E2F family transcription factors are directly regulated by TRIM28 to promote castration-resistance in prostate cancer

E2F家族转录因子受TRIM28直接调节促进前列腺癌去势抵抗

基本信息

批准号：
10290070
负责人：
Ka wing Fong
金额：
$ 7.65万
依托单位：
UNIVERSITY OF KENTUCKY
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-07-05 至 2023-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10290070
关键词：
American Androgen Antagonists Androgen Receptor Androgens Antibodies Binding Biological Assay CRISPR/Cas technology Cancer Cell Growth Cancer Etiology Cancer Patient Castration Cell Cycle Cell Cycle Progression Cell Extracts Cell Line Cell Proliferation Cells Cessation of life ChIP-seq Clinical Clustered Regularly Interspaced Short Palindromic Repeats DNA Binding DNA biosynthesis E2F transcription factors Family Gene Expression Generations Genetic Transcription Genomic approach Genomics Growth Harvest Human Immunohistochemistry LNCaP Luciferases Malignant Neoplasms Malignant neoplasm of prostate Mediating Metastatic Prostate Cancer Oncogenic Pathway interactions Patients Play Promoter Regions Proteins RNA Receptor Signaling Regulation Reporter Reporting Resistance Role Running Signal Transduction Specimen Testing Tissue Microarray Transactivation Transcriptional Activation Ubiquitination Western Blotting Xenograft procedure advanced prostate cancer androgen deprivation therapy androgen sensitive biobank castration resistant prostate cancer cell growth cofactor cohort efficacy evaluation experimental study genetic signature genome-wide inhibitor/antagonist knock-down men mutant prevent promoter prostate cancer cell prostate cancer cell line prostate cancer progression small hairpin RNA small molecule inhibitor targeted treatment therapeutic target transcription factor transcriptome tumor growth tumor xenograft tumorigenic

项目摘要

Prostate cancer (PCa) is the second-leading cause of cancer-related death in American men. Androgen deprivation therapies that target the androgen receptor (AR) are the mainstay treatment for metastatic PCa. New generation anti-androgen enzalutamide (Enz) significantly increases PCa patient survival. However resistance to Enz develops rapidly. Importantly, castration- resistant prostate cancer (CRPC) