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. .

前列腺癌治疗的挑战源于1)无法区分惰性前列腺癌和前列腺癌 有转移潜能的侵袭性恶性肿瘤；2)复发、耐阉割的治疗选择有限 前列腺癌(CRPC)。CRPC中雄激素受体(AR)的重新激活是由于表达和 AR活性，并增加DHEA的从头合成雄激素。抗AR/抗雄激素生物合成 药物可以在几个月内抑制化疗后的癌症，但反应并不普遍。寻找新的预测者 对于癌症进展和新药靶点是高度优先的目标。我们将从一个新的方面考察 我们的研究揭示了雄激素激活的AR信号。这需要：1)调节雄激素 前列腺表达的SULT2B的动态平衡，SULT2B是一种介导胆固醇硫酸盐化的磺基转移酶 和脱氢表雄酮(DHEA)，以及II)甲基化AR活性增强。我们发现1)SULT2B的mRNA和蛋白水平是 临床标本显著减少，组织芯片免疫组化染色显示高度统计学意义 癌组织中SULT2B的显著丢失(p&lt；0.001)；2)SULT2B沉默导致肿瘤细胞增殖增加 3)维生素D受体(VDR)和氧化甾醇诱导的肝X受体(LXR)可以 诱导SULT2B基因(SULT2B1)；4)AR在其铰链结构域的赖氨酸残基上单甲基化 SET9赖氨酸甲基转移酶。SET9缺失会降低野生型的AR活性，但不会降低甲基化突变的AR活性； 5)LSD1，一个组蛋白赖氨酸去甲基酶，可以将甲基化的AR转化为未甲基化的AR；6)LXR-？是一个潜在的 编码SET9和LSD1的基因的调节，因为这两个基因中存在LXR反应的顺式元件 基于电子计算机分析的基因。我们已经开发出一种抗体，可以特异性识别赖氨酸- 蛋白质印迹法检测AR甲基化。我们假设晚期前列腺癌与 SULT2B和甲基化修饰的AR，LXR-β抑制前列腺癌的部分机制是通过阻止 SULT2B和甲基化AR的升高以及VDR协同LXR效应。这一假说是从我们的 自己的结果和报告：i)LXR--/-小鼠显示出腹侧前列腺对雄激素的敏感性增强， 但AR水平没有变化；ii)在前列腺中诱导了对抗DHEA硫化的类固醇硫酸酯酶(Sts) 对LXR--/-小鼠的抑制作用；III)LXR对异种移植前列腺癌的抑制作用 肿瘤。我们建议确定：目的1)SULT2B缺失在前列腺癌中的意义，以及DNA的作用 甲基化在这种缺失中的作用。我们将检查i)癌症组织中低SULT2B相关的不同样本 与i)DHT水平和AR靶基因表达，ii)AKR1C3和SRD5A1酶水平，以及iii) SULT2B1基因甲基化状态。临床变量(包括种族的作用)与 我们将探讨上述参数。目的2)SULT2B调节的雄激素对LXR信号的影响 前列腺癌中的动态平衡，与VDR的可能协同作用及其相关性。我们会调查的 1)SULT2B1的LXR顺式元件(S)及其与LXR-、共调节因子、染色质的相互作用 改良剂；ii)LXR-与VDR在SULT2B诱导和前列腺癌抑制中的协同作用；iii)DHT水平在 LXR-沉默的前列腺癌细胞在体内外和在LXR-空的小鼠前列腺和逆转 骨化三醇抑制LXR的作用；IV)临床标本中低SULT2B与减弱之间的联系 LXR-和LXR-靶向致脂基因的表达。目的3)AR甲基化在前列腺癌中的意义 癌症及其与LXR的相互作用。我们将检查LXR中甲基化AR的水平--被击倒的癌症 体外和体内细胞；II)LXR-在SET9和LSD1表达中的作用及其与AR III的关系) 甲基化AR水平升高的临床标本(相对于总AR)。方法：免疫组织化学、组织芯片、 LCM，蛋白质印迹，焦糖测序，硫酸盐修饰的DNA，启动子分析，芯片，慢病毒，单链RNA，LC- 分子生物学家、病理学家和生物统计学家将进行合作。将使用多核。 意义：这项研究可能揭示新的预测标记物和新的干预靶点来预防CRPC。 。