Retrospective validation of putative breast cancer predictive molecular markers

描述(申请人提供)：尽管近年来浸润性乳腺癌的死亡率略有下降，但它仍然是美国女性被诊断为癌症最多的癌症和第二大癌症死亡原因。如果癌症在癌前阶段被发现和治疗，我们可以预期死亡率会显著降低。然而，目前还没有已知的标记物来检测癌前阶段或预测哪些癌前病变会发展成IBC。我们最近通过对有和没有癌症病史的患者的癌前病变的全球基因表达分析，确定了300多个可能的乳腺癌预测分子标记物。然而，目前尚不清楚300个假定标记物中的哪一个可以用于检测真正的癌前阶段并预测癌症的发展，除非它们得到验证。我们的长期目标是通过在癌前阶段进行检测来降低乳腺癌的死亡率。这项申请的目的是确定至少三个假定的标记物可以作为乳腺癌预测标记物。我们确定的推定标记物可以作为预测标记物的理由是基于我们使用有限数量的癌前病变档案获得的初步数据。我们的数据表明，三个可能的标记物在后来发展为癌症的患者的癌前组织中高度表达，而在对照组中缺失。我们将通过追求两个特定的目标来实现这项应用的目标：1)利用癌前档案组织和免疫组织化学方法，确定至少三个假定标记物的高表达与癌症的后续发展相关；2)通过RT-Real-time PCR，在大多数不典型细胞和通过导管灌洗收集程序获得的小部分良性细胞中，建立有效的标记物的mRNA水平。拟议工作的基本原理是：1)一旦我们确定预测标记物的高表达与乳腺癌的后续发展有关，这些信息就可以用于筛查癌前病变和识别有可能发展为癌症的病变的患者，以及2)验证的标记物可以用于使用通过导管灌洗收集等程序获得的导管细胞样本来筛查没有病变的妇女，并确定那些癌症发展的高危人群。这项拟议的工作是创新的，因为对癌症发展的预测将基于一组分子标志物的表达，而不是癌前病变的组织诊断。它利用了我们确定的可能的乳腺癌标记物，据我们所知，其他任何人都没有做到这一点。我们期望这些可能的分子标志物的高表达将预测癌症的发展，并且这些分子可以通过RT-Real-time PCR在导管灌洗液中检测到。结果将是重要的，因为预计新知识可以应用于在乳房X光检查可检测到或可触摸到的肿瘤形成之前的癌症前期阶段检测癌症。癌前阶段的发现和治疗将对减少癌症死亡产生重大影响，同时降低医疗成本。目前的项目是在有乳房X光检查可检测到的良性病变的女性以及没有乳房X光检查可检测到的病变的女性中，识别出检测到癌前阶段并预测乳腺癌发展的标志物。在癌前阶段进行检测和治疗可能会降低乳腺癌的发病率和死亡率。

DESCRIPTION (provided by applicant): Although there is a slight decline in the deaths from invasive breast cancer in recent years, it continues to be the most diagnosed cancer and the second leading cause of cancer deaths for women in the US. We can expect a significant reduction in the death rate if the cancer is detected and treated at the precancerous stage. However, there are no known markers to detect a precancerous stage or predict which precancerous lesions will develop into IBC. We recently identified over 300 putative breast cancer predictive molecular markers by global gene expression analysis of precancerous lesions from patients with and without the history of cancer. However, it is not known which of the 300 putative markers could be applied for detecting a 'True Precancerous Stage' and predicting cancer development unless they are validated. Our long range goal is to reduce mortality rate with breast cancer, by detecting at the precancerous stage. The objective of this application is to establish that at least three of the putative markers could be applied as breast cancer predictive markers. Our rationale that the putative markers that were identified by us could be applied as predictive markers was based on our preliminary data obtained using limited number of archival precancerous lesions. Our data suggested that three of the putative markers were highly expressed in precancerous tissues from patients who later developed cancer and were absent in the control group. We will accomplish the objective of this application by pursuing two specific aims: 1) Establish that elevated expression of at least three putative markers is associated with subsequent development of cancer using archival precancerous tissues and by immunohistochemistry, 2) Establish that the validated markers could be detected at their mRNA levels in mostly atypical cells and a small percentage of benign cells obtained by ductal lavage collection procedure by RT real-time PCR. The rationale for the proposed work is that 1) once we establish that elevated expression of the predictive markers is associated with subsequent development of breast cancer, that information could be used for screening precancerous lesions and identifying patients with lesions that may develop into cancer, and 2) the validated markers could be used for screening women with no lesions using samples of ductal cells obtained by procedures such as ductal lavage collection and identifying those at very high risk of cancer development. The proposed work is innovative, because predictions on cancer development will be based on the expression of a group of molecular markers instead of histological diagnosis of precancerous lesions. It capitalizes on the putative breast cancer markers identified by us which to our knowledge not done by any one else. It is our expectation that elevated expression of the putative molecular markers will predict cancer development and those molecules could be detected in ductal lavage by RT real-time PCR. The outcomes will be significant, because it is expected that the new knowledge could be applied to detect cancer at the precancerous stage before mammographically detectable or palpable tumor are formed. Detection and treatment at the precancerous stage will have a major impact in reducing the deaths from cancer, simultaneously cutting down the health care cost. The current project is to identify markers that detect a pre-cancerous stage and predict development of breast cancer in women who have mammographically detectable benign lesions as well as in women who have no mammographically detectable lesions. Detection at the precancerous stage and treatment could lead to fewer incidences of breast cancer and deaths from it.