rates of morbidity and mortality limit eligibility. Several prognostic models have been developed to facilitate treatment decisions. Until the recent approval of fedratinib, a JAK2 inhibitor, ruxolitinib was the only available JAK inhibitor for treatment of intermediate- or high-risk myelofibrosis. Ruxolitinib reduces splenomegaly to some degree in almost all treated patients; however, many patients cannot tolerate ruxolitinib due to dose-dependent drug-related cytopenias, and even patients with a good initial response often develop resistance to ruxolitinib after 2-3 years of therapy. Currently, there is no consensus definition of ruxolitinib failure. Until fedratinib approval, strategies to overcome ruxolitinib resistance or intolerance were mainly different approaches to continued ruxolitinib therapy, including dosing modifications and ruxolitinib rechallenge. Fedratinib and two other JAK2 inhibitors in later stages of clinical development, pacritinib and momelotinib, have been shown to induce clinical responses and improve symptoms in patients previously treated with ruxolitinib. Fedratinib induces robust spleen responses, and pacritinib and momelotinib may have preferential activity in patients with severe cytopenias. Reviewed here are strategies to ameliorate ruxolitinib resistance or intolerance, and outcomes of clinical trials in patients with myelofibrosis receiving second-line JAK inhibitors after ruxolitinib treatment.
Publication Date: 2020-03-22
Journal: Annals of hematology

Dual oligopeptides modification mediates arsenic trioxide containing nanoparticles to eliminate primitive chronic myeloid leukemia cells inside bone marrow niches.
Chronic myeloid leukemia (CML) is one type of hematopoietic stem cell diseases. Although BCR-ABL1 tyrosine kinase inhibitors are remarkably effective in inducing remission in chronic phase patients, they are not curative in a majority of patients due to their failure to eradicate residual CML stem/progenitor cells, which reside in bone marrow niches. Here, we presented novel dual oligopeptides-conjugated nanoparticles and demonstrated their effective delivery of arsenic trioxide in bone marrow niches for the elimination of primitive CML cells. We encapsulated As-Ni transitional metal compounds into polymeric nanoparticles based on the reverse micelle rationale. The loading density and stability of arsenic trioxide in nanoparticles were improved. In vitro experiments demonstrated that dual oligopeptides conjugated nanoparticles could deliver arsenic trioxide into bone marrow niches including endosteal niches and vascular niches. The colony-forming activity of CML cells was remarkably restrained in the presence of metaphyseal bone fragments pre-incubated with bone marrow niche targeted arsenic nanoparticles. The in vitro vascular niche model suggested that CML cell proliferation was also successfully inhibited through a tight contact with HUVECs, which were pre-treated using niche-targeted arsenic nanoparticles. This bone marrow niche targeted delivery strategy has a potential usage for the treatment of CML and other malignant hematologic disorders originated from the bone marrow.
Publication Date: 2020-03-01
Journal: International journal of pharmaceutics

Comparison of BCR-ABL1 quantification in peripheral blood and bone marrow using an International Scale-standardized assay for assessment of deep molecular response in chronic myeloid leukemia.
Background Monitoring of molecular response (MR) using quantitative polymerase chain reaction (PCR) for BCR-ABL1 is a pivotal tool for guiding tyrosine kinase inhibitor therapy and the long-term follow-up of patients with chronic myeloid leukemia (CML). Results of MR monitoring are standardized according to the International Scale (IS), and specific time-dependent molecular milestones for definition of optimal response and treatment failure have been included in treatment recommendations. The common practice to use peripheral blood (PB) instead of bone marrow (BM) aspirate to monitor the MR monitoring in CML has been questioned. Some studies described differences between BCR-ABL1 levels in paired PB and BM specimens. Methods We examined 631 paired PB and BM samples from 283 CML patients in a retrospective single-center study using an IS normalized quantitative reverse transcription (qRT)-PCR assay for quantification of BCR-ABL1IS. Results A good overall concordance of BCR-ABL1IS results was found, a systematic tendency towards higher BCR-ABL1IS levels in PB was observed in samples of CML patients in a major MR. This difference was most pronounced in patients treated with imatinib for at least 1 year. Importantly, the difference resulted in a significantly lower rate of deep MR when BCR-ABL1IS was assessed in the PB compared to BM aspirates. Conclusions In summary, our data suggest that the classification of deep MR in patients with CML is more stringent in PB than in BM. Our study supports the current practice to primarily use PB for long-term molecular follow-up monitoring in CML.
Publication Date: 2020-02-23
Journal: Clinical chemistry and laboratory medicine

