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: 8635707
• 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/8635707
• 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; Metric; 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 marker; novel strategies; outcome forecast; oxysterol binding protein; prevent; promoter; prostate cancer cell; public health relevance; pyrosequencing; receptor; receptor binding; response; stem; sulfation; sulfotransferase; synergism; tumor; tumor growth; tumor progression; tumor xenograft

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 specimens 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. .

前列腺癌管理的挑战源于 1) 无法区分惰性前列腺癌和 具有转移潜力的侵袭性恶性肿瘤； 2) 复发性去势抵抗的治疗选择有限 前列腺癌（CRPC）。 CRPC 中雄激素受体 (AR) 重新激活是由于表达升高和 AR 活性，并增加 DHEA 的从头雄激素生物合成。抗 AR/抗雄激素生物合成 药物可以抑制化疗后的癌症几个月，但反应并不普遍。寻找新的预测因子 癌症进展和新药物靶点是高度优先的目标。我们将研究一个新颖的方面 我们的研究揭示了雄激素激活的 AR 信号传导。这需要 i) 雄激素的调节 由前列腺表达的 SULT2B 实现体内平衡，SULT2B 是一种介导胆固醇硫酸化的磺基转移酶 和 DHEA，ii) 增强甲基化 AR 的活性。我们显示 1) SULT2B mRNA 和蛋白质水平是 临床标本中显着减少，组织微阵列的 IHC 染色显示高度统计 癌组织中 SULT2B 显着缺失（p<0.001）； 2) SULT2B沉默导致增殖增加 前列腺癌细胞； 3）维生素D受体（VDR）和氧甾醇诱导型肝X受体（LXR）可以 诱导SULT2B基因（SULT2B1）； 4) AR 在其铰链域的赖氨酸残基处被单甲基化 SET9 赖氨酸甲基转移酶。 SET9 缺失降低了野生型 AR 活性，但不降低甲基化位点突变体 AR 活性； 5）LSD1，一种组蛋白赖氨酸去甲基化酶，可以将甲基化的AR转化为非甲基化的AR； 6) LXR-¿ 是一个潜在的 SET9 和 LSD1 编码基因的调节因子，因为 LXR 响应性顺式元件存在于这两个基因中 基于计算机分析的基因。我们开发了一种可以特异性识别赖氨酸的抗体- 通过蛋白质印迹法甲基化 AR。我们假设晚期前列腺癌与减少 SULT2B 和升高的甲基修饰 AR、LXR-¿ 部分通过防止损失来抑制前列腺癌 SULT2B 和甲基化 AR 的升高以及 VDR 可以协同 LXR 效应。该假设是根据我们的 自己的结果和报告i) LXR- -/- 小鼠在腹​​侧前列腺中表现出更高的雄激素敏感性， 但 AR 水平没有变化； ii) 在前列腺中诱导产生对抗 DHEA 硫酸化的类固醇硫酸酯酶 (Sts) Lxr- -/- 小鼠中的作用，并在 LXR- - 激活的小鼠中受到抑制； iii) LXR 抑制异种移植中的前列腺癌 肿瘤。我们建议确定： 目标 1) SULT2B 缺失在前列腺癌中的重要性以及 DNA 的作用 这种损失中的甲基化。我们将检查 i) 不同样本以了解癌症组织中低 SULT2B 的关联 i) DHT 水平和 AR 靶基因表达，ii) AKR1C3 和 SRD5A1 酶的水平，以及 iii) SULT2B1 基因的甲基化状态。临床变量（包括种族的作用）与 将探讨上述参数。目标 2) LXR 信号传导与 SULT2B 调节的雄激素的动态变化 前列腺稳态、与 VDR 可能的协同作用及其与前列腺癌的相关性。我们将调查 i) SULT2B1 中的 LXR 响应 DNA 顺式元件及其与 LXR-、共调节因子、染色质的相互作用 修饰符； ii) LXR-与VDR在SULT2B诱导和前列腺癌抑制中的协同作用； iii) DHT 水平 LXR- - 体外和体内沉默前列腺癌细胞，以及 Lxr- - 缺失小鼠前列腺，并逆转 骨化三醇对 LXR 沉默的影响； iv) 临床标本中低 SULT2B 与减毒之间的联系 LXR-和LXR-靶向脂肪生成基因的表达。目标 3) 前列腺中 AR 甲基化的意义 癌症及其与 LXR-¿ 的相互作用。我们将检查 i) LXR- 敲低癌症中的甲基化 AR 水平 体外和体内细胞； ii) LXR- 在 SET9 和 LSD1 表达及其与 AR 的关联中的作用 iii) 临床标本甲基化 AR 水平升高（相对于总 AR）。方法：IHC、组织微阵列、 LCM、蛋白质印迹、焦磷酸测序、硫酸氢盐修饰 DNA、启动子测定、ChIP、慢病毒、si RNA、LC- 质谱/质谱。分子生物学家、病理学家和生物统计学家将进行合作。将使用多个核心。 意义：本研究可能揭示预防CRPC的新预测标志物和新干预目标。 。