Identification of Biomarkers for Testicular Cancer

在过去的40年里，睾丸生殖细胞肿瘤(TGCT)的发病率翻了一番。年增长率为 据报道，36%的人是高加索人。睾丸癌是影响男性的最常见的恶性肿瘤 年龄在14-40岁，占在这个年龄段诊断的所有恶性肿瘤的60%。尽管治愈率很高， 它们是这一年龄段最常见的实体肿瘤致死原因。除癌基因外 肿瘤抑制基因(TSG)的激活、失活在肿瘤发生发展中起重要作用 肿瘤发生学。根据修订后的克努森两次命中假说，肿瘤抑制因子的完全失活 基因(TSG)通常涉及两个遗传或表观遗传事件：1)大片段的丢失或重组 染色体DNA区域包含一个亲本等位基因和一个局部突变事件，使 第二等位基因2)一个等位基因的定位突变和另一个等位基因的甲基化3)一个等位基因的杂合性缺失和 另一个等位基因甲基化4)双等位基因甲基化。我们最近发现了几种特定于癌症的 一种将概率搜索算法与药理学相结合的稳健方法使基因甲基化 肿瘤特异性甲基化基因无偏见和精确全球定位的揭示策略。我们也 验证了对50多个基因的高通量分析(QMSP，定量甲基化特异性PCR) 对几种类型的癌症进行稳健的分析，具有很高的敏感性和特异性。同时，我们也开创了 使用单核苷酸多态(SNP)阵列分析癌症杂合性丢失(LOH)和 使用基于SNP的阵列对尿中膀胱癌的诊断进行了一项主要研究的证明 沉淀物。我们现在提出以下目标：1.分析睾丸染色体丢失的模式 应用单核苷酸多态(SNP)阵列杂交技术检测10,000例以上不同分期的肿瘤 标记2.以一种稳健的方法发现睾丸癌特异性甲基化基因 在整个人类基因组中的概率搜索算法和已建立的药物揭开 癌症细胞系的策略。3.比较不同发育阶段的基因组和表观基因组图谱 睾丸癌 在实现了我们的前两个特定目标之后，我们将确定一个或多个基因在基因和基因的关键区域 表观遗传学改变与睾丸癌有关。此外，对这些区域进行了识别，并对 基因和表观遗传学的改变将为睾丸癌进展的生物学提供重要的线索。 功能研究可能为生殖细胞永生化的最初步骤和后续步骤提供深入的见解 癌症的进展。最终，SNP标记和甲基化标记可能导致新的诊断， 睾丸癌的监测和治疗方法。此外，这一全面的分析将引导我们 了解睾丸癌发生的生物学基础。

The incidence of testicular germ cell tumors (TGCT) has doubled in the past 40 years. An annual increase of 36% is reported for Caucasian populations.Testicular cancer is the most common malignancy affecting males aged 14-40 and accounting for up to 60% of all malignancies diagnosed at this age. Despite a high cure rate, they represent the most frequent cause of death from solid tumors in this age group. In addition to oncogene activation, the inactivation of tumor suppressor genes (TSGs) has been shown to play an important role in tumorigenesis. According to the revised Knudson's two-hit hypothesis, full inactivation of a tumor suppressor gene (TSGs) often involves two genetic or epigenetic events: 1) the loss or recombination of large chromosomal DNA regions containing one parental allele and a localized mutational event inactivating the second allele 2) localized mutation in one allele and methylation in another allele 3) LOH in one allele and methylation in another allele 4) biallelic methylation. We have recently discovered several cancer specific methylated genes by a robust approach that couples probabilistic search algorithms with the pharmacologic unmasking strategy for unbiased and precise global localization of tumor-specific methylated genes. We also validated a highthroughput assay for more than 50 genes (QMSP, quantitative methylation specific PCR) for robust analysis of several types of cancer with high sensitivity and specificity. In parallel, we have pioneered the use of single nucleotide polymorphism (SNP) arrays for analyzing cancer loss-of-heterozygosity (LOH) and performed a proof of principal study using SNP based arrays for the diagnosis of bladder cancer in urine sediment. We now propose the following aims: 1. To analyze patterns of chromosomal loss in testicular cancers from different stages using single nucleotide polymorphism (SNP) array hybridization of over 10,000 markers 2. To discovery of testicular cancer specific methylated genes by a robust approach that couples probabilistic search algorithms in the entire human genome with an established pharmacologic unmasking strategy in cancer cell lines. 3. To compare the genomic and epigenomic patterns in different stages of testicular cancer After carrying our first 2 specific aims, we will identify the gene or genes in a critical area of genetic and epigenetic alterations involved in testicular cancer. In addition, identification of these area and comparison of genetic and epigenetic alterations will shed important light on the biology of testicular cancer progression. Functional studies may provide insights into the first steps of germ cell immortilization and subsequent progression in cancer. Ultimately, SNP markers and methylation markers may lead to new diagnostic, monitoring and therapeutic approaches in testicular cancer. In addition this comprehensive analysis will lead us to understand the biology of testicular cancer development.