CYP1A1 and CYP1B1 genes in race-related Prostate Cancer

描述（由申请人提供）：本项目的主要目的是研究细胞色素P450 1A 1（CYP 1A 1）和细胞色素P4501 B1（CYP 1B 1）基因的过度表达是否是种族相关前列腺癌的风险因素。理由是非洲裔美国人患晚期前列腺癌的风险是白人的两倍。40-60岁的非洲裔美国男性因前列腺癌的死亡率几乎是同龄白色男性的2-3倍。前列腺癌发病率的种族/民族差异的遗传基础尚不清楚。为了解决这一问题，我们针对CYP 1A 1和CYP 1 B1基因，因为它们的产物（2-OH-E2和4-OH-E2）具有高度致癌性。这是研究前列腺癌发病率种族/民族差异的遗传基础的第一步。根据我们先前的出版物和初步数据，我们假设CYP 1A 1和CYP 1B 1基因是种族相关前列腺癌的危险因素。具体目标1：验证CYP 1A 1和CYP 1B 1基因在种族相关性前列腺癌恶变过程中过度激活的假设。在这个特定的目标下，我们将通过实时PCR分析不同阶段和不同等级的种族相关前列腺癌中CYP 1A 1和CYP 1 B1基因的mRNA表达。原位杂交将用于定位前列腺组织中的基因表达。将通过放射性同位素方法分析前列腺组织中CYP 1 A1和CYP 1 B1的酶活性。具体目标#2：检验CYP 1A 1和CYP 1B 1基因单核苷酸多态性是前列腺癌危险因素的假设。在此特定目标下，我们将分析CYPIA 1基因的4个多态性位点和CYP 1 B1基因的6个多态性位点在不同阶段和不同级别的种族相关前列腺癌中的单核苷酸多态性。将通过PCR-RFLP（限制性片段长度多态性）和直接基因组测序分析SNP。具体目标3：采用定点诱变试验，验证在大肠杆菌中转染CYP 1A 1和CYP 1 B1多态性变体可超活化雌激素羟化酶活性的假设。我们将研究CYP 1 A1和CYP 1 B1的多态性变体与野生型相比是否具有更高的雌激素羟化酶活性。我们还将研究雌激素羟化酶活性和雌激素代谢产物（2-OHE 2和4-OH-E2）是否与前列腺癌复发相关。

DESCRIPTION (provided by applicant): The main goal of this project is to investigate whether over-expression of cytochrome P450 1A1 (CYP1A1) and cytochrome P4501 B1 (CYP1B1) genes can be risk factors for race-related prostate cancer. Rationale is that African-Americans have twice the risk of Whites for presenting with advanced-stage prostate cancer. The mortality of African-American men 40-60 years of age due to prostate cancer is almost 2-3 folds greater than that of White men of the same age. The genetic basis for racial / ethnic differences in prostate cancer incidence is not known. To address this problem, we have targeted the CYP1A1 and CYP1 B1 genes because their products (2-OH-E2 and 4-OH-E2) are highly carcinogenic. This is a first step towards investigating the genetic basis for racial / ethnic differences in prostate cancer incidence. Based on our prior publications and preliminary data, we hypothesize that the CYP1A1 and CYP1 B1 genes are risk factors for race-related prostate cancer. Specific Aim # 1: To test the hypothesis that CYP1A1 and CYP1 B1 genes are hyper-activated during malignant transformation of race-related prostate cancer. Under this specific aim, we will analyze mRNA expression of the CYP1A1 and CYP1 B1 genes by real-time PCR in different stages and grades of race-related prostate cancer. In situ hybridization will be used to localize gene expression in prostate tissues. Enzyme activities of CYP1 A1 and CYP1 B1 will be analyzed in prostate tissues by radio-isotopic methods. Specific Aim # 2: To test the hypothesis that single nucleotide polymorphisms of CYP1A1 and CYP1 B1 genes are risk factors for prostate cancer. Under this specific aim, we will analyze single nucleotide polymorphisms of four polymorphic sites of the CYPIA1 gene and six polymorphic sites of the CYP1 B1 gene in different stages and grades of race-related prostate cancer. SNPs will be analyzed by PCR-RFLP (restriction fragment length polymorphism) and direct genomic sequencing. Specific Aim # 3: To test the hypothesis that transfection of polymorphic variants of CYP1A1 and CYP1 B1 in E.Coli can hyperactivate estrogen hydoxylase activities using site-directed mutagenesis assays. We will investigate whether polymorphic variants of CYP1 A1 and CYP1 B1 have higher estrogen hydroxylase activities as compared to wild-type. We will also investigate whether estrogen hydroxylase activities and estrogen metabolites (2-OHE2 and 4-OH-E2) are associated with prostate cancer recurrence.