pubmed > ABL1 > fusion gene

ABL1 and Cofilin1 promote T-cell acute lymphoblastic leukemia cell migration.
The fusion gene of ABL1 is closely related to tumor proliferation, invasion, and migration. It has been reported recently that ABL1 itself is required for T-cell acute lymphoblastic leukemia (T-ALL) cell migration induced by CXCL12. Further experiments revealed that ABL1 inhibitor Nilotinib inhibited leukemia cell migration induced by CXCL12, indicating the possible application of Nilotinib in T-ALL leukemia treatment. However, the interacting proteins of ABL1 and the specific mechanisms of their involvement in this process need further investigation. In the present study, ABL1 interacting proteins were characterized and their roles in the process of leukemia cell migration induced by CXCL12 were investigated. Co-immunoprecipitation in combination with mass spectrometry analysis identified 333 proteins that interact with ABL1, including Cofilin1. Gene ontology analysis revealed that many of them were enriched in the intracellular organelle or cytoplasm, including nucleic acid binding components, transfectors, or co-transfectors. Kyoto Encyclopedia of Genes and Genomes analysis showed that the top three enriched pathways were translation, glycan biosynthesis, and metabolism, together with human diseases. ABL1 and Cofilin1 were in the same complex. Cofilin1 binds the SH3 domain of ABL1 directly; however, ABL1 is not required for the phosphorylation of Cofilin1. Molecular docking analysis shows that ABL1 interacts with Cofilin1 mainly through hydrogen bonds and ionic interaction between amino acid residues. The mobility of leukemic cells was significantly decreased by Cofilin1 siRNA. These results demonstrate that Cofilin1 is a novel ABL1 binding partner. Furthermore, Cofilin1 participates in the migration of leukemia cells induced by CXCL12. These data indicate that ABL1 and Cofilin1 are possible targets for T-ALL treatment.
Publication Date: 2021-09-12
Journal: Acta biochimica et biophysica Sinica

Genomic Copy Number Variants in CML Patients With the Philadelphia Chromosome (Ph+): An Update.
Submicroscopic segmental imbalances detected by array-comparative genomic hybridization (array-CGH) were discovered to be common in chronic myeloid leukemia (CML) patients with Karyotyping tests were performed on 106 CML patients during January 2010-September 2019 in our Genetics Laboratory. Eighty-four (79.2%) patients had the Philadelphia (Ph) chromosome as the sole chromosomal anomaly. Only 49(58.3%) of these 84 patients had sufficient marrow or leukemia blood materials to additionally be included in the array-CGH analysis. Fluorescence 11(22.4%) out of the 49 patients were found to have one to three somatic segmental somatic segmental (CNVs), including fourteen deletions and three duplications. The common region associated with deletions was on 9q33.3-34.12. Identified in five (45.5%) of the 11 positive patients with segmental CNVs, the deletions ranged from 106 kb to 4.1 Mb in size. Two (18.2%) cases had a deletion in the ABL1-BCR fusion gene on der (9), while three (27.3%) cases had a deletion in the ASS1 gene. The remaining CNVs were randomly distributed on different autosomes. Subtle genomic CNVs are relatively common in CML patients without cytogenetically visible additional chromosomal aberrations (ACAs). Long-term studies investigating the potential impact on patient prognosis and treatment outcome is underway.
Publication Date: 2021-08-28
Journal: Frontiers in genetics

