慢性粒细胞白血病对BCR-ABL酪氨酸激酶靶向抑制剂的耐药机制

BCR-ABL酪氨酸激酶抑制剂靶向治疗慢性粒细胞白血病（chronic myeloid leukemia, CML)能够达到良好的临床效应,然而随着其临床广泛应用,对其产生耐药逐渐增多。CML细胞多药耐药是目前导致化疗失败,缓解率降低,疾病复发的主要原因。本文就CML对BCR-ABL酪氨酸激酶靶向抑制剂耐药的主要机制进行了阐述。     

Do we need more drugs for chronic myeloid leukemia?

The introduction of protein tyrosine kinase inhibitors (TKIs) in 1998 transformed the management of chronic myeloid leukemia (CML), leading to significantly reduced mortality and improved 5 year survival rates. However, the CML community is faced with several clinical issues that need to be addressed. Ten to 15% of CML patients are diagnosed in advanced phase, and small numbers of chronic phase (CP) cases experience disease progression each year during treatment. For these patients, TKIs induce only transient responses and alternative treatment strategies are urgently required. Depending on choice of first line TKI, approximately 30% of CML CP cases show suboptimal responses, due to a combination of poor compliance, drug intolerance, and drug resistance, with approximately 50% of TKI-resistance caused by kinase domain mutations and the remainder due to unknown mechanisms. Finally, the chance of successful treatment discontinuation is on the order of only 10–20% related to disease persistence. Disease persistence is a poorly understood phenomenon; all CML patients have functional Philadelphia positive (Ph+) stem and progenitor cells in their bone marrows and continue to express BCR-ABL1 by DNA PCR, even when in very deep remission and following treatment discontinuation. What controls the maintenance of these persisting cells, whether it is necessary to fully eradicate the malignant clone to achieve cure, and how that might be approached therapeutically are open questions.     

环氧合酶抑制剂塞来昔布促进酪氨酸激酶抑制剂STI571抗白血病效应的研究

目的：探讨环氧合酶-2(COX-2)抑制剂塞来昔布(celecoxib)促进酪氨酸激酶抑制剂STI571的抗白血病效应及其机制。方法：以不同浓度的celecoxib与STI571组合孵育K562细胞,光镜、荧光显微镜观察细胞形态,MTT比色法观察两者对细胞的生长抑制情况,流式细胞术作DNA倍体分析及细胞凋亡线粒体流式检测,半定量RT-PCR法分析相关基因的表达。结果：(1)Celecoxib可促进STI571抑制白血病细胞增殖的能力,0.25μmol/LSTI571与40.0、60.0μmol/L的celecoxib联用抑制率分别为76.1%±1.6％、91.5%±0.4％,明显高于单药组60.0%±2.0％(0.25μmol/LSTI571)、34.7%±0.5％(40.0μmol/Lcelecoxib)、49.8%±1.8％(60.0μmol/Lcelecoxib)(P0.05)。结论：单用celecoxib仅抑制K562细胞增殖,而联用STI571可明显降低K562细胞对STI571的效应阈值,促进STI571诱导的增殖抑制和凋亡。     

伴CSF3RT618I突变的慢性粒单核细胞白血病1例并文献复习

目的：提高对伴CSF3RT618I突变的慢性粒单核细胞白血病(chronic myelomonocytic leukemia, CMML)的认识。方法：分析1例伴CSF3RT618I突变的CMML,结合文献复习讨论。结果：我们首次在CMML中报道CSF3RT618I突变。CSF3R突变的患者预后较差,酪氨酸激酶抑制剂能否改善其预后尚不清楚。结论：CSF3RT618I突变对CMML患者的预后影响还需要进一步临床研究来确定。     

胃癌中酪氨酸激酶抑制剂治疗进展

酪氨酸激酶分子信号通路异常在胃癌发生发展中发挥重要作用.c-met和c-src信号通路的激活、两者相互作用的可能机制与肿瘤血管形成的关系等一系列基础研究结果,以及酪氨酸激酶抑制剂(tyrosine kinase inhibition,TKI)治疗胃癌的初步结论、c-met和c-src相关的TKI耐药机制等,为胃癌的个体...     

恶性血液病8号染色体数目异常的间期荧光原位杂交检测

目的　探讨间期荧光原位杂交 (fluorescenceinsituhybridization ,FISH)技术在检测恶性血液病 8号染色体数目异常中的价值。方法　采用常规细胞遗传学 (conventionalcytogenetics ,CC)和 8号染色体着丝粒特异性探针间期FISH技术对 8例CC检测显示 8号染色体数目异常的急性髓细胞样白血病患者、10例慢性髓细胞样白血病加速期或急变期患者和 3名正常人骨髓进行 8号染色体数目检测。结果9例CC检测为三体 8的患者中 ,FISH检测结果均与其一致 ,其中例 5经CC检测仅发现存在二体 8、三体8和四体 8克隆 ,而FISH检测不但证实了三体 8和四体 8克隆的存在 ,还发现存在一个较小的五体 8克隆。例 3和例 17经CC检测只发现一个细胞有三体 8,无法确定是否为三体 8克隆性畸变 ,FISH检测证实有三体 8克隆存在。例 9经CC检测未发现三体 8,FISH检测发现有三体 8克隆存在。与CC检测结果相比 ,除例 16三体 8检出率FISH结果明显高于CC检测结果外 ,其余均低于或接近CC检测结果。结论　间期FISH技术对检测 8号染色体数目异常具有重要价值 ,当CC检测正常、不肯定或中期分裂相质量差、数量少时作用更大 ,是CC的重要补充。     

