Cytogenetic Studies of B-cell Chronic Lymphocytic Leukemia (B-CLL)

B 细胞慢性淋巴细胞白血病 (B-CLL) 的细胞遗传学研究

• 批准号: 8554041
• 负责人: diane c arthur
• 金额: $ 10.3万
• 依托单位: DIVISION OF CLINICAL SCIENCES - NCI
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8554041
• 关键词: 11q; 13q; 14q32; 17p; Abnormal Cell; Address; B-Lymphocytes; Blood Cells; Chromosomal Loss; Chromosome abnormality; Chronic Lymphocytic Leukemia; Clinical; Correlative Study; Cytogenetics; DNA; DNA Sequence Rearrangement; Data; Detection; Diagnosis; Disease; Disease Outcome; Evaluation; Fluorescent in Situ Hybridization; Frequencies; G-Banding; Gene Expression; In Vitro; Interphase; Karyotype; Laboratories; Leukemic Cell; Lipopolysaccharides; Metaphase; Microarray Analysis; Mitogens; Mitotic; Molecular Cytogenetics; National Heart, Lung, and Blood Institute; Outcome; Patients; Prospective Studies; Quality Control; Reporting; Risk; Series; Specificity; Techniques; Technology; Testing; Time; Treatment Protocols; Trisomy 12; Variant; base; cDNA Arrays; comparative genomic hybridization; disease characteristic; prognostic; response

Previous G-banded karyotype analyses detected clonal chromosome abnormalities in 40-100 percent of B-CLL patients studied after appropriate in-vitro stimulation with polyclonal B-cell mitogens. It was unknown whether the wide variations in frequencies of abnormalities reported in different series were due to true differences in disease characteristics or merely to in-vitro culture conditions. Common recurring chromosomal abnormalities included trisomy 12, rearrangements of 14q32, translocations or deletions of 13q, deletions of 6q, and deletions of 11q. Recent studies have shown increased detection of trisomy 12, 13q deletions, 11q deletions, and 17p (p53) deletions with interphase fluorescence in-situ hybridization (FISH) techniques, suggesting these changes do indeed occur early in the course of the disease. Data regarding the clinical and prognostic significance of cytogenetics in B-CLL are emerging. The data suggest certain karyotypic and/or FISH abnormalities are associated with specific clinicopathologic subsets of B-CLL, and with the course of the disease.To address the questions of timing of karyotypic changes in B-CLL, and the possible specificity and significance of these changes, we have been conducting prospective studies of patients with sporadic or familial B-CLL referred to the NCI and NHLBI for evaluation and possible treatment. The cytogenetics specific aims of this project are: to determine the optimal culture conditions for obtaining karyotypically abnormal mitotic cells from peripheral blood of patients with B-CLL; to determine whether or not interphase FISH detects clonally abnormal cells missed by G-banded metaphase analysis; to determine whether or not comparative genomic hybridization (CGH) will detect gains or losses of chromosomal material not found by metaphase or FISH analyses; and to correlate cytogenetics results with clinical, morphologic and immunophenotypic features of the disease, with cDNA microarray analysis of gene expression, and with outcome with new therapies. More than 250 patients have been entered on-study to date. Our initial analyses from 1997-2004 revealed clonal chromosome abnormalities in only 30-40 percent of cases using G-banded metaphase analysis, and demonstrated inferiority of e. coli lipopolysaccharide as a mitogen for the leukemic cells. Interphase FISH with a panel of five probes has confirmed or expanded the G-band findings in patients with abnormal clones, and has detected abnormalities in all but approximately 10% of patients tested to date. From 2002 through 2005 we performed CGH retrospectively on DNA isolated from patients previously entered on-study, and prospectively on DNA from new patients. CGH was less sensitive than interphase FISH in detecting submicroscopic deletions, but detected gains and losses of regions not probed by FISH. Combining G-banding, FISH, and CGH, we were able to find molecular cytogenetic abnormalities in more than 90% of B-CLL patients; FISH was clearly superior. Furthermore, dual hybridization with two probes and also sequential analyses in multiple patients have shown certain abnormalities present at diagnosis, and additional abnormalities at the time of transformation. Based upon these studies, we are now routinely performing interphase FISH on all patients. We are also quality-controlling new probes for addition to our routine FISH panel. Full G-banded karyotype analysis is done only if specifically indicated. Interphase FISH results are currently being used to classify patients with regard to risk, and in assignment to treatment protocols. Correlative studies of cytogenetics with clinical and other laboratory features at diagnosis and transformation, and with gene expression and response to treatment, are ongoing.

先前的G带核型分析在与多细胞B-cell有丝分裂剂进行了适当的体外刺激后研究的40-100％的B-CLL患者中检测到的克隆染色体异常。 尚不清楚不同系列报道的异常频率的广泛差异是由于疾病特征的真正差异还是仅由于体外培养条件的真正差异。 常见的经常性染色体异常包括第12三体，14q32的重排，13Q的易位或缺失，6q的缺失和11q的缺失。 最近的研究表明，三体缺失，11q缺失和17p（p53）缺失的检测增加，具有相间荧光原位杂交（FISH）技术，这表明这些变化确实发生在疾病的早期。 有关B-CLL中细胞遗传学的临床和预后意义的数据正在出现。 数据表明，某些核型和/或鱼类异常与B-CLL的特定临床病理学子集以及疾病的过程有关。解决B-CLL中核型变化的时间的问题，以及这些变化的可能的特异性和重要性，我们一直在评估孢子或家庭BLLL和NCI nci and nci and nci and nci and nci and nci。 该项目的细胞遗传学特定目的是：确定从B-CLL患者的外周血中获得核型异常有丝分裂细胞的最佳培养条件；为了确定是否通过G带形的中期分析遗漏的克隆异常细胞是否检测到同相；为了确定比较基因组杂交（CGH）是否会检测出中期或鱼类分析未发现的染色体材料的损失；并将细胞遗传学结果与该疾病的临床，形态和免疫表型特征相关联，以及基因表达的cDNA微阵列分析，以及新疗法的结果。 迄今为止，已在研究中已进入250多名患者。 我们从1997年至2004年进行的初步分析显示，使用G带中期分析的病例中只有30-40％的克隆染色体异常，并证明了E的自卑。大肠杆菌脂多糖作为白血病细胞的有丝分裂原。 带有五个探针面板的相间鱼已经证实或扩大了异常克隆患者的G波段发现，并且在迄今已接受测试的患者中，除了大约10％的患者外，均发现异常。 从2002年到2005年，我们对先前进入研究的患者分离的DNA进行了回顾性的CGH，并对新患者的DNA进行了前瞻性。 CGH在检测亚显微镜缺失方面的敏感性不如相互相互作用，但发现未被鱼类探索的区域的收益和损失。 结合G带，鱼和CGH，我们能够在90％以上的B-CLL患者中找到分子细胞遗传学异常。鱼显然是优越的。 此外，与两个探针的双重杂交以及多个患者的顺序分析表明，诊断时存在某些异常，并且在转化时有其他异常。 基于这些研究，我们现在正常对所有患者进行相间鱼类。 我们还在质量控制的新探针中，以增加常规鱼板。 全G带核型分析仅在明确指示时才进行。 当前，相间鱼类的结果用于对患者进行风险和分配治疗方案的分类。 诊断和转化时的细胞遗传学与临床和其他实验室特征以及基因表达和对治疗的反应的相关研究正在进行中。