[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

Practical management of side effects of tyrosine kinase inhibitor therapy in chronic myeloid leukemia
Összefoglaló. A krónikus myeloid leukaemia ritka, klonális őssejt eredetű betegség. A myeloid sejtsor kóros működését a 9-es és 22-es kromoszómák reciprok transzlokációja következtében kialakuló fúziós gén (BCR/ABL1) által kódolt patológiás (fokozott) aktivitású tirozin-kináz jelátviteli fehérje okozza. A tartós, gyakran élethosszig tartó BCR/ABL1 specifikus tirozin-kináz-gátló (TKI-) kezelés a betegek jelentős hányadában az egészséges populáció túlélését elérő teljes gyógyulást biztosít, melyhez folyamatos, a mindenkori szakmai ajánlásoknak megfelelő onkohematológiai ellenőrzés szükséges. Az igen hatékony TKI-kezelés mellett azonban nemkívánatos mellékhatások jelentkezhetnek, melyek - számos szervrendszert érintve - a krónikus myeloid leukaemiás beteg kezelését multidiszciplináris együttműködéssé szélesítik ki. Jelenleg Magyarországon ötféle TKI érhető el, melyek mellékhatásprofilja igen eltérő. A kezelés elindításakor, illetve terápiamódosítás esetén beteg- és kórképspecifikus szempontokat mérlegelve kell kiválasztani az adott TKI-kezelést. Tekintettel a tartós kezelés mellett elérhető kiváló túlélési eredményekre, egyre gyakoribb azoknak a krónikus myeloid leukaemiás betegeknek a száma, akiknél változó súlyosságú nemkívánatos mellékhatások jelentkeznek, melyek miatt a betegek sokszor nem a hematológus szakorvosnál jelentkeznek. A leggyakrabban észlelt szövődmények ismertetését saját beteganyagunk részletes elemzése kapcsán a mindennapi klinikai gyakorlatban is bemutatjuk. Igen fontos, hogy a társszakmák (háziorvos, belgyógyász, kardiológus, angiológus, diabetológus, tüdőgyógyász, gasztroenterológus stb.) gyakorlói is tisztában legyenek az adott TKI-kezelés lehetséges mellékhatásaival, azok megelőzésével, időben történő felismerésével és hatékony kezelésével. Szakmai közreműködésük révén így segíthetik a klinikai hematológust a megfelelő terápia megtervezésében, valamint a betegek folyamatos kezelése kapcsán gyakran szükségessé váló szakmaspecifikus gondozásában is. Orv Hetil. 2021; 162(30): 1198-1207. Summary. Chronic myeloid leukemia is a rare clonal stem cell disorder. The pathological overproduction of the myeloid cell line is caused by abnormal function of a tyrosine kinase encoded by a fusion gene (BCR/ABL1) which is formed upon a reciprocal translocation of chromosomes 9 and 22. Long-term, often lifelong treatment with BCR/ABL1-specific tyrosine kinase inhibitors provides excellent disease control and overall survival rates close to the general survival of a healthy population in a significant proportion of patients. These patients require continuous oncohematological monitoring in accordance with the current diagnostic and treatment guidelines. However, undesirable side effects may occur that extend the treatment of the patients to a multidisciplinary approach involving a number of nonhematological specialities. Currently, five types of tyrosine kinase inhibitors are available in Hungary, with very different side effect profiles. At the start of treatment or in the event of a change in therapy, patient- and leukemia-specific assessments should be taken to select the most proper tyrosine kinase inhibitors treatment. Given the excellent survival outcomes achieved with long-term tyrosine kinase inhibitor treatment, there is an increasing number of patients who might experience adverse events of different kind or severity, which often results in patients ending up in different, nonhematological medical situations. The description of the most frequently observed complications in connection with a detailed cross-sectional analysis of our own patient cohort is also presented here resembling everyday clinical practice. It is very important that practitioners of other medical professions (general practitioner, internist, cardiologist, angiologist, diabetologist, pulmonologist, gastroenterologist, etc.) should be aware of the possible side effects of specific tyrosine kinase inhibitor therapies. They can help to assist the clinical hematologist in planning the appropriate tyrosine kinase inhibitor therapy as well as in professional caretaking of these patients. Orv Hetil. 2021; 162(30): 1198-1207.
Publication Date: 2021-07-26
Journal: Orvosi hetilap