[MYC gene amplification attributed to double minutes in a patient with atypical chronic myeloid leukemia].
A 61-year-old man was admitted to our hospital with fever and massive leukocytosis. A bone marrow smear revealed an increased density of myeloid cells in various stages of maturation as well as dysplasia in the neutrophils. There was no proliferation of blasts, eosinophils, or basophils. Genomic analysis of the bone marrow cells revealed no detectable abnormalities associated with myeloproliferative neoplasms, including BCR-ABL1. Therefore, the patient was diagnosed with atypical chronic myeloid leukemia (aCML). Chromosomal analysis revealed the presence of 1-17 double minute chromosomes (dmin) in 20 of 20 tumor cells examined. Multiple MYC signals were detected via interphase fluorescence in situ hybridization, indicating MYC gene amplification in the dmins. Three months after the oral administration of hydroxyurea, leukocytosis reoccurred. Therefore, induction therapy followed with umbilical cord blood transplantation was performed. However, MYC signals remained detectable in the bone marrow sample obtained immediately after neutrophil engraftment, indicating the presence of residual tumor cells. To the best of our knowledge, this is the first case report of aCML with dmin gene amplification, suggesting that the dmin MYC amplification exacerbated the patient's disease.
Publication Date: 2019-12-17
Journal: [Rinsho ketsueki] The Japanese journal of clinical hematology

Hyper-activation of Aurora kinase a-polo-like kinase 1-FOXM1 axis promotes chronic myeloid leukemia resistance to tyrosine kinase inhibitors.
Chronic myeloid leukemia (CML) is a myeloproliferative disease caused by the constitutive tyrosine kinase (TK) activity of the BCR-ABL1 fusion protein. Accordingly, TK inhibitors have drastically changed the disease prognosis. However, persistence of the transformed hematopoiesis even in patients who achieved a complete response to TK inhibitors and the disease relapse upon therapy discontinuation represent a major obstacle to CML cure. Thiostrepton, Danusertib and Volasertib were used to investigate the effects of FOXM1, AKA and Plk1 inhibition in K562-S and K562-R cells. Apoptotic cell death was quantified by annexin V/propidium iodide staining and flow cytometry. Quantitative reverse transcription (RT)-PCR was used to assess BCR-ABL1, FOXM1, PLK1 and AURKA expression. Protein expression and activation was assessed by Western Blotting (WB). Clonogenic assay were performed to confirm K562-R resistance to Imatinib and to evaluate cells sensitivity to the different drugs. Here we proved that BCR-ABL1 TK-dependent hyper-activation of Aurora kinase A (AURKA)-Polo-like kinase 1 (PLK1)-FOXM1 axis is associated with the outcome of Imatinib (IM) resistance in an experimental model (K562 cell line) and bone marrow hematopoietic cells. Notably, such a biomolecular trait was detected in the putative leukemic stem cell (LSC) compartment characterized by a CD34+ phenotype. Constitutive phosphorylation of FOXM1 associated with BCR-ABL1 TK lets FOXM1 binding with β-catenin enables β-catenin nuclear import and recruitment to T cell factor/lymphoid enhancer-binding factor (TCF/LEF) transcription complex, hence supporting leukemic cell proliferation and survival. Lastly, the inhibition of single components of AURKA-PLK1-FOXM1 axis in response to specific drugs raises the expression of growth factor/DNA damage-inducible gene a (GADD45a), a strong inhibitor of AURKA and, as so, a critical component whose induction may mediate the eradication of leukemic clone. Our conclusion is that AURKA, PLK1 and FOXM1 inhibition may be considered as a promising therapeutic approach to cure CML.
Publication Date: 2019-05-28
Journal: Journal of experimental & clinical cancer research : CR

Potential Leukemic Cells Engraftment After Hematopoietic Stem Cell Transplantation From Unrelated Donors With Undiagnosed Chronic Leukemia.
Donor-related neoplasms are a potential complication of treatment strategies involving stem cell transplantation. Although mechanisms for detection of short-term complications after these procedures are well developed, complications with delayed onset, notably transmission of chronic diseases such as chronic myeloid leukemia (CML), have been difficult to assess. Consequently, we studied the potential of human CML cells to engraft hematopoietic tissues after intravenous implantation in mice. Human peripheral blood cells, collected from CML patients presenting with moderately increased white blood cells count before treatment, were transplanted into sub-lethally irradiated, immunodeficient mice. Five weeks after transplantation the nuclear cells were isolated from the murine bone marrow, spleen, and peripheral blood and were used to quantitatively detect human CD45 antigen by flow cytometry; qRT-PCR was used to detect the BCR-ABL1 fusion gene, and the human or murine beta-glucuronidase housekeeping gene was used to examine human-murine chimerism. We found that all evaluated animals had donor chimerism at the selected interval after transplant and the presence of a specific BCR-ABL1 fusion gene transcript was also detected. Our results suggest that the risk of neoplasm transmission cannot be eliminated during hematopoietic stem cell transplantation from undiagnosed CML donors with borderline leukocytosis. The obtained data confirms the potential of leukemic cells to viably engraft the hematopoietic organs post-transplantation in an immunosuppressed recipient.
Publication Date: 2018-12-05
Journal: Transplantation proceedings

