CTCL STAGING USING GENE EXPRESSION PROFILES

皮肤t细胞淋巴瘤（CTCL），包括蕈样真菌病（MF）和Sezary综合征（SS），是分阶段进展的惰性淋巴瘤，从皮肤病变开始，有时经过循环肿瘤细胞的白血病期，最终扩散到内脏器官。即使对于疾病程度相似的患者，CTCL的治疗效果也不尽相同，这强调了可能存在无法检测到的异质性。这些特征加上大量患者样本档案的可用性，使其成为通过分子谱进行肿瘤分期的良好候选者。SS， CTCL的白血病形式将是这些研究的最初重点，因为它提供了大量纯化恶性细胞的容易途径。来自10名患者的RNA，具有不同的疾病表现和进展模式，将在第一年使用cDNA探针阵列分析20,000序列验证的Unigene簇，以确定这些细胞的整体基因表达模式。样本将从新诊断的SS患者和存活的冷冻SS细胞档案中选择，包括在超过10年的疾病进展阶段收集的样本。由于CTCL细胞代表Th-2 t细胞，来自健康供体PBL的RNA被刺激形成Th-2表型将被用作对照。与对照组相比，患者rna中过度表达或表达不足的基因将成为减少的基因组的候选肿瘤标记物，用于筛选更大的患者样本组。在研究的第二阶段，将选择100名患者进行基因表达研究，减少到1000-2000个基因。这些表达谱将使用统计技术进行分析，以确定在患者亚群中以相似方式表现的基因组。这些分析的结果将是一个假定的基因诊断小组，其表达水平描述肿瘤的类别。表达水平与肿瘤组之间的相关性将通过测量基因表达的替代方法得到证实。最后，将来自患者病史的临床信息与按基因表达水平聚类的肿瘤进行比较，以确定是否可以从特定的基因表达模式预测重要的临床结果，例如对治疗的反应性。在进行上述研究的同时，将对MF患者（与皮肤相关的早期CTCL）的样本进行查询，以确定可诊断SS的基因组，以确定相同的基因是否也足以表征不同类型的MF。如果发现新的基因簇，它们将被添加到候选标记的数据库中。如果没有，将对多达10名MF患者进行20,000个基因过滤器的分析，以区分MF和SS患者的表达模式。如果发现，这些将被添加到候选SS基因面板。最后，将开发技术来检测临床环境中的表达谱。

The cutaneous T-cell lymphomas (CTCL) including Mycosis fungoides (MF) and Sezary syndrome (SS) are indolent lymphomas that progress in stages, starting with skin lesions, sometimes proceeding through a leukemic phase with circulating tumor cells and eventually spreading to the visceral organs. Treatments for CTCL vary in efficacy even for patients with what appears to be similar level of disease, emphasizing the likely existence of undetectable heterogeneity. These characteristics added to a the availability of a large archive of patient samples make it a good candidate for tumor staging by molecular profiles. SS, the leukemia form of CTCL will be the initial focus of these studies as it provides easy access to large numbers of purified malignant cells. RNA from 10 patients, with diverse patterns of disease presentation and progression, will be analyzed during the first year against arrays of cDNA probes for 20,000 sequence verified Unigene clusters in order to determine the global gene expression patterns of these cells. Samples will be selected from newly diagnosed SS patients and from an archive of viably frozen SS cells including samples collected at progressive stages of disease over a period of greater than 10 years. Since CTCL cells represent Th-2 T-cells, RNA from healthy donor PBL, stimulated to develop a TH-2 phenotype will be used as controls. Genes that are over or under-expressed in patient RNAs, compared to controls, will be candidate tumor markers for a reduced panel of genes that will be used to screen a larger group of patient samples. In the second phase of the study, 100 patients will be selected for gene expression studies with a reduced panel of 1000-2000 genes. These expression profiles will be analyzed, using statistical techniques, to identify groups of genes that behave in a similar fashion in subsets of patients. The results of these analyses will be a putative diagnostic panel of genes whose expression levels describe classes of tumors. The correlation between expression levels and tumor groups will be confirmed using alternative methods for measuring gene expression. Finally, clinical information from patient histories will be compared with tumors clustered by gene expression levels to determine whether important clinical outcomes, e.g., responsiveness to treatment, can be predicted from the specific gene expression patterns. Concurrent with the above studies, samples from patients with MF, the skin-associated early form of CTCL, will be queried with the panel of genes identified as being diagnostic for SS to determine whether the same genes are also sufficient to characterize different classes of MF. If novel gene clusters are found, they will be added to the data base of candidate markers. If not, up to 10 MF patients will be analyzed on 20,000-gene filters for genes whose expression pattern distinguishes MF from SS patients. If found, these will be added to the panel of candidate SS genes. Finally, techniques will be developed to assay expression profiles in a clinical setting.