DNA index as prognostic factor in childhood acute lymphoblastic leukemia in the COG-TARGET database.
This study was aimed to evaluate the value of DNA index(DI) among pediatric acute lymphoblastic leukemia (ALL) treated on Children's Oncology Group (COG) protocols between 2000 and 2015. Retrospective study were analysis among pediatric ALL patients from the TARGET dataset. Totally, 1668 eligible pediatric patients were enrolled in this study. Of them, 993 are male and 675 are female with a median age of 7.6 years old. The median follow-up for those patients was 7.7 years (range 0.1-15.7 years). The probability of 15-year EFS and OS were reported to be 67.5 ± 3.1% and 78.3 ± 2.5%, respectively. BCR/ABL1 fusion gene affected the early treatment response and the survival of childhood ALL. Moreover, those patients with ETV6/RUNX1 fusion gene were also significantly associated with better EFS (HR = 0.6, 95% CI 0.4-0.8, P = 0.003) and OS (HR = 0.3, 95%CI 0.2-0.5, P < 0.001) compared to patients with no ETV6/RUNX1. On the contrary, BM NR on Day+ 29 showed a significant decrease in EFS (HR = 3.1, 95%CI 2.1-4.5, P < 0.001) and OS (HR = 1.7, 95%CI 1.1-2.8, P = 0.026). Multivariate analysis showed that DI was significantly associated with better EFS and OS. The threshold effect of DI on poor outcome was significant after adjusting for potential confounders. The adjusted regression coefficient (Log RR) was 0.7 (95%CI 0.1-3.2, P = 0.597) for DI < 1.1 while 8.8 (95%CI 1.4-56.0, P = 0.021) for DI ≥ 1.2 and 0.0 (95%CI 0.0-0.8, P = 0.041) for 1.1 ≤ DI < 1.2. Generalized additive models revealed that the lowest rates of the adverse outcomes estimated to occur among DI between 1.1 and 1.2. For those childhood ALL treated on COG protocols between 2000 and 2015, ETV6/RUNX1 and BM NR were closely related to the prognosis. Moreover, the DI between 1.1 and 1.2 can serve as a significant cut-point discriminating the risk group, which indicated a favourable prognostic factor.
Publication Date: 2021-07-17
Journal: BMC cancer

Leukemia Cell Lines: In Vitro Models for the Study of Chronic Neutrophilic Leukemia.
Chronic neutrophilic leukemia (CNL) is a rare myeloproliferative neoplasm that is genetically characterized by the absence of both the Philadelphia chromosome and BCR-ABL1 fusion gene and the high prevalence of mutations in the colony-stimulating factor 3 receptor (CSF3R). Additional disease-modifying mutations have been recognized in CNL samples, portraying a distinct mutational landscape. Despite the growing knowledge base on genomic aberrations, further progress could be gained from the availability of representative models of CNL. To address this gap, we screened a large panel of available leukemia cell lines, followed by a detailed mutational investigation with focus on the CNL-associated candidate driver genes. The sister cell lines CNLBC-1 and MOLM-20 were derived from a patient with CNL and carry CNL-typical molecular hallmarks, namely mutations in several genes, such as CSF3R, ASXL1, EZH2, NRAS, and SETBP1. The use of these validated and comprehensively characterized models will benefit the understanding of the pathobiology of CNL and help inform therapeutic strategies.
Publication Date: 2021-06-03
Journal: Current oncology (Toronto, Ont.)

Acute Megakaryoblastic Leukemia Harboring a Subclone Expressing BCR-ABL1 Fusion Gene Product.
Acute myeloid leukemia (AML) with BCR-ABL1, also termed Philadelphia chromosome-positive AML (Ph+ AML), is a rare leukemia subtype classified by the World Health Organization in 2016. The characteristics of Ph+ AML have not been fully identified yet. We herein report a patient with Ph+ AML who phenotypically exhibited megakaryoblastic characteristics, FAB:M7 and harbored a subclone expressing BCR-ABL1 gene fusion products. This case suggests that BCR-ABL1 was acquired as a subclone due to a secondary event that might have occurred late during leukemia evolution. Our findings may aid in deciphering the mechanism underlying Ph+ AML development in future studies.
Publication Date: 2021-06-01
Journal: Internal medicine (Tokyo, Japan)

