Department of Neuroscience and Biomedical Technologies, University of Milan-Bicocca, Monza, Italy.
PLoS One. 2011;6(9):e24237. doi: 10.1371/journal.pone.0024237. Epub 2011 Sep 1.
Bladder carcinogenesis is believed to follow two alternative pathways driven by the loss of chromosome 9 and the gain of chromosome 7, albeit other nonrandom copy number alterations (CNAs) were identified. However, confirmation studies are needed since many aspects of this model remain unclear and considerable heterogeneity among cases has emerged. One of the purposes of this study was to evaluate the performance of a targeted test (UroVysion assay) widely used for the detection of Transitional Cell Carcinoma (TCC) of the bladder, in two different types of material derived from the same tumor. We compared the results of UroVysion test performed on Freshly Isolated interphasic Nuclei (FIN) and on Formalin Fixed Paraffin Embedded (FFPE) tissues from 22 TCCs and we didn't find substantial differences. A second goal was to assess the concordance between array-CGH profiles and the targeted chromosomal profiles of UroVysion assay on an additional set of 10 TCCs, in order to evaluate whether UroVysion is an adequately sensitive method for the identification of selected aneuploidies and nonrandom CNAs in TCCs. Our results confirmed the importance of global genomic screening methods, that is array based CGH, to comprehensively determine the genomic profiles of large series of TCCs tumors. However, this technique has yet some limitations, such as not being able to detect low level mosaicism, or not detecting any change in the number of copies for a kind of compensatory effect due to the presence of high cellular heterogeneity. Thus, it is still advisable to use complementary techniques such as array-CGH and FISH, as the former is able to detect alterations at the genome level not excluding any chromosome, but the latter is able to maintain the individual data at the level of single cells, even if it focuses on few genomic regions.
膀胱癌的发生被认为遵循两种替代途径,一种由 9 号染色体缺失驱动,另一种由 7 号染色体获得驱动,尽管已经确定了其他非随机拷贝数改变(CNAs)。然而,由于该模型的许多方面仍不清楚,并且病例之间出现了相当大的异质性,因此需要确认性研究。本研究的目的之一是评估广泛用于检测膀胱癌的靶向测试(UroVysion 检测)在两种源自同一肿瘤的不同类型材料中的性能。我们比较了在 22 例 TCC 中新鲜分离的间期核(FIN)和福尔马林固定石蜡包埋(FFPE)组织上进行的 UroVysion 试验的结果,并未发现实质性差异。第二个目标是评估在另外 10 例 TCC 中,基于阵列的 CGH 图谱和 UroVysion 检测的靶向染色体图谱之间的一致性,以评估 UroVysion 是否是一种足够敏感的方法,用于鉴定 TCC 中的选定非整倍体和非随机 CNAs。我们的结果证实了基于阵列的 CGH 等全基因组筛选方法的重要性,该方法用于全面确定大型 TCC 肿瘤的基因组图谱。然而,该技术仍存在一些限制,例如无法检测低水平镶嵌性,或者由于存在高细胞异质性而无法检测到某种拷贝数的变化。因此,仍然建议使用互补技术,如基于阵列的 CGH 和 FISH,因为前者能够检测基因组水平的改变,而不排除任何染色体,但后者能够保持单个细胞水平的个体数据,即使它集中在少数基因组区域。