Prostate Cancer Gene Identification within Candidate Region in African Americans

非裔美国人候选区域内的前列腺癌基因鉴定

• 批准号: 9037625
• 负责人: CATHRYN H BOCK
• 金额: $ 20.47万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2018-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9037625
• 关键词: African American; Agar; American; Biological; Biological Assay; Biological Process; Cancer-Predisposing Gene; Candidate Disease Gene; Cell Count; Cell Line; Cell physiology; Chromosome Mapping; Chromosomes; Chromosomes, Human, Pair 7; Clinical Data; Computer Simulation; DU145; Data; Databases; European; FLNC gene; Freezing; Gene Expression; Genes; Genome; Genotype; Gleason Grade for Prostate Cancer; Health; Immigration; Immunoblot Analysis; Incidence; LNCaP; Literature; Malignant neoplasm of prostate; Maps; Measures; Messenger RNA; Methods; Oncogenes; PC3 cell line; Paraffin Embedding; Population; Predisposition; Prostate; Proteins; Race; Reverse Transcriptase Polymerase Chain Reaction; Risk Factors; Role; Sampling; Tissue Sample; Tissues; United States; Validation; Work; admixture mapping; base; cancer risk; carcinogenesis; cell bank; cell growth; density; disparity reduction; follow-up; genetic risk factor; genome wide association study; insight; interest; mRNA Expression; men; migration; mortality; overexpression; prostate cancer cell line; protein expression; racial difference; racial disparity; screening; tumor

 DESCRIPTION (provided by applicant): There are well documented racial disparities in prostate cancer (PCa) incidence and mortality in the United States between African American (AA) and European American (EA) men. These disparities cannot be fully explained by differences in screening or treatment differences by race, and other environmental and biological risk factors have not been well characterized. We hypothesize that racial differences in the distribution of genetic risk factors may contribute to the observed disparities. We recently identified a region on chromosome 7q31-32 that is statistically significantly associated with prostate cancer in AA men, and there is suggestive evidence for association with PCa aggressiveness as well. The identified region is gene-rich, and thus far we have identified two candidate genes (CPED1 and FLNC) in this region. These are genes that have not been well characterized in the literature, however hints of their role in prostate cancer can be found within previous expression studies. Here, we propose to examine the region on chromosome 7q31-32 in greater depth, using existing samples and data from multiple databases. In Aim 1, we first will examine SNP associations in this region in a much larger independent sample set to confirm our original findings (Aim 1.A). We will then examine available online databases, including dbGAP, GEO, and Oncomine for further evidence of association of genes in this region with PCa risk and aggressiveness (Aim 1.B). Based on the findings of Aims 1.A and B, we will select genes and regions to target with a dense tagSNP panel to better refine our genes of interest in 230 AA PCa cases and 230 AA controls. Aim 2 will explore the functional significance of the top five candidate genes identified in our prior work and in Aim 1, including CPED1 and FLNC, using banked tissue samples (Aim 2.A) and cell lines (Aim 2.B). For Aim 2.A, Expression of mRNA will be assessed in 112 fresh frozen PCa samples selected to represent EA men, AA men, high Gleason grade (GG, >4+3) and low GG (<3+4) equally. Protein expression will be assessed using IHC in paraffin embedded PCa samples, using the same race/grade sampling method. For Aim 2.B, multiple cell lines representing a range of PCa aggressiveness and both EA and AA origin will be used to evaluate protein expression and biological function of these proteins. Protein expression will be determined using immunoblot analysis. If clinical data suggest the candidate gene is overexpressed in PCa, we will knock it down, and if expression is lost in PCa we will overexpress it. We will perform cell growth, transformation, migration and invasion assays to determine if altering gene expression will regulate cellular function. We will also perform cell counting assays to measure cell growth over an eight day period. Soft agar and clonogenic assays will be used to assay transformation. Boyden chamber assays will be used to assess changes in migration and invasion. Study results will provide insight into genetic risk factors for PCa that might help explain racial disparities in incidence and mortality and thereby provide biological targets for reducing these disparities.

 描述(由申请人提供)：在美国，非裔美国人(AA)和欧洲裔美国人(EA)男性之间的前列腺癌(PCA)发病率和死亡率存在明显的种族差异。这些差异不能完全用种族筛查或治疗的差异来解释，其他环境和生物风险因素也没有得到很好的描述。我们假设，遗传风险因素分布上的种族差异可能是造成观察到的差异的原因。我们最近 发现了染色体7q31-32上的一个区域，该区域在统计上与AA男性的前列腺癌相关，而且也有暗示的证据表明与前列腺癌侵袭性相关。该区域富含基因，到目前为止，我们已经在该区域发现了两个候选基因(CPED1和FLNC)。这些基因在文献中还没有得到很好的描述，但可以在 之前的表情研究。在这里，我们建议更深入地研究染色体7q31-32上的区域，使用现有的样本和来自多个数据库的数据。在目标1中，我们将首先在一个更大的独立样本集中检查该地区的SNP相关性，以证实我们最初的发现(目标1.A)。然后，我们将检查可用的在线数据库，包括DBGaP、GEO和Oncomine，以寻找该区域基因与前列腺癌风险和侵袭性关联的进一步证据(目标1.B)。根据AIMS 1.A和B的研究结果，我们将选择基因和区域作为靶点，使用密集的tag SNP面板来更好地提炼230例AA PCa和230例AA对照中我们感兴趣的基因。目标2将利用银行组织样本(目标2.A)和细胞系(目标2.B)，探索我们先前工作和目标1中确定的前五个候选基因的功能意义，包括CPED1和Flc。对于Aim 2.A，将对112例新鲜冷冻的前列腺癌标本进行mRNA表达的评估，这些标本分别代表EA男性、AA男性、高Gleason分级(GG，&gt；4+3)和低GG(&lt；3+4)。在石蜡包埋的PCA样本中，将使用相同的种族/等级抽样方法，使用IHC来评估蛋白质的表达。对于Aim 2.B，将使用代表一系列PCA侵袭性和EA和AA来源的多个细胞系来评估这些蛋白质的蛋白表达和生物学功能。蛋白质的表达将通过免疫印迹分析来确定。如果临床数据显示候选基因在PCa中过度表达，我们将取消它，如果在PCa中丢失表达，我们将过度表达它。我们将进行细胞生长、转化、迁移和侵袭分析，以确定改变基因表达是否会调节细胞功能。我们还将进行细胞计数分析，以测量八天内细胞的生长情况。软琼脂和克隆形成试验将用于检测转化。博伊登小室分析将用于评估迁徙和入侵的变化。研究结果将提供对前列腺癌遗传风险因素的洞察，这可能有助于解释发病率和死亡率的种族差异，从而为减少这些差异提供生物学目标。