Outgrowth of a CSF3R-mutant clone drives a second myeloproliferative neoplasm in a chronic myeloid leukemia patient: a case report.
Chronic myeloid leukemia (CML) and chronic neutrophilic leukemia (CNL) are two myeloproliferative neoplasms with mutually exclusive diagnostic criteria. A hallmark of CML is the Philadelphia chromosome (Ph), which results in a BCR-ABL1 fusion gene and constitutive tyrosine kinase activity. CNL is a Ph-negative neoplasm and is defined in part by the presence of CSF3R mutations, which drive constative JAK/STAT signaling. Here, we report the exceedingly rare co-occurrence of two granulocytic myeloproliferative neoplasms in a 69-year old male patient. After an initial diagnosis of chronic myeloid leukemia, the patient's clinical course was shaped by hematologic toxicity, the emergence of treatment-resistant BCR-ABL1 clones, and the expansion of a CSF3R-mutant clone without ABL1 mutations under selective pressure from tyrosine kinase inhibitors. The emergence of the CSF3R-mutant, neutrophilic clone led to the diagnosis of CNL as a second myeloproliferative neoplasm in the same patient. This is the first reported case of CNL arising subsequent to CML, which occurred under selective pressure from targeted therapy in a patient with complex clonal architecture. Patients with such molecularly complex disease may ultimately benefit from combination therapy that targets multiple oncogenic pathways.
Publication Date: 2021-02-01
Journal: Biomarker research

Low absolute neutrophil count during induction therapy is an adverse prognostic factor in childhood acute lymphoblastic leukaemia.
Variation in normal blood cells during chemotherapy has not been recognised as a risk factor guiding chemotherapy in childhood acute lymphoblastic leukaemia (ALL). This study aims to explore whether variations in normal haematopoiesis determine prognosis as well as to improve risk-stratified treatment in childhood ALL. A retrospective study of 279 cases of ALL treated with the CCCG-ALL-2015 regimen in the Division of Pediatric Blood Diseases Center, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, from May 2015 to January 2017 was performed to analyse the prognostic impact of blood cell levels on day 19 of induction therapy by Kaplan-Meier method. Patients with childhood ALL with absolute neutrophil count (ANC) ≤ 90 cells/μl, absolute monocyte count (AMC) ≤ 10 cells/μl or absolute lymphocyte count (ALC) ≤ 1000 cells/μl on day 19 of induction therapy had a lower event-free survival (EFS) rate than those with higher values (all P < 0.05). Multivariate analysis confirmed that ANC ≤ 90 cells/μl and ALC ≤ 1000 cells/μl were independent adverse prognostic factors (HR = 1.981 and 2.162, respectively, both P < 0.05). Among patients with minimal residual disease (MRD) < 1% on day 19 of induction therapy, those with ANC ≤ 90 cells/μl had lower EFS than those with ANC > 90 cells/μl (70.8 ± 6.1% vs 86.4 ± 3.1%, P = 0.001). In the subgroup with the BCR/ABL1 fusion gene, patients with ANC ≤ 90 cells/μl on day 19 of induction therapy also had lower EFS than those with ANC > 90 cells/μl (34.4 ± 25.2% vs 25.0 ± 21.7%, P = 0.041). ANC and ALC during induction therapy are independent prognostic factors for childhood ALL. ANC contributes to guiding the prognosis of patients with low-level MRD or the BCR/ABL1 fusion gene.
Publication Date: 2021-01-15
Journal: Annals of hematology

Highly sensitive fluorescence biosensing of BCR-ABL1 fusion gene based on exponential transcription-triggered hemin catalysis.
Simple, sensitive and specific detection of the transcription level of BCR-ABL1 mRNA possesses vital clinical significance in diagnosis and treatment of chronic myeloid leukemia (CML). In this study, an innovative fluorescence biosensing methodology has been developed for sensitive and specific detection of BCR-ABL1 mRNA by integrating high-efficiency of exponential transcription and superior catalytic performance of DNA-grafted hemin. Exponential transcription was triggered by BCR-ABL1 mRNA to produce plenty of RNA products. They can specifically hybridize with circular dual-labeled hemin (DLH) probe to dissociate the intramolecular hemin dimmers into highly active hemin monomers for catalyzing fluorescence substrate tyramine. This exponential transcription-triggered hemin catalysis (ET-HC) strategy showed highly sensitive and specific for BCR-ABL1 detection with a limit of detection at 0.5 aM and a good linear range from 2 aM to 200 fM. This method was successfully applied to directly detect as low as 0.001% e13a2 transcript isoforms from complex genomic RNA extraction. Compared with clinical routine, the overall process is a thermostatic reaction and eliminates additional reverse transcription operation. Therefore, the developed ET-HC strategy might provide a promising alternative tool for precise diagnosis and personalized treatment of CML.
Publication Date: 2021-01-01
Journal: Talanta

