MicroRNAs for monitoring tumor progression and predicting response to therapy

描述（由申请人提供）：背景：MicroRNA（miR）在乳腺肿瘤中发生改变，影响肿瘤的发生和进展。由于miR在循环中非常稳定，它们也具有作为乳腺癌非侵入性生物标志物的巨大潜力。事实上，在乳腺癌患者中已检测到循环miR，但将其解释为微创生物标志物的相关性受到不一致结果的限制。此外，循环miR的细胞来源和调节这些潜在miR生物标志物的分子机制仍不清楚。为了解决这些问题，建立了用于体内研究潜在miR生物标志物的高度相关的动物模型。具有X连锁肿瘤抑制因子Foxp 3（Foxp 3sf/+）的Scurfy（sf）突变的衰老小鼠会发生自发性乳腺癌和肿瘤肺转移。对Foxp 3sf/+雌性小鼠中循环miR的分析显示，血浆miR-200 c/141和miR-155水平在肿瘤进展和肺转移期间显著增加，并且这些结果在少量乳腺癌患者中得到验证。因此，这些miR似乎是检测人类乳腺癌进展和预测肿瘤对治疗的反应的新型生物标志物的理想候选者。假设和目标：中心假设是循环miR-200 c/141和miR-155是用于早期检测和预测肿瘤进展和治疗反应的有用生物标志物。将在三个特定目的中检验该假设：1）验证大患者群体中的潜在miR生物标志物，2）确定miR生物标志物在肿瘤进展的早期检测和治疗反应的预测中的效用，和3）阐明循环miR生物标志物的发生和调节。方法：首先，Foxp 3sf/+小鼠模型中鉴定的miR生物标志物的上调将使用TaqMan miR测定在大的乳腺癌患者群体中验证。将使用最佳方法、材料、对照和匹配个体，以确保以下指标的统计学显著性： 这个验证。其次，我们将确定miR生物标志物是否可用于早期检测。 肿瘤进展，尤其是肿瘤转移。将通过与当前生物标志物进行比较来评估miR生物标志物在预测乳腺癌患者对治疗的反应中的效用。第三，我们将使用FOXP 3 Tet-off MCF 7细胞来确定miR是否从乳腺癌细胞中释放并受FOXP 3调节。Foxp 3sf/+小鼠模型将用于进一步研究循环miR生物标志物的细胞来源。创新与意义：本研究将首次研究1）miR生物标志物在预测治疗反应中的效用，以及2）体内肿瘤进展期间调节循环miR生物标志物的机制。如果得到证实，这些miR生物标志物将为改善FOXP 3缺陷乳腺癌的预后和降低死亡率提供非侵入性工具。

DESCRIPTION (provided by applicant): Background: MicroRNAs (miRs) are altered in breast tumors, influencing tumor development and progression. As miRs are remarkably stable in circulation, they also have enormous potential as non-invasive biomarkers for breast cancer. Indeed, circulating miRs have been detected in breast cancer patients, but interpretation of their relevance as minimally invasive biomarkers is limited by inconsistent results. Furthermore, the cellular source of circulating miRs and the molecular mechanisms regulating these potential miR biomarkers remain unclear. To address these issues, a highly relevant animal model for in vivo investigation of potential miR biomarkers was established. Aging mice with a Scurfy (sf) mutation of the X-linked tumor suppressor, Foxp3 (Foxp3sf/+), develop spontaneous breast cancer and tumor lung metastases. Analysis of circulating miRs in Foxp3sf/+ female mice revealed that plasma miR-200c/141 and miR-155 levels increase dramatically during tumor progression and lung metastasis, and these results were validated in a small population of breast cancer patients. Thus, these miRs appear as ideal candidates for novel biomarkers to detect the progression of human breast cancer and predict tumor response to therapies. Hypothesis and Goals: The central hypothesis is that circulating miR-200c/141 and miR-155 are useful biomarkers for early detection and prediction of tumor progression and therapeutic response. This hypothesis will be tested in three specific aims: 1) To validate potential miR biomarkers in a large patient population, 2) To determine the utility of the miR biomarkers in the early detection of tumor progression and prediction of therapeutic response, and 3) To elucidate the genesis and regulation of circulating miR biomarkers. Approach: First, the upregulation of the miR biomarkers identified in the Foxp3sf/+ mouse model will be validated in a large population of breast cancer patients using a TaqMan miR assay. The most optimal methods, materials, controls, and matched individuals will be used to ensure the statistical significance of this validation. Second, we will determine if the miR biomarkers are useful for the early detection of tumor progression, especially tumor metastasis. The utility of miR biomarkers in predicting response to treatments in breast cancer patients will be estimated by comparison with current biomarkers. Third, we will use FOXP3 Tet-off MCF7 cells to determine if miRs are released from breast cancer cells and regulated by FOXP3. The Foxp3sf/+ mouse model will be used to further investigate the cellular sources of circulating miR biomarkers. Innovation and Significance: This study will be the first to investigate 1) the utility of the miR biomarkers in predicting response o therapies, and 2) the mechanisms regulating circulating miR biomarkers during tumor progression in vivo. If confirmed, these miR biomarkers will provide non-invasive tools for improving outcomes and decreasing mortality in breast cancers with FOXP3 defects.