Efficacy of Nilotinib versus Imatinib in Philadelphia Positive Patients with Chronic Myeloid Leukemia in Early Chronic Phase Who Have a Warning Molecular Response to Imatinib

Background and Objectives: Chronic myeloid leukemia (CML) accounts for approximately 15% of newly diagnosed cases of leukemia in adults. In this study, the efficacy of nilotinib at 400 mg BID is compared with imatinib at 400 mg BID in CML patients with suboptimal molecular response after at least 12 months of daily dose 400 mg of imatinib therapy. Patients and Methods: This study included a total number of 50 patients, divided into two groups (25 patients each). The first group (Group I): Patients received imatinib at 400 mg BID, second group (Group II): Patients had a suboptimal molecular response to imatinib and received nilotinib at 400 mg BID in early chronic phase. During the two years period of data collection, the primary end included median survival. The secondary end included response rate, type of response, duration of response and progression free survival. Also side effects were recorded. Patients were followed up every month by complete and differential blood counts, liver function test, renal function test and (PCR) every three months for two year. Results: Nilotinib group had significantly higher frequency of major molecular response (MMR) where 23 (92%) patients achieved it while only 16 (64%) patients in Imatinib group achieved MMR (P = 0.01). Nilotinib had better toxicities profile than Imatinib. Conclusion: Both Nilotinib and high dose Imatinib achieved response in CML patients with suboptimal response with rapid and deeper molecular response, better survival outcomes and less side effects in nilotinib.

Frequency of Bcr-Abl Fusion Oncogene Splice Variants Associated with Chronic Myeloid Leukemia (CML)

BCR-ABL fusion oncogene originates from the reciprocal translocation of chromosome 9 and 22 t(9;22) (q34;q11). It translates a chimeric protein, p210, characterized by constitutive activation of its tyrosine kinase, which triggers leukemogenic pathways resulting in onset of chronic myeloid leukemia (CML). In CML, the classic fusion is b2a2 or b3a2 fusing exon 13 (b2) or exon 14 (b3) of BCR to exon 2 (a2) of ABL. The type of bcr/abl transcripts may be associated with different prognosis and hence useful in therapeutic plan. This study was conducted to calculate the frequency of these splice variants as the frequencies of different fusion oncogenes associated with leukaemia can vary in different geographical regions due to interplay of genetic variation in different ethnic populations, diverse environmental factors and living style. A very sensitive nested RT-PCR was established to detect BCR-ABL splice variants in CML. Sensitivity of RT-PCR assay was of the order of 10–6. Thirty CML patients were subjected to BCR-ABL analysis. Out of 30 Pakistani patients, 19 (64%) expressed b3a2 while 11 (36%) expressed b2a2 transcript. This shows that BCR-ABL splice variants differ in their frequencies which may have an effect on biology and implications for prognosis and management of BCR-ABL positive Leukemias.

Coexistence of breakpoint cluster region-Abelson1 rearrangement and Janus kinase 2 V617F mutation in chronic myeloid leukemia: A case report

BACKGROUND The Janus kinase 2(JAK2) V617 F mutation is common in patients with breakpoint cluster region-Abelson1(BCR-ABL1)-negative myeloproliferative neoplasms,including polycythemia vera, essential thrombocythemia and primary myelofibrosis, but is rarely detected in BCR-ABL1-positive chronic myeloid leukemia(CML) patients. Here, we report a CML patient with both a BCR-ABL1 rearrangement and JAK2 V617 F mutation.CASE SUMMARY A 45-year-old Chinese woman was admitted to our department with a history of significant thrombocytosis for 20 d. Color Doppler ultrasound examination showed mild splenomegaly. Bone marrow aspiration revealed a karyotype of 46,XX, t(9;22)(q34;q11.2) in 20/20 metaphases by cytogenetic analysis,rearrangement of BCR-ABL1(32.31%) by fluorescent polymerase chain reaction(PCR) and mutation of JAK2 V617 F(10%) by PCR and Sanger DNA sequencing.The patient was diagnosed with CML and JAK2 V617 F mutation. Following treatment with imatinib for 3 mo, the patient had an optimal response and BCRABL1(IS) was 0.143%, while the mutation rate of JAK2 V617 F rose to 15%.CONCLUSION Emphasis should be placed on the detection of JAK2 mutation when CML is diagnosed to distinguish JAK2 mutation-positive CML and formulate treatment strategies.