Role of BCR-ABL1 isoforms on the prognosis of Philadelphia chromosome positive acute lymphoblastic leukemia in the tyrosine kinase inhibitor era: A meta-analysis.
BCR-ABL1 fusion gene is the driver mutation of Philadelphia chromosome positive acute lymphoblastic leukemia (Ph+ ALL). Although the prognostic value of BCR-ABL1 isoforms in Ph+ ALL patients has been investigated in numerous studies in the tyrosine kinase inhibitor (TKI) era, the results were still conflicting. Hence we performed herein the meta-analysis to comprehensively assess the impact of BCR-ABL1 isoforms on the clinical outcomes of Ph+ ALL patients. Systematic literature review was conducted in PubMed, Embase, and Cochrane databases with the data access date up to June 15, 2020. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated with fixed-effects or random-effects models. Furthermore, subgroup analyses were performed to assess the robustness of the associations. Nine studies with a total number of 1582 patients were eligible for this meta-analysis. Combined HRs suggested that p210 was slightly associated with inferior event-free survival (EFS) (HR = 1.34, 95% CI 1.05-1.72). The overall survival (OS) was not significantly affected (HR = 1.15, 95% CI 0.92-1.45). In subgroup analyses, the HRs showed a trend toward adverse impact of p210 on clinical outcomes. However, the confidence intervals were not crossing the null value only in a minority of subgroups including Caucasian studies, first-generation TKI treated cohort and transplant cohort. Our findings suggested that p210 might pose a mild adverse impact on the EFS of Ph+ ALL patients. This effect might be compromised by the use of second- or third-generation TKIs. Further studies are needed to verify our conclusions.
Publication Date: 2020-12-19
Journal: PloS one

Pathogenic variants causing ABL1 malformation syndrome cluster in a myristoyl-binding pocket and increase tyrosine kinase activity.
ABL1 is a proto-oncogene encoding a nonreceptor tyrosine kinase, best known in the somatic BCR-ABL fusion gene associated with chronic myeloid leukaemia. Recently, germline missense variants in ABL1 have been found to cause an autosomal dominant developmental syndrome with congenital heart disease, skeletal malformations and characteristic facies. Here, we describe a series of six new unrelated individuals with heterozygous missense variants in ABL1 (including four novel variants) identified via whole exome sequencing. All the affected individuals in this series recapitulate the phenotype of the ABL1 developmental syndrome and additionally we affirm that hearing impairment is a common feature of the condition. Four of the variants cluster in the myristoyl-binding pocket of ABL1, a region critical for auto-inhibitory regulation of the kinase domain. Bio-informatic analysis of transcript-wide conservation and germline/somatic variation reveals that this pocket region is subject to high missense constraint and evolutionary conservation. Functional work to investigate ABL1 kinase activity in vitro by transient transfection of HEK293T cells with variant ABL1 plasmid constructs revealed increased phosphorylation of ABL1-specific substrates compared to wild-type. The increased tyrosine kinase activity was suppressed by imatinib treatment. This case series of six new patients with germline heterozygous ABL1 missense variants further delineates the phenotypic spectrum of this condition and recognises microcephaly as a common finding. Our analysis supports an ABL1 gain-of-function mechanism due to loss of auto-inhibition, and demonstrates the potential for pharmacological inhibition using imatinib.
Publication Date: 2020-11-24
Journal: European journal of human genetics : EJHG