Finding the right BCR-ABL1 tyrosine kinase inhibitor: a case report of successful treatment of a patient with chronic myeloid leukemia and a V299L mutation using nilotinib.
Chronic myeloid leukemia can be effectively treated with BCR-ABL1 tyrosine kinase inhibitors. However, BCR-ABL1 mutations can develop and cause secondary resistance to these inhibitors. For each of the available BCR-ABL1 inhibitors, certain mutations are known to be associated with resistance, although most mutations that confer resistance to one tyrosine kinase inhibitor remain sensitive to one or more of the other available inhibitors. For patients displaying poor response or loss of response to frontline treatment, the possibility that they have developed a new BCR-ABL1 mutation must be considered, and selection of a second-line treatment must consider the patient's mutational profile. Here we describe a case in which a patient developed a V299L mutation; although this mutation is known to be associated with resistance to dasatinib while remaining sensitive to nilotinib, limited information is currently available regarding the use of second-line nilotinib following development of a V299L mutation while receiving dasatinib. A 73-year-old man presenting with fatigue and drenching night sweats lasting for 2 weeks was diagnosed with chronic myeloid leukemia based on an analysis of a bone marrow biopsy and detection of the BCR-ABL1 fusion gene in peripheral blood. The patient initiated frontline treatment with dasatinib. A good treatment response was seen initially, with a complete hematologic response by month 2 of treatment. By month 20 however, BCR-ABL1 transcript levels rose markedly, and a mutational analysis revealed a BCR-ABL1 V299L mutation. Based on the identification of this specific mutation, the patient switched treatment to nilotinib; by month 18 of nilotinib treatment, the patient achieved a deeper reduction in BCR-ABL1 transcript levels than was seen with dasatinib. To date, in month 34 of treatment with nilotinib, the patient has shown good tolerance of the drug and has no clinical evidence of disease progression. Our case report illustrates the benefit of having multiple drugs available to treat chronic myeloid leukemia, each with the ability to inhibit a distinct set of BCR-ABL1 mutations. This patient's case suggests that switching to nilotinib can be an effective treatment option for patients who develop a BCR-ABL1 V299L mutation while receiving dasatinib.
Publication Date: 2018-11-14
Journal: BMC cancer

Bone marrow core biopsy in 508 consecutive patients with chronic myeloid leukemia: Assessment of potential value.
The diagnosis of chronic myeloid leukemia (CML) is based on characteristic clinical and laboratory findings and the presence of BCR/ABL1 in the blood and/or bone marrow (BM). The utility of BM core biopsy in the workup of patients with CML has been questioned. The potential added value of BM biopsy versus aspiration in the workup of a single-institution series of 508 patients with CML at their initial presentation was systematically assessed. BM biopsy was considered essential when it was needed to establish the disease phase, often because blast counts derived from aspirate smears were misleading because the biopsy specimen was more representative of the disease. BM biopsy was considered helpful if it was needed for other nonessential reasons. In 127 patients (25%), BM biopsy was either essential (109 patients) or helpful (18 patients). Patients with accelerated-phase (AP) or blast-phase (BP) disease often required a biopsy related to essential reasons. High-grade myelofibrosis (MF) was more frequent in patients with AP/BP disease than patients with chronic-phase disease (P = .0005), and the identification of BP disease required a BM biopsy assessment in 75% of the patients (P = .001). A follow-up BM evaluation more often yielded inadequate aspirates in patients with inadequate BM aspirates at the time of their initial diagnosis. BM core biopsy remains valuable in the workup of 25% of patients with CML because it facilitates identification of the disease phase or MF. The initial grade of MF is associated with the disease stage and outcome after therapy. BM biopsy is, therefore, indicated for patients with CML who have AP/BP disease or other findings suggestive of progressive disease.
Publication Date: 2018-10-16
Journal: Cancer

bcr-abl1 kinase domain(6)

jak2 v617f mutation(4)

bcr-abl1 gene rearrangement(4)

vera pv(9)

q34 q11(7)

thrombocythemia et(7)

neoplasms mpns(7)

chronic phase(7)

philadelphia ph(6)

pdgfra pdgfrb(6)

myelofibrosis pmf(6)

leukaemia cml(4)

blood pb(4)

leukemia b-all(4)

reaction rt-pcr(4)

inhibitors tkis(4)

imatinib im(3)