Regulation of Intratumor Androgen/Androgen Receptor signaling in Prostrate Cancer

前列腺癌瘤内雄激素/雄激素受体信号传导的调节

• 批准号: 8811322
• 负责人: BANDANA CHATTERJEE
• 金额: --
• 依托单位: SOUTH TEXAS VETERANS HEALTH CARE SYSTEM
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-01 至 2017-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8811322
• 关键词: Accounting; African American; Agonist; Anabolism; Androgen Antagonists; Androgen Receptor; Androgens; Antibodies; Attenuated; Automobile Driving; Beryllium; Biochemical; Biological Assay; Biopsy; Calcitriol; Chemotherapy-Oncologic Procedure; Cholesterol; Chromatin; Clinical; Computer Simulation; CpG Islands; DNA; DNA Methylation; Diagnosis; Drug Targeting; Elements; Enzymes; Epithelial Cell Proliferation; Foundations; Gene Expression; Genes; Genomic DNA; Goals; Growth; Histones; Homeostasis; Hormonal; Human; Hypermethylation; In Vitro; Indium; Indolent; Intervention; Knockout Mice; Laboratories; Lead; Ligand Binding; Link; Liver; Locally Advanced Malignant Neoplasm; Lysine; Malignant Neoplasms; Malignant neoplasm of prostate; Mediating; Medicine; Messenger RNA; Methods; Methylation; Methyltransferase; Modeling; Molecular; Mus; Neoplasm Metastasis; Nuclear Receptors; Pathologist; Pathway interactions; Patients; Pharmaceutical Preparations; Production; Prostate; Prostatic Neoplasms; Proteins; Race; Receptor Signaling; Recurrence; Regulation; Regulator Genes; Relative (related person); Reporting; Risk; Role; SULT2B1; Sampling; Serinus; Signal Pathway; Site; Specimen; Staining method; Stains; Steroids; Sterols; Steryl-sulfatase; Subfamily lentivirinae; TNFRSF10A gene; Tissue Microarray; Tissues; Transactivation; Tumor Tissue; Vitamin D3 Receptor; Western Blotting; base; cancer cell; castration resistant prostate cancer; college; dehydroepiandrosterone; dehydroepiandrosterone sulfotransferase; design; in vivo; knock-down; mutant; novel; novel strategies; outcome forecast; oxysterol binding protein; predictive marker; prevent; promoter; prostate cancer cell; public health relevance; pyrosequencing; receptor; receptor binding; response; stem; sulfation; sulfotransferase; synergism; tumor; tumor growth; tumor progression; tumor xenograft

DESCRIPTION (provided by applicant): Challenges in prostate cancer management stem from 1) inability to distinguish indolent prostate cancer from aggressive malignancy with metastatic potential; 2) limited treatment options for recurrent, castration-resistant prostate cancer (CRPC). Reactivated androgen receptor (AR) in CRPC results from elevated expression and activity of AR, and increased de novo androgen biosynthesis from DHEA. Anti-AR/anti-androgen biosynthesis drugs inhibit post chemotherapy cancer for a few months, but response is not universal. Finding new predictors for cancer progression and new drug targets are high-priority goals. We will examine a novel aspect of androgen-activated AR signaling that was revealed from our study. This entails i) regulation of androgen homeostasis by the prostate-expressed SULT2B, a sulfotransferase which mediates sulfation of cholesterol and DHEA, and ii) enhanced activity of methylated AR. We show 1) SULT2B mRNA and protein levels are markedly reduced in clinical specimens and IHC staining of tissue microarrays revealed highly statistically significant (p<0.001) loss of SULT2B in cancer tissue; 2) SULT2B silencing caused increased proliferation of prostate cancer cells; 3) Vitamin D receptor (VDR) and the oxysterol-inducible liver X receptor (LXR) can induce the SULT2B gene (SULT2B1); 4) AR is monomethylated at a lysine residue in its hinge domain by the SET9 lysine methyltransferase. SET9 depletion reduced wild type but not methylation-site-mutant AR activity; 5) LSD1, a histone lysine demethylase can convert methylated AR to unmethylated AR; 6) LXR-¿ is a potential regulator of genes encoding SET9 and LSD1, since LXR-responsive cis elements are present in these two genes based on in silico analysis. We have developed an antibody that can specifically recognize lysine- methylated AR by western blotting. We hypothesize that advanced prostate cancer associates with reduced SULT2B and elevated methyl-modified AR, LXR-¿ inhibits prostate cancer in part by preventing loss of SULT2B and elevation of methylated AR, and VDR synergizes LXR effects. The hypothesis is built from our own results and from reports that i) LXR- -/- mice show heightened androgen sensitivity in ventral prostates, but no change in AR levels; ii) steroid sulfatase (Sts) which counters DHEA sulfation, was induced in prostates of Lxr- -/- mice and suppressed in LXR- -activated mice; iii) LXR inhibited prostate cancer in xenograft tumors. We propose to determine: Aim 1) significance of SULT2B loss in prostate cancer, and a role for DNA methylation in this loss. We will examine i) diverse specimens for association of low SULT2B in cancer tissue with i) DHT levels and AR target gene expression, ii) levels of the enzymes AKR1C3 & SRD5A1, and iii) methylation status of the SULT2B1 gene. Statistical association of clinical variables (including role of race) with above parameters will be explored. Aim 2) the dynamics of LXR- signaling with SULT2B-regulated androgen homeostasis in prostate, possible synergy with VDR and their relevance in prostate cancer. We will investigate i) LXR-responsive DNA cis element(s) in SULT2B1 and its interaction with LXR- , coregulators, chromatin modifiers; ii) Synergy of LXR- with VDR in SULT2B induction and prostate cancer inhibition; iii) DHT levels in LXR- -silenced prostate cancer cells in vitro & in vivo, and in Lxr- -null mouse prostates and reversal of the effect of LXR silencing by calcitriol; iv) a link in clinical specimes between low SULT2B and attenuated expression of LXR- and LXR- -targeted lipogenic genes. Aim 3) significance of AR methylation in prostate cancer and its interplay with LXR-¿. We will examine i) methylated AR levels in LXR- -knocked down cancer cells in vitro & in vivo; ii) a role for LXR- in SET9 & LSD1 expression and in their association with AR iii) clinical specimens for elevated methylated AR levels (relative to total AR). Methods: IHC, tissue microarray, LCM, western blot, pyrosequencing, bisulfate-modified DNA, promoter assay, ChIP,, lentivirus, si RNAs, LC- MS/MS. Molecular biologists, pathologists and biostatisticians will collaborate. Multiple cores will be used. Significance: This study may reveal new predictive markers and new intervention targets to prevent CRPC.

