Epigenetic changes in a PhIP-induced prostate cancer model in hCYP1A mice

hCYP1A 小鼠 PhIP 诱导的前列腺癌模型的表观遗传变化

• 批准号: 8911268
• 负责人: Jayson Xiao-Chen Chen
• 金额: $ 2.71万
• 依托单位: RUTGERS, THE STATE UNIV OF N.J.
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8911268
• 关键词: 2-Amino-1-Methyl-6-Phenylimidazo[4,5-b]pyridine; ABCB1 gene; Aberrant DNA Methylation; Age; Atrophic; CDKN2A gene; Cancer Etiology; Carcinogens; Carcinoma; Cessation of life; Cytochrome P-450 CYP1A2; DNA; DNA Adduction; DNA Methylation; DNA Modification Methylases; DNA Sequence Alteration; Data; Developed Countries; Development; Diagnosis; Diet; Disease; Dissection; E-Cadherin; Enzymes; Epigenetic Process; Epithelial; Event; Exposure to; Fishes; Future; GSTP1 gene; Gene Expression Regulation; Genes; Genomics; Hematoxylin and Eosin Staining Method; Heterocyclic Amines; High temperature of physical object; Human; Hypermethylation; Inflammation; Laboratories; Lasers; Lateral; Lead; Literature; MAP Kinase Gene; MGMT gene; Maintenance; Malignant Neoplasms; Malignant neoplasm of prostate; Manuscripts; Meat; Mediating; Methods; Methylation; Methyltransferase; Modeling; Molecular; Mus; Mutation; Normal Cell; Nucleotides; Oncogenic; Oxidative Stress; Pathogenesis; Pathway interactions; Play; Prostate; Prostatic Intraepithelial Neoplasias; Public Health; Race; Rattus; Research; Reverse Transcriptase Polymerase Chain Reaction; Risk Factors; Role; Signal Pathway; Signal Transduction; Staging; Techniques; Testing; Time; Transcription Factor AP-1; Tumor Suppressor Genes; United States; Up-Regulation; Western Blotting; base; cancer risk; carcinogenesis; cooking; histone modification; in vivo; inhibitor/antagonist; insight; men; novel; promoter; prostate cancer model; prostate cancer prevention; prostate carcinogenesis; research study

DESCRIPTION (provided by applicant): Prostate cancer is one of the most frequently diagnosed malignancies in developed countries and a leading cause of cancer-related death among men in the United States. Prostate cancer involves numerous risk factors, particularly age, race, and diet. Exposure to PhIP, a dietary carcinogen generated from high temperature cooking of meat and fish, has been associated with prostate cancer risk. In this study, we will investigate carcinogenesis of a PhIP-induced prostate cancer model in CYP1A-humanized (hCYP1A). The objectives are to determine the induction mechanism of DNMT1, a major methyltransferase enzyme involved in DNA methylation, and identify the promoter DNA hypermethylation of genes caused by the upregulated level of DNMT1. Based on previous studies and preliminary data, the hypotheses are that DNMT1 is induced by the Ras/MAPK/AP-1 and/or PI3K/Akt signaling pathway and that the upregulation of DNMT1 causes hypermethylation and inactivation of key regulatory and tumor suppressor genes in the prostate of the humanized mice. To test these hypotheses, three specific aims are proposed: (1) elucidate the mechanism of DNMT1 induction in hCYP1A mice at 1, 3, 7, and 14 days after PhIP treatment; (2) identify promoter DNA hypermethylation of key regulatory and tumor suppressor genes caused the elevated level of DNMT1 using methylation PCR array; and (3) investigate the relationship between DNMT1 upregulation in the early time- points (1 & 3 days) and the late stages (30 & 40 weeks) of PhIP-induced carcinogenesis. The proposed experiments will employ standard histological (H&E), immunohistochemical (IHC), and molecular techniques (Western Blotting & quantitative RT-PCR) as well as more specialized methods (Laser Capture Micro- dissection, Methylation Specific PCR, & DNA methylation PCR array). The study will reveal the induction mechanism of DNMT1 and the epigenetic changes caused by the PhIP carcinogen. Determining the molecular mechanism and alterations in the PhIP-treated hCYP1A mice will enhance our understanding of prostate carcinogenesis and cancer development.

描述（由申请人提供）：前列腺癌是发达国家最常诊断出的恶性肿瘤之一，也是美国男性癌症相关死亡的主要原因。前列腺癌涉及许多危险因素，特别是年龄、种族和饮食。 PhIP 是一种由高温烹饪肉和鱼产生的膳食致癌物，接触它与前列腺癌风险相关。在这项研究中，我们将研究 CYP1A 人源化 (hCYP1A) 中 PhIP 诱导的前列腺癌模型的致癌作用。目的是确定 DNMT1（一种参与 DNA 甲基化的主要甲基转移酶）的诱导机制，并鉴定由 DNMT1 水平上调引起的基因启动子 DNA 高甲基化。基于之前的研究和初步数据，假设DNMT1是由Ras/MAPK/AP-1和/或PI3K/Akt信号通路诱导的，并且DNMT1的上调导致人源化小鼠前列腺中关键调节和肿瘤抑制基因的高甲基化和失活。为了检验这些假设，提出了三个具体目标：（1）阐明 PhIP 治疗后 1、3、7 和 14 天 hCYP1A 小鼠中 DNMT1 诱导的机制； (2) 利用甲基化PCR阵列鉴定导致DNMT1水平升高的关键调控基因和抑癌基因的启动子DNA高甲基化； (3)研究PhIP诱导的癌变早期时间点（1和3天）和晚期（30和40周）DNMT1上调之间的关系。拟议的实验将采用标准组织学 (H&E)、免疫组织化学 (IHC) 和分子技术（蛋白质印迹和定量 RT-PCR）以及更专业的方法（激光捕获显微解剖、甲基化特异性 PCR 和 DNA 甲基化 PCR 阵列）。该研究将揭示DNMT1的诱导机制以及PhIP致癌物引起的表观遗传变化。确定 PhIP 处理的 hCYP1A 小鼠的分子机制和变化将增强我们对前列腺癌发生和癌症发展的理解。