Gene Expression Pattern of Signal Transduction in Chronic Myeloid Leukemia

To explore the transcriptional gene expression profiles of signaling pathway in Chronic myeloid leukemia （CML）, a series of cDNA microarray chips were tested. The results showed that differentially expressed genes related to singal transduction in CML were screened out and the genes involved in Phosphoinositide 3-kinases （PI3K）, Ras-MAPK （mitogen-activated protein kinase） and other signaling pathway genes simultaneously. The results also showed that most of these genes were up-expression genes , which suggested that signal transduction be overactivated in CML. Further analysis of these differentially expressed signal transduction genes will be helpful to understand the molecular mechanism of CML and find new targets of treatment.

Predictive indicators of successful tyrosine kinase inhibitor discontinuation in patients with chronic myeloid leukemia

Clinical trials have demonstrated that some patients with chronic myeloid leukemia(CML)treated for several years with tyrosine kinase inhibitors(TKIs)who have maintained a molecular response can successfully discontinue treatment without relapsing.Treatment free remission(TFR)can be reached by approximately 50%of patients who discontinue.Despite having similar levels of deep molecular response and an identical duration of treatment,the factors that influence the successful discontinuation of CML patients remain to be determined.In this review we will explore the factors identified to date that can help predict whether a patient will successfully achieve TFR.We will also discuss the need for the identification of predictive biomarkers associated with a high probability of achieving TFR for the future personalized identification of patients who are suitable for the discontinuation of TKI treatment.

Diagnosis of Chronic Myeloid Leukemia Early in Pregnancy

Imatinib therapy has revolutionized the clinical course of Chronic Myeloid Leukemia. The unexpected prolonged survival raised several issues on the quality of life and on the possibility to parent childs.

P190BCR-ABL Chronic Myeloid Leukemia Following a Course of S-1 Plus Oxaliplatin Therapy for Advanced Gastric Adenocarcinoma

Secondary malignant neoplasms are important late complications after chemotherapy and/or radiotherapy in cancer patients. Therapy-related malignancies include acute leukemia, myelodysplastic syndrome （MDS）, lymphoma, and solid tumors. However, secondary acute lymphoid leukemia or chronic myeloid leukemia （CML） is rarely reported. Here, we present a patient with P190BCR-ABL-positive CML following S-I plus oxaliplatin therapy for gastric adenocarcinoma. The patient has given written informed consent for the use of his medical data.

Tetrandrine citrate eliminates imatinib-resistant chronic myeloid leukemia cells in vitro and in vivo by inhibiting Bcr-Abl/β-catenin axis

Objective:To evaluate the effects of tetrandrine citrate, a novel tetrandrine salt with high water solubility, on the growth of imatinib (IM)-resistant chronic myeloid leukemia (CML) in vitro and in vivo, and reveal action molecular mechanisms. Methods:Cell viability in vitro was measured using methyl thiazolyl tetrazolium (MTT) assay. CML cell growth in vivo was assessed using a xenograft model in nude mice. Bcr-Abl and β-catenin protein levels were determined using Western blotting. Bcr-Abl messenger RNA (mRNA) was measured by reverse transcription polymerase chain reaction (RT-PCR). Flow cytometry (FCM) was used to determine cell cycle status. Results:Tetrandrine citrate inhibited the growth of IM-resistant K562 cells, primary leukemia cells, and primitive CD34 + leukemia cells, and their inhibition concentration that inhibited 50% of target cells (IC 50 ) ranged from 1.20 to 2.97 μg/ml. In contrast, tetrandrine citrate did not affect normal blood cells under the same conditions, and IC 50 values were about 10.12-13.11 μg/ml. Oral administration of tetrandrine citrate caused complete regression of IM-resistant K562 xeno-grafts in nude mice without overt toxicity. Western blot results revealed that treatment of IM-resistant K562 cells with tetrandrine citrate resulted in a significant decrease of both p210 Bcr-Abl and β-catenin proteins, but IM did not affect the Bcr-Abl protein levels. Proteasome inhibitor, MG132, did not prevent tetrandrine-mediated decrease of the p210 Bcr-Abl protein. RT-PCR results showed that tetrandrine treatment caused a decrease of Bcr-Abl mRNA. FCM analysis indicated that tetrandrine induced gap 1 (G 1 ) arrest in CML cells. Conclusions:Tetrandrine citrate is a novel orally active tetrandrine salt with potent anti-tumor activity against IM-resistant K562 cells and CML cells. Tetrandrine citrate-induced growth inhibition of leukemia cells may be involved in the depletion of p210 Bcr-Abl mRNA and β-catenin protein.