骨髓增生异常/骨髓增殖性肿瘤1例诊治分析

了解骨髓增生异常/骨髓增殖性肿瘤(myelodysplastic/myeloproliferative neoplasms,MDS/MPN)的临床类型、病理特征、基因突变,对其预后进行评估.收集1例MDS/MPN病例及相关参考文献,观察其临床表现、临床病理学特征、基因突变及最终临床分型,判断治疗疗效,并进行预后评价.MDS/MPN同时具有MDS和MPN的临床及主要血液学特点,目前分为慢性粒单细胞白血病、不典型慢性粒细胞白血病,BCR-ABL1阴性(atypical chronic myeloid leukemia,aCML)、幼年型粒单细胞白血病(juvenile myelomonocytic leukemia,JMML)、伴环形铁粒幼细胞和血小板增多的骨髓增生异常/骨髓增殖性肿瘤(MDS/MPN with ring sideroblasts and thrombocytosis,MDS/MPN-RS-T)、MDS/MPN,无法分类(MDS/MPN-unclassifiable,MDS/MPN-U)等5种类型.各型有其不同诊断标准,而上述不同疾病之间出现转化,国内未见报道.保定市第一医院诊治1例最初诊断不明确的慢性髓系恶性肿瘤,随着疾病的演变而最终确诊为慢性粒单细胞白血病.通过本病例表明,在不同类型MDS/MPN之间可能会存在类型转换.     

BCR-ABL kinase domain mutations in tyrosine kinase inhibitors-naïve and -exposed Southeast Asian chronic myeloid leukemia patients

BCR-ABL kinase domain (KD) mutation is the main mechanism associated with resistance to tyrosine kinase inhibitors (TKI) in chronic myeloid leukemia (CML) patients. This study targeted a large cohort of CML (n = 171) comprising 80 naïve CML cases without prior TKI exposure as well as 91 cases undergoing 1st generation (imatinib) and/or 2nd generation (nilotinib/dasatinib) TKI therapy. KD mutations were analyzed by denaturing high performance liquid chromatography followed by direct sequencing. Twenty-one types of mutations were found in 37 patients including 13 known mutations and 8 previously unidentified mutations. Thirty cases had a single mutation while 7 cases had multiple mutations. Twenty-three percent of patients receiving first-line imatinib, 69% of imatinib-resistant patients receiving 2nd generation TKI, and 75% of advanced phase patients treated with front-line 2nd generation TKI had KD mutations. Interestingly, 9% of TKI-naïve CML cases were also discovered to carry the KD mutations including 5 novel variants. Patients who received hydroxyurea had a 2-fold increase in KD mutations as compared to newly diagnosed patients but they still had a lower mutation frequency than TKI-exposed cases. Mutations in the naïve cases were mainly localized in the C-helix domain and SH3 contact site whereas in exposed cases predominantly in the drug contact site, P-loop, and catalytic domain. T315I resistant mutation was identified only in TKI-exposed cases. In conclusion, several known and novel BCR-ABL KD mutations were discovered in the TKI-naïve and -exposed Southeast Asian CML patients, supporting the concept that naturally occurring KD mutations were present in leukemic cells prior to drug exposure. T315I resistant mutation was completely undetectable in this naïve Southeast Asian cohort; its incidence, however, increases with drug exposure.     

提高伊马替尼对慢粒白血病敏感性的方法

随着伊马替尼耐药机制的不断阐明,出现了许多应对耐药的策略.其中提高慢性粒细胞白血病(chronic myeloid leukemia,CML)对伊马替尼敏感性是研究较多的领域,主要方法有提高细胞内伊马替尼的药物浓度、调节信号通道、下调细胞凋亡抑制因子的表达等.     

Identification of Exocytosis Mediator Proteins in Peripheral Blood Neutrophils of Patients with Chronic Myeloid Leukemia

We demonstrated expression of plasma membrane proteins (syntaxin-4 and syntaxin-6) and specific/gelatinase granule membrane proteins (SNAP-25 and VAMP-2) in the peripheral blood neutrophils of patients with chronic myeloid leukemia. VAMP-1 associated with membranes of azurophilic and specific/gelatinase granules was absent in peripheral blood neutrophils of patients with chronic myeloid leukemia. Decreased capacity of neutrophils to exocytosis in chronic myeloid leukemia is probably caused by the absence of VAMP-1 in these cells.     