描述（由申请人提供）： 前列腺癌管理的挑战源于1）无法将顽固的前列腺癌与转移性潜力的侵略性恶性肿瘤区分开； 2）反复持续性，耐castration前列腺癌（CRPC）的有限治疗方案。在CRPC中重新激活的雄激素受体（AR）是由于AR的表达和活性升高，并增加了DHEA的从头雄激素生物合成。抗AR/抗雄激素生物合成药物抑制了几个月的化学疗法癌，但反应并非普遍。寻找有关癌症进展和新药物靶标的新预测因素是高优先级目标。我们将研究从我们的研究中揭示的雄激素激活AR信号的新方面。这需要I）通过前列腺表达的Sult2b调节雄激素稳态，这是一种硫醇和DHEA的硫代转移酶，以及II）增强了甲基化AR活性。我们显示1）SULT2B mRNA和蛋白水平在临床标本中明显降低，而组织微阵列的IHC染色显示出高度统计学意义（P <0.001）在癌症组织中的SULT2B损失； 2）SULT2B沉默导致前列腺癌细胞的增殖增加； 3）维生素D受体（VDR）和氧甲醇诱导的肝X受体（LXR）可以诱导Sult2b基因（SULT2B1）； 4）AR通过SET9赖氨酸甲基转移酶在其铰链结构域的赖氨酸居住区进行单甲基化。 SET9耗竭减少了野生型，但不是甲基化位点突变的AR活性； 5）LSD1，组蛋白赖氨酸脱甲基酶可以将甲基化的AR转换为未甲基化的AR； 6）lxr- - 是编码SET9和LSD1的基因的潜在调节剂，因为这两个基因中存在基于计算机分析中的这两个基因中的LXR反应性顺式元素。我们开发了一种抗体，可以通过蛋白质印迹特异性地识别赖氨酸甲基化的AR。我们假设先进的前列腺癌与SULT2B降低和甲基改性AR的升高相关性，LXR-€部分通过防止SULT2B的损失和甲基化AR的升高来抑制前列腺癌，VDR协同使LXR效应协同。该假设是根据我们自己的结果建立的，并从报告中构建了i）lxr- - / - 小鼠显示出腹前列腺中雄激素敏感性的提高，但AR水平没有变化； ii）在LXR--/ - 小鼠的前列腺中诱导了反硫酸硫酸化的类固醇硫酸酶（STS），并在LXR-激活的小鼠中抑制； iii）LXR抑制了特征肿瘤中的前列腺癌。我们建议确定：目标1）SULT2B在前列腺癌中丧失的意义，以及DNA甲基化在这种损失中的作用。我们将检查i）癌组织中低sult2b与i）DHT水平和AR靶基因表达的潜水标本，ii）SULT2B1基因的酶AKR1C3＆SRD5A1的水平AKR1C3＆SRD5A1和III）甲基化状态。将探索临床变量（包括种族的作用）与上述参数的统计关联。目标2）在前列腺中通过SULT2B调节的雄激素稳态的LXR信号动力学，可能与VDR的协同作用及其在前列腺癌中的相关性。我们将研究i）sult2b1中的LXR响应DNA顺式元素及其与LXR-，核心节，染色质修饰剂的相互作用； ii）LXR-与SULT2B诱导和前列腺癌抑制的VDR协同； iii）在体外和体内LXR-溶解的前列腺癌细胞中的DHT水平，在lxr- null小鼠前列腺中的lxr- null小鼠前列腺中的LXR沉默效应和骨化的影响； iv）低sult2b和LXR-靶向脂肪生成基因的临床状态的联系。 AIM 3）AR甲基化在前列腺癌及其与LXR-的相互作用中的重要性。我们将检查I）在体外和体内cance骨细胞下lxr-敲低的甲基化AR水平； ii）LXR-在SET9＆LSD1表达中的作用，以及与AR III的相关性，用于甲基化AR水平升高（相对于总AR）。方法：IHC，组织微阵列，LCM，Western blot，pyrosequencing，Bisulfate-Motified DNA，启动子测定，芯片，慢病毒，Si rnas，LC-MS/MS。分子生物学家，病理学家和生物统计学家将合作。将使用多个核心。意义：这项研究可能揭示了新的预测标志物和新的干预目标，以防止CRPC。