Effect of Dasatinib on Genes Related to Mitotic Catastrophe Pathway in Chronic Myeloid Leukemia Cells.
Chronic Myeloid Leukemia (CML) is characterized by a reciprocal translocation t(9;22) and forms BCR/ABL1 fusion gene called the Philadelphia chromosome. The therapeutic targets for CML patients mediated with BCR/ABL1 oncogenic are tyrosine kinase inhibitors such as imatinib, dasatinib, and nilotinib. The latter two of which have been approved for the treatment of imatinib-resistant or intolerance CML patients. Mitotic Catastrophe (MC) is one of the non-apoptotic mechanisms initiated in types of cancer cells in response to anti-cancer therapies. Pharmacological inhibitors of G2 checkpoint members or genetic suppression of PLK1, PLK2, ATR, ATM, CHK1, and CHK2 can trigger DNA-damage-stimulated mitotic catastrophe. PLK1 and AURKA/B are anomalously expressed in CML cells, where phosphorylation and activation of PLK1 occur by AURKB at centromeres and kinetochores. The purpose of this study is to investigate the effect of dasatinib on the expression of genes in MC and apoptosis pathways in K562 cells. Total RNA was isolated from K-562 cells treated with the IC The array-data demonstrated that dasatinib-treated K562 cells significantly caused the decrease of several genes (AURKA, AURKB, PLK, CHEK1, MYC, XPC, BCL2, and XRCC2). The evidence supplies a basis to support clinical researches for the suppression of oncogenes such as PLKs with AURKs in the treatment of types of cancer, especially chronic myeloid leukemia.
Publication Date: 2020-11-07
Journal: Anti-cancer agents in medicinal chemistry

Chronic Myeloid Leukemia, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology.
Chronic myeloid leukemia (CML) is defined by the presence of Philadelphia chromosome (Ph) which results from a reciprocal translocation between chromosomes 9 and 22 [t(9;22] that gives rise to a BCR-ABL1 fusion gene. CML occurs in 3 different phases (chronic, accelerated, and blast phase) and is usually diagnosed in the chronic phase. Tyrosine kinase inhibitor therapy is a highly effective first-line treatment option for all patients with newly diagnosed chronic phase CML. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with chronic phase CML.
Publication Date: 2020-10-07
Journal: Journal of the National Comprehensive Cancer Network : JNCCN

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

Prolonged Survival of a Patient with Chronic Myeloid Leukemia in Accelerated Phase with Recurrent Isolated Central Nervous System Blast Crisis.
BACKGROUND Chronic myeloid leukemia (CML) is usually a tri-phasic myeloproliferative neoplasm, characterized by the presence of the BCR-ABL1 fusion gene, derived from a balanced translocation, t(9;22)(q34;q11). BCR-ABL tyrosine kinase inhibitors (TKI) are used to treat patients with CML. The addition of pegylated interferon-alpha2b to imatinib or dasatinib results in promising deep molecular responses. Because imatinib shows poor penetration into the central nervous system (CNS), the CNS may become a sanctuary site in patients on prolonged imatinib therapy for CML. It is extremely rare for the blast phase in patients with chronic phase CML to affect the CNS without concomitant bone marrow involvement. CASE REPORT This report describes a 57-year-old woman who was diagnosed with accelerated phase (AP) CML and failed high dose imatinib therapy. Despite achieving an excellent molecular response to dasatinib in 6 months, she developed recurrent isolated CNS blast crisis. Survival was prolonged after treatment with intrathecal chemotherapy and whole-brain radiation therapy combined with dasatinib. After achieving long and deep molecular remission with dasatinib and a few months of pegylated interferon-alpha2a, she lived for 18 months in treatment-free-remission (TFR). At age 65 years, she died of progressive rectal carcinoma with septic shock, cancer-related venous thromboembolism, and a possible autoimmune disorder. CONCLUSIONS This patient with accelerated phase CML and 2 isolated CNS blast crises died in TFR 8.5 years after her initial diagnosis and 7.5 years after her first isolated CNS blast crisis. Survival resulted from tailoring of therapies around her comorbidities.
Publication Date: 2020-09-14
Journal: The American journal of case reports

