Evaluation of TP53 mutations in non-cancerous tissue as novel biomarkers of ovarian cancer risk.

评估非癌组织中的 TP53 突变作为卵巢癌风险的新型生物标志物。

• 批准号: 9807872
• 负责人: Rosa Ana Risques
• 金额: $ 16.91万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-06-03 至 2021-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9807872
• 关键词: Age; Area; BRCA1 Mutation; BRCA1 gene; BRCA2 Mutation; BRCA2 gene; Biological Markers; Biopsy; Blood; Clinical; Clustered Regularly Interspaced Short Palindromic Repeats; Constitutional; Coupled; DNA; Data; Databases; Development; Diagnosis; Disease; Evaluation; Excision; Frequencies; Future; Genes; Genetic Predisposition to Disease; Genome; Germ-Line Mutation; Goals; Gynecologic Oncology; Gynecologic Surgical Procedures; High-Risk Cancer; Human; Individual; Inherited; Investigation; Lead; Life; Malignant - descriptor; Malignant Neoplasms; Malignant neoplasm of ovary; Mammalian Oviducts; Measurement; Measures; Methods; Mutate; Mutation; Mutation Detection; Normal tissue morphology; Operative Surgical Procedures; Ovarian Serous Adenocarcinoma; Ovary; Pap smear; Pathogenicity; Performance; Predictive Value; Predisposition; Prevention; Problem Solving; Process; Research; Risk; Risk Assessment; Sampling; Serous; Site; Somatic Mutation; TP53 gene; Testing; Time; Tissue Banks; Tissues; Universities; University resources; Washington; Woman; actionable mutation; base; cancer biomarkers; cancer risk; cancer type; cost; deep sequencing; high risk; improved; mortality; mutant; mutational status; novel marker; potential biomarker; preservation; prevent; prophylactic; repository; tool; tumor; tumor progression

Evaluation of TP53 mutations in non-cancerous tissue as novel biomarkers of ovarian cancer risk TP53 is the most mutated gene in human tumors. Surprisingly, recent research has revealed that TP53 mutations are also found at very low frequency in non-cancerous tissues. Whether these mutations increase the risk of future cancer progression is currently unknown. However this possibility is supported by the fact that TP53 mutations in normal tissue are similar to TP53 mutations in cancers: they tend to cluster in hotspots and are mostly deleterious. This indicates an ongoing evolutionary process of positive selection that takes place through life and might result in cancer progression in some individuals. Accordingly, we hypothesize that individuals with an elevated load of somatic TP53 mutations might be at a higher risk of developing cancer. We will test this hypothesis for high grade serous ovarian cancer (HGSOC), a cancer type driven by TP53 mutations and which is typically diagnosed at late stage, causing high mortality. The need for better HGSOC risk biomarkers is especially critical for women with germline mutations in BRCA1 and BRCA2 (BRCA1/2 carriers) who have about 45% and 20% lifelong risk of HGSOC, respectively. Using an ultra-accurate sequencing method called Duplex Sequencing we recently demonstrated that women with HGSOC as well as BRCA1/2 carriers harbor higher frequency of TP53 mutations in blood DNA. Similarly, Pap smear DNA from women with HGSOC contained significantly higher frequency of TP53 cancer-like mutations than Pap smears from women without cancer. These findings support our hypothesis that a constitutionally higher load of TP53 mutant clones might elevate the risk of HGSOC. We propose to further explore these results and their potential utility as cancer biomarkers taking advantage of (1) CRISPR-DS, a Duplex Sequencing based method developed by our group that is more efficient, faster, cheaper, and requires less DNA than the original method; and (2) the University of Washington Gynecologic Oncology Tissue Bank, which has an extensive repository of blood and Pap smear samples collected from women that underwent gynecological surgery for suspected masses or prophylactically due to inherited cancer susceptibility. In Aim 1, we will perform ultra-deep (~3,000x) CRISPR-DS TP53 sequencing of blood DNA from BRCA1/2 carriers and non-carriers with and without HGSOC and we will determine associations between TP53 mutations, HGSOC, and germline BRCA1/2 mutations. For a subset of women, in Aim 2 we will test whether TP53 mutations in Pap smear DNA are also associated with HGSOC and/or germline mutation status and whether the combination of TP53 mutational information from Pap smear and blood has a better cancer predictive value than either test separately. This research breaks ground on the potential biomarker value of somatic TP53 mutations, which were unrecognized until recently due to their very low frequency. CRISPR-DS allows their accurate measurement in a high-throughput manner, thus enabling the development of a translational biomarker that could lead to improved prediction and prevention of HGSOC as well as other cancers driven by TP53 mutations.

非癌组织中TP 53突变作为卵巢癌风险新生物标志物的评估 TP 53是人类肿瘤中突变最多的基因。令人惊讶的是，最近的研究表明，TP 53 在非癌性组织中也发现了非常低频率的突变。这些突变是否会增加 未来癌症进展的风险目前尚不清楚。然而，这种可能性得到以下事实的支持： 正常组织中的TP 53突变与癌症中的TP 53突变相似：它们倾向于聚集在热点中， 大多是有害的。这表明一个正在进行的积极选择的进化过程， 并可能导致某些个体的癌症进展。因此，我们假设， 具有升高的体细胞TP 53突变负荷的个体可能处于更高的发展癌症的风险中。我们 我将检验这一假说的高级别浆液性卵巢癌（HGSOC），一种癌症类型驱动的TP 53 突变，并且通常在晚期诊断，导致高死亡率。需要更好的HGSOC 风险生物标志物对于BRCA 1和BRCA 2（BRCA 1/2）生殖系突变的女性尤其重要 携带者）分别有约45%和20%的HGSOC终身风险。使用一个超精确的 我们最近用一种称为双链体测序的测序方法证明， BRCA 1/2携带者血液DNA中TP 53突变频率较高。同样地，巴氏涂片DNA 患有HGSOC的妇女的TP 53癌样突变频率显著高于巴氏涂片 没有癌症的女性。这些发现支持了我们的假设，即TP 53的组成性高负荷 突变克隆可能增加HGSOC的风险。我们建议进一步探索这些结果及其潜力 作为癌症生物标志物的实用性，利用（1）CRISPR-DS，基于双链体测序的方法 由我们的团队开发，比原来的方法更有效，更快，更便宜，需要更少的DNA; 和（2）华盛顿大学妇科肿瘤组织库，其具有广泛的 血液和巴氏涂片样本收集自接受妇科手术的妇女， 肿块或由于遗传性癌症易感性而引起的炎症。在目标1中，我们将执行超深（~3，000倍） BRCA 1/2携带者和非携带者（含和不含HGSOC）血液DNA的CRISPR-DS TP 53测序 我们将确定TP 53突变、HGSOC和生殖系BRCA 1/2突变之间的关联。为 在目标2中，我们将测试巴氏涂片DNA中的TP 53突变是否也与 HGSOC和/或生殖系突变状态以及来自HGSOC和/或生殖系突变状态的TP 53突变信息的组合是否与HGSOC和/或生殖系突变状态相关。 巴氏涂片和血液检查比单独进行任何一种检查都有更好的癌症预测价值。这项研究打破了 基于体细胞TP 53突变的潜在生物标志物价值，直到最近才被认识到 因为它们的频率很低。CRISPR-DS允许以高通量方式进行精确测量， 从而能够开发可导致改进的预测的翻译生物标志物， 预防HGSOC以及由TP 53突变驱动的其他癌症。