Clinical evaluation of colony-stimulating factor 1 receptor inhibitors

Signaling through colony-stimulating factor 1 receptor (CSF1R) regulates the development, differentiation, and activation of mononuclear phagocytic cells. Inhibition of this pathway provides an opportunity for therapeutic intervention in diseases in which these cells play a pathogenic role, including cancers, inflammation, fibrosis, and others. Multiple monoclonal antibodies and small molecule inhibitors targeting CSF1R or its known ligands CSF1 and IL-34 have been clinically tested and are generally well tolerated with side effects associated with on-target macrophage inhibition or depletion. To date, clinical activity of CSF1R inhibitors has been primarily observed in diffuse-type tenosynovial giant cell tumors, a disease characterized by genetic alterations in CSF1 leading to dysregulated CSF1R signaling. Expanded development into novel indications such as chronic graft vs host disease may provide new opportunities to further explore areas where a role for CSF1R dependent monocytes and macrophages has been established. This review presents key findings from the clinical development of 12 CSF1/CSF1R targeted therapies as monotherapy or in combination with immune checkpoint inhibitors and chemotherapy.     

Discovery of B cell antigen on blast cells of patients with chronic myeloid leukemia

The presence of a common antigen on B lymphocytes of healthy blood donors and on myeloblasts of patients with chronic myeloid leukemia (CML) in the blast crisis (BC) stage was established with the aid of an antimyeloblast serum by the indirect surface immunofluorescence test. In the cytotoxic test this antigen was found on the blast cells of 27 patients with CML in the BC stage and in three of 11 patients with acute lymphatic leukemia, in one of eight patients with chronic lymphatic leukemia, and in both of two patients with undifferentiated leukemia. No antigen was found on the peripheral blood cells of healthy donors by this test.Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR L. M. Shabad.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 87, No. 6, pp. 574–576, June, 1979.     

荧光原位杂交检测慢性粒细胞白血病

目的 探讨对慢性粒细胞白血病进行荧光原位杂交(fluorescence in situ hybridization,FISH)检测的意义.方法 对158例慢性粒细胞白血病标本采用24 h短期培养法制备染色体,然后应用双色双融合BCR/ABL探针进行FISH检测,部分标本同时采用R显带技术进行染色体核型分析.结果 158例中共检出Ph阳性标本98例,其中69例(70.4%)为典型双色双融合BCR/ABL探针信号模式(1R1G2F),其余29例(29.6%)为3类12种非典型模式.各种非典型信号模式中出现频率较高的依次为:1R1G1F7例(7.1%)、2R1G1F 5例(5.1%)、1R1G2F&1R1G3F 4例(4.1%)、2R2G1F 3例(3.1%).对18例有核型资料的非典型信号的病例分析显示:其中3例特殊信号系由变异Ph易位引起;2例中出现的3个融合信号来源于附加的Ph染色体;4例核型与FISH结果不吻合,提示染色体分析存在错漏之处;3例染色体为典型Ph易位,而FISH结果为单个融合信号,系由der(9)号的部分缺失所致;3例核型中未发现Ph染色体.但FISH显示40%～64%的细胞中存在一个融合信号,从而明确慢性粒细胞白血病诊断;3例是移植或经格列卫治疗后的患者,染色体均为正常核型,而FISH检测到极小比例的阳性细胞.结论 FISH在慢性粒细胞白血病诊断、判断变异易位、隐匿Ph易位、衍生9号缺失、干扰素及格列卫的疗效观察以及移植后监测等诸多方面均具有重要价值.     

Myofibroblast Transformation in Metastatic Extramedullary Chronic Myeloid Leukemia: A Case Report

Primary and metastatic carcinomas have a reactive stroma characterized by many myofibroblasts. These cells have also been documented in nonepithelial malignancies, such as sarcomas, malignant melanoma, and lymphoid tumors but in generally far fewer numbers. In non-Hodgkin's lymphoma, Hodgkin's disease, and leukemia, myofibroblasts are rather rarely documented. In particular, there appear to be no reports of myofibroblasts in either primary bone-marrow/peripheral blood leukemia or secondary deposits of leukemia. In this paper, a case of a relapsed chronic myeloid leukemia appearing in an inguinal lymph node is described, containing many myofibroblasts. The case is detailed and presented with a discussion on the role of myofibroblasts in the progression of nonepithelial cancers.     

慢性粒细胞白血病肿瘤干细胞的免疫调节功能

目的 研究慢性粒细胞白血病(CML)骨髓来源的肿瘤干细胞的免疫学特征,比较其与正常人来源的间充质干细胞(MSC)是否存在免疫功能的异常.方法 分离正常人和CML患者骨髓中的MSC,MLR法检测其对T细胞增殖的影响,流式细胞术检测其对T细胞周期、凋亡的作用情况.结果 CML和正常志愿者骨髓来源的MSC的细胞形态和表型没有差异,CML患者来源的MSC抑制T细胞增殖能力和抑制T细胞停留在G0/G1期的作用均减弱(CML MSC组74.5%±1.2%,BMSC组94.0%±1.9%,P＜0.05),CML患者抑制T细胞凋亡的作用增强(CMLMSC组8.36%±1.31%,BMSC组14.10%±0.65%,P＜0.05).结论 CML患者骨髓来源的MSC存在明显的免疫调节功能缺陷,如果使用CML患者自体的MSC移植治疗可能不是一种很好的选择,对于CML患者最好是选用异基因的MSC移植.