BCR-ABL1 is a secondary event after JAK2V617F in a patient with essential thrombocythemia who develop chronic myeloid leukemia

Several cases such as myeloproliferative neoplasms(MPN)with the coexistence of JAK2 and BCR-ABL have been reported.However,cases of transformation of essential thrombocythemia(ET)into chronic myeloid leukemia(CML)during the disease progression were rarely reported.Here,we report the case of a patient with JAK2 V617F-positive ET who subsequently acquired BCR–ABL1,which transformed the disease into CML after 10 years from the initial diagnosis.In this study,we dynamically monitored JAK2 V617F and BCR-ABL and observed multiple gene mutations,including IDH2,IDH1,ASXL1,KRAS,and RUNX1.It is important to be aware of this potentially clone evolution in disease progression.

Effects of Quercetin on Hedgehog Signaling in Chronic Myeloid Leukemia KBM7 Cells

Objective：To investigate the effects of quercetin on Hedgehog（Hh） signaling in chronic myeloid leukemia KBM7 cells.Methods：The KBM7 cells were treated with 50,100 and 200 μmol/L quercetin for48 h respectively.And then the trypan blue assay was used to examine the proliferative inhibition of quercetin.Apoptotic cells and cell cycle were measured by flow cytometry.The mRNA and protein expression were detected by quantitative real-time polymerase chain reaction（PCR） and Western blot,respectively.Results：Quercetin significantly inhibited KBM7 cell proliferation,induced cell apoptosis,and blocked cell cycle at G1 phase,which were in dose-dependent manners.The mRNA and protein expression of Smoothened and Gliomal（Gli1）,the members of Hh pathway decreased after treatment with quercetin.The Bcl-2 and Cyclin D1,targets of Hh signaling,also decreased after treatment with quercetin,respectively.Quercetin also could increase p53 and Caspase-3 expression.Bcr-abl mRNA copies decreased,but no changes of phosphorylated Bcr-abl and Bcr-abl proteins were observed,after treatment with quercetin.Conclusion：Quercetin could inhibit Hh signaling and its downstream targets in the KBM7 cells.And it might be one of mechanisms of inducing apoptosis and inhibiting cell cycle by quercetin.

Characteristics of the TCR Vβ repertoire in imatinib-resistant chronic myeloid leukemia patients with ABL mutations

Diversity in the T cell receptor(TCR) repertoire provides a miniature defense ability for the T cell immune system that may be related to tumor initiation and progression. Understanding the T cell immune status of leukemia patients is critical for establishing specific immunotherapies. Previous studies have reported abnormal TCR repertoires and clonally expanded TCR V? T cells in chronic myeloid leukemia in chronic phase(CP-CML). In this study, we investigated the distribution and clonality of the TCR V? repertoire in 4 cases with imatinib-resistant CML in blast crisis(BC-CML) with abelson murine leukemia viral oncogene homolog 1(ABL1) kinase domain mutations(KDMs). Examination of TCR V? expression and clonality was performed by reverse transcription-polymerase chain reaction(RT-PCR) and Gene Scan analysis. Significantly skewed TCR V? repertoires were observed in BC-CML patients with different KDMs, and 4 to 8 oligoclonally expanded TCR V? subfamilies could be identified in each sample. Intriguingly, a relatively highly expanded V?9 clone with the same length as complementarity-determining region 3(CDR3)(139 bp) was found in all three CML patients in lymphoid blast crisis(LBC-CML) who had different KDMs, but the clone was not detected in the only CML patient in myeloid blast crisis(MBC-CML). In conclusion, restricted TCR V? repertoire expression and decreased clone complexity was a general phenomenon observed in the BC-CML patients with different KDMs, indicating the T-cell immunodeficiency of these patients. In addition, clonally expanded V?9 T cell clones may indicate a specific immune response to leukemia-associated antigens in LBC-CML patients.