Myeloid/Lymphoid Neoplasms with Eosinophilia and TK Fusion Genes, Version 3.2021, NCCN Clinical Practice Guidelines in Oncology.
Eosinophilic disorders and related syndromes represent a heterogeneous group of neoplastic and nonneoplastic conditions, characterized by more eosinophils in the peripheral blood, and may involve eosinophil-induced organ damage. In the WHO classification of myeloid and lymphoid neoplasms, eosinophilic disorders characterized by dysregulated tyrosine kinase (TK) fusion genes are recognized as a new category termed, myeloid/lymphoid neoplasms with eosinophilia and rearrangement of PDGFRA, PDGFRB or FGFR1 or with PCM1-JAK2. In addition to these aforementioned TK fusion genes, rearrangements involving FLT3 and ABL1 genes have also been described. These new NCCN Guidelines include recommendations for the diagnosis, staging, and treatment of any one of the myeloid/lymphoid neoplasms with eosinophilia (MLN-Eo) and a TK fusion gene included in the 2017 WHO Classification, as well as MLN-Eo and a FLT3 or ABL1 rearrangement.
Publication Date: 2020-09-05
Journal: Journal of the National Comprehensive Cancer Network : JNCCN

Recurrent Fusion of the GRB2 Associated Binding Protein 1 (
Fusions of the ABL proto-oncogene 1 gene (ABL1 in 9q34) are common in leukemias but rare in solid tumors. The most notable is the t(9;22)(q34;q11)/BCR-ABL1 coding for a chimeric tyrosine kinase. We herein report an ABL1-fusion in a pediatric tumor. G-banding, fluorescence in situ hybridization, reverse transcription polymerase chain reaction and Sanger sequencing were performed on a soft tissue perineurioma found in the left musculus erector spinae of a child. A der(4)t(4;9)(q31;q34) and a fusion of the GRB2 associated binding protein 1 (GAB1 in 4q31) gene with ABL1 were found. A literature search revealed 3 more cases with similar genetic and clinicopathological characteristics: a soft tissue perineurioma with t(2;9;4)(p23;q34;q31) and ABL1 rearrangement, a soft tissue angiofibroma with a GAB1-ABL1 chimeric gene, and a solitary fibrous tumor carrying a der(4)t(4;9)(q31.1;q34). GAB1-ABL1 is a recurrent fusion gene in benign pediatric tumors.
Publication Date: 2020-08-30
Journal: Cancer genomics & proteomics

The impacts of BCR-ABL1 mutations in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia who underwent allogeneic hematopoietic cell transplantation.
The prognostic impacts of BCR-ABL1 fusion gene mutations in Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL) remain unknown. Using data from a nationwide Japanese registry, we have evaluated the prognostic impact of BCR-ABL1 mutations prior to the first allogeneic hematopoietic cell transplantation (HCT). The cohort included 289 patients with a median of 48 years of age (range: 16-70). Point mutations were detected in 110 patients. Of these, 90 (82%) harbored T315I mutations, while 20 had other mutations. With a median follow-up period of 29 months (range: 1-125), outcomes after 2 years were worse with mutations than without (overall survival [OS]: 34% vs 68%, p < 0.001; relapse rate [RR]: 48% vs 18%, p < 0.001), particularly with the presence of the T315I mutation (OS: 29% vs 68%, p < 0.001; RR: 54% vs 18%, p < 0.001). OS was significantly worse in the T315I group even among the cohort with hematological (p < 0.001) or molecular complete remission (p = 0.025) as compared to the no mutation group. Multivariate analysis determined the prognostic impact of the T315I mutation (OS: hazard ratio [HR] = 2.19, 95% confidence interval [CI]: 1.5-3.3, p < 0.001; RR: HR = 2.51, 95% CI: 1.5-4.2, p < 0.001). This study is the first to report on the prognostic significance of BCR-ABL1 mutations in Ph + ALL.
Publication Date: 2020-08-18
Journal: Annals of hematology

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

breakpoint cluster region(5)

leukaemia cml(6)

abl1 fusion(6)

one case(5)

leukemia t-all(5)

inhibitor tki(5)

crisis bc(4)

gene bcr-abl1(4)

etv6-runx1 tcf3-pbx1(3)

q34 q32(2)

1 case(2)