RNA from Brush Cytology to Detect Squamous Cell Carcinoma

描述(申请人提供)：鳞状细胞癌是一种侵袭胃肠道和呼吸道粘膜的癌症，是目前口腔癌的主要形式。矛盾的是，虽然口腔鳞状细胞癌(OSCC)通常始于口腔内的可见病变，但在这个可治愈的阶段早期发现疾病是有限的。这可能是因为发生了大量其他更无害的口腔病变，可能类似于口腔鳞癌，而且有必要进行手术活检，以准确检测和诊断疾病。刷检口腔细胞学可以用来收集可疑病变的细胞，而不需要手术，反过来，这些细胞可以用于恶性病变的显微分析，但准确性降低。我们提出了一种评估病变的方法，该方法使用同样的非侵入性程序，刷检细胞学，但提供RNA以允许对病变粘膜的基因表达进行分析。我们已经证明，这种方法与先入为主的想法相反，它不可行，提供了高质量的RNA，能够在仓鼠口腔癌模型中将口腔鳞癌与正常粘膜区分开来。我们将利用最近在手术活检组织中显示的研究，基于全球基因表达的变化，可以开发出能够准确诊断恶性疾病的类别预测因子。这项拟议的研究将确定是否可以分析细胞学的RNA，以产生可用于检测口腔鳞癌的全球基因表达特征。未来的口腔鳞癌患者，在接受标准的口腔鳞癌活检诊断之前，将接受刷检口腔细胞学，以使我们能够开发并验证识别口腔鳞癌的基因表达特征。一个立竿见影的结果将是一种非侵入性的方法，可以准确地检测并有助于口腔鳞癌的诊断，准备在其他诊所进一步验证。接下来，我们将应用同样的方法来开发一种基于基因表达的分类预测因子，用于早期鳞状细胞癌、中到重度不典型增生和原位癌。在分析了从口腔癌前病变的刷检细胞学中获得的RNA后，我们将使用针对异质样本优化的统计方法，基于一小部分基因的基因表达来开发这些早期恶性肿瘤的类别预测因子。最后，我们将开始确定使用刷检细胞学RNA对口腔癌前病变和口腔鳞癌的检测和诊断是否优于OralCDx系统。1 与公共卫生相关：这些结果应该提供一种非侵入性的方法来检测绝大多数口腔癌，即使是在疾病的早期阶段也是有效的。它将准备在更多的诊所与其他调查人员一起进行测试。这应该可以更早地发现口腔癌，并可以立即挽救生命。这一发现将有力地支持刷检细胞学方法的RNA用于其他胃肠道和呼吸道癌症。这项研究还将确定非侵入性刷检细胞学方法检测口腔癌前病变并提供原型预测指标的可行性。通过一些改进，例如使用商业上可获得的室温RNA稳定溶液，这将使我们更接近一种经济的、非侵入性的口腔癌症筛查形式。

DESCRIPTION (provided by applicant): Squamous cell carcinoma, a cancer which afflicts sites including the gastrointestinal and airway mucosa, is by far the predominant form of oral cancer. Paradoxically, while oral squamous cell carcinoma, OSCC, typically initiates as visible lesions in the oral cavity, early detection of the disease at this curable stage is limited. This is likely due to the high number of other more innocuous oral lesions that occur that can resemble OSCC, and the necessity for a surgical biopsy for accurate detection and diagnosis of the disease. Brush oral cytology can be used to collect cells from suspect lesions without surgery, which in turn can be used for microscopic analysis of malignant changes but with decreased accuracy. We propose a method of lesion evaluation that uses this same noninvasive procedure, brush cytology, but to provide RNA to allow gene expression analysis of the lesion mucosa. We have shown that this methodology, contrary to preconceived ideas that it would not be feasible, provided high quality RNA capable of allowing the differentiation of OSCC from normal mucosa in a hamster oral cancer model. We will take advantage of recent studies that have shown in surgically biopsied tissue that class predictors, based on changes in global gene expression, can be developed that can accurately diagnose malignant disease. The study proposed will determine if RNA from cytology can be analyzed to produce a global gene expression signature that can be used to detect OSCC. Prospective OSCC patients, prior to undergoing standard biopsy diagnosis for OSCC, will be subjected to brush oral cytology to allow us to develop, and then validate, a gene expression signature that identifies OSCC. An immediate result will be a noninvasive methodology to accurately detect and contribute to the diagnosis of OSCC, ready to be further validated in other clinics. Next, we will apply this same approach to develop a gene expression based class predictor for the earliest stage of squamous cell carcinoma, moderate to severe dysplasia and carcinoma in situ. After analysis of RNA from brush cytology from pre-cancerous oral lesions, we will use statistical methodologies optimized for heterogeneous samples to develop a class predictor for these early malignancies based on gene expression of a small set of genes. In the end, we will start to determine if the detection and diagnosis of oral premalignancies and OSCC using RNA from brush cytology is superior to the OralCDx system. 1 PUBLIC HEALTH RELEVANCE: These results should deliver a noninvasive method for detection of the vast majority of oral cancers that is validated against even the earliest stages of the disease. It will be ready to be tested in additional clinics with other investigators. This should allow the earlier detection of oral cancer and could save lives immediately. This finding would strongly support the usage of the RNA from brush cytology approach with other gastrointestinal and airway passage cancers. This study would also determine the feasibility of noninvasive brush cytology methods to detect oral premalignancies and deliver a prototype predictor. With some modifications, such as the usage of commercially available room temperature RNA stabilization solutions, this would bring us much closer to an economical, noninvasive form of oral cancer screening.