Sudden extramedullary and extranodal Philadelphia-positive anaplastic large-cell lymphoma transformation during imatinib treatment for CML:A case report

BACKGROUND Chronic myeloid leukemia(CML)is a malignant hematologic malignancy that can progress to blast phase with a myeloid or lymphoid phenotype.Some patients with CML can also progress to blast crisis phase;however,the transformation of CML into Philadelphia-positive lymphoma is extremely rare.CASE SUMMARY We present a patient with CML who experienced a sudden transformation to anaplastic large-cell lymphoma(ALCL)after 7 mo of treatment with imatinib,during which she had achieved partial cytogenetic response as well as early molecular response.The patient noticed a mass in her left shoulder,the biopsy data of which were consistent with ALCL;moreover,her lymphoma cells exhibited BCR-ABL gene fusion.The patient was diagnosed with Philadelphia-positive ALCL that progressed from CML,and was thus treated with the second generation tyrosine kinase inhibitor nilotinib.Six months later,the mass had totally disappeared and the BCR-ABL fusion gene was undetectable in the peripheral blood.To our knowledge,this is the first patient known to have developed Philadelphia-positive ALCL transformed from CML.CONCLUSION Unexplained lymphadenopathy or an extramedullary mass in a patient with CML may warrant a biopsy and testing for BCR-ABL fusion.

INHIBITION OF APOPTOSIS BY bcr-abl FUSION GENE IN K562 CELLS

Objective: To investigate the effect of bcr-abl fusion gene on CML cell apoptosis. Methods: Apoptosis of ex-vivo cultured K562 cells were observed after exposure to synthetic 18 mer antisense oligodeoxynucleotide complementary to the bcr-abl junction (b3a2). Results: Apoptosis of K562 cells was significantly increased associated with inhibition of bcr-abl expression. Conclusion: bcr-abl fusion gene formation due to chromosome translocation may be the major mechanism of CML via inhibition of apoptosis.

Impact of the Normalized Copy Number of <i>BCR-ABL</i>Transcript upon Diagnosis on Prognosis in CML Patients Treated with Imatinib-Mesylate

Quantification of the BCR-ABL transcript is recommended to follow-up CML patients treated by imatinib mesylate (IM). Results are expressed as a normalized copy number (NCN) of BCR-ABL. We studied a cohort of 98 CML patients under IM as a first treatment and monitored by RQ-PCR after 12, 18 and 24 months according to the European LeukemiaNet recommendations. Our results support the hypothesis of an independent correlation between BCR-ABL NCN at diagnosis and major molecular response at 18 and 24 months in an inverse relationship. We also highlighted the possibility to use the NCN at diagnosis as a warning at diagnosis, and may be useful to identify patients who could benefit of a more rigorous follow-up.

慢性髓系白血病慢性期TKI治疗未达最佳反应或不耐受患者转换氟马替尼的有效性和安全性临床观察

目的 观察TKI未达最佳反应或不耐受的慢性髓系白血病-慢性期(chronic myelogenous leukemia-chronicphase, CML-CP)患者转换氟马替尼治疗的效果及安全性。方法 从重庆市医院及川北医学院附属医院共5家医院收集2020年2月至2022年8月对一线伊马替尼、达沙替尼、尼洛替尼未达最佳反应或不耐受,转换氟马替尼(600 mg/d)治疗的患者,观察氟马替尼的疗效及安全。统计患者治疗3、6、12个月时最佳反应率及主要分子学反应(major molecular response, MMR)率、累积完全细胞遗传学反应(complete cytogenetic response, CCyR)率、累积MMR率、累积深度分子学反应(deep molecular response, DMR)率、无进展生存(progression-free survival, PFS)、无事件生存(event-free survival, EFS)情况及不良反应情况。结果 共纳入100例CML-CP患者,中位随访时间为18(3~36)个月,3、6、12个月最佳反应率分别为92.6%(88/95)、94.4%(85/90)和92.9%(79/85),随访截止至2023年8月20日,累积CCyR、MMR率分别为98.0%(98/100)、81.9%(77/94),达CCyR和MMR的中位时间均为3个月,累积DMR率为51.0%(51/100)。随访时间内,PFS率为100.0%(100/100),1年EFS率为85.6%(75/90)。氟马替尼最常见非血液学不良反应为腹泻腹痛(7.0%),其次为肾功能损害(6.0%)、肌肉骨骼疼痛(2.0%);血液学不良反应主要有血小板减少(12.0%)、贫血(6.0%)和白细胞减少(2.0%)。结论 氟马替尼治疗TKI未达最佳反应或不耐受的CML-CP患者有较好的MMR和DMR,耐受性及安全性良好。

The Philadelphia chromosome in leukemogenesis

The truncated chromosome 22 that results from the reciprocal translocation t(9;22)(q34;q11) is known as the Phila?delphia chromosome(Ph) and is a hallmark of chronic myeloid leukemia(CML).In leukemia cells,Ph not only impairs the physiological signaling pathways but also disrupts genomic stability.This aberrant fusion gene encodes the breakpoint cluster region?proto?oncogene tyrosine?protein kinase(BCR?ABL1) oncogenic protein with persistently enhanced tyrosine kinase activity.The kinase activity is responsible for maintaining proliferation,inhibiting differentia?tion,and conferring resistance to cell death.During the progression of CML from the chronic phase to the accelerated phase and then to the blast phase,the expression patterns of different BCR?ABL1 transcripts vary.Each BCR?ABL1 transcript is present in a distinct leukemia phenotype,which predicts both response to therapy and clinical outcome.Besides CML,the Ph is found in acute lymphoblastic leukemia,acute myeloid leukemia,and mixed?phenotype acute leukemia.Here,we provide an overview of the clinical presentation and cellular biology of different phenotypes of Ph?positive leukemia and highlight key findings regarding leukemogenesis.

Confrontation between Myelogram and Cytogenetics in 35 CML Malagasy Patients

Introduction: Chronic Myeloid Leukemia is a myeloproliferative disorder affecting hematopoietic stem cells. The specific cytogenetic abnormality is translocation (9;22) which leads to the BCR-ABL fusion gene. Methods: We did a bone marrow aspiration in our laboratory of haematology of university hospital Joseph Ravoahangy Andrianavalona Antananarivo. We studied myelogram and compared its result to the cytogenetic result. Results: Men were the most affected by this pathology and diagnostic average age was 51.2 years. Splenomegaly leukocytosis and myelemia were often present. Myelogram showed granulocytic hyperplasia and the t (9;22) were present in all the patients. Conclusion: Diagnosis is based on data from the NFS, the myelogram, the search for the Philadelphia chromosome and BCR-ABL fusion gene. These specialized techniques are still inaccessible for Malagasy patients.

Ph染色体阳性慢性粒细胞白血病的细胞遗传学研究

目的 研究Ph染色体阳性慢性粒细胞白血病即Ph (+ )CML患者的核型状况与病程变化、预后的关系 .方法 采用直接法和短期培养法制备骨髓细胞染色体 ,通过G显带对 198例Ph (+ )CML患者进行染色体核型分析 .结果 ⑴Ph(+ )CML患者中 193例为典型Ph易位 ,占 97.5 %,5例为变异Ph易位 ,占 2 .5 %;⑵急变期超二倍体发生率 (10 .8%)较慢性期 (4.2 %)有显著性差异 (P <0 .0 5 ) ;⑶ 4 1例慢性期患者 (32 .3%)合并额外染色体异常 ,主要异常核型有 19种 ,以 + 8、2个Ph ,-Y较为多见 ;⑷ 2 6例急性期患者 (78.8%)出现额外染色体改变 ,主要异常核型有 2 1种 ,以 2个Ph ,+ 8,i(17q) ,+ 19较多见 ;⑸急变后只有Ph染色体者和同时具有Ph及额外染色体异常者的中位生存期分别为 5 .5月、3.6月 ,二者有显著性差异 (P <0 .0 5 ) .结论 额外染色体畸变的有无及程度与Ph (+ )CML病程进展、预后密切相关 .

节律基因在慢性粒细胞白血病中表达水平及意义

目的探讨节律基因在慢性粒细胞白血病(CML)中的表达情况,及其与bcr/abl融合基因的相关性,为临床治疗提供新的分子靶点。方法收集106例CML患者慢性期、加速期、急变期的骨髓标本和50例健康体检人员的外周血为对照,采用RT-PCR法检测per1、per2、bcr/abl基因表达情况。结果 per1、per2、bcr/abl基因在慢性期、加速期和急变期存在不同水平的变化,并且per1、per2表达水平与bcr/abl基因存在负相关。结论节律基因作为肿瘤抑制因子在CML中是低表达的,在信号转导通路中是否与bcr/abl基因相互作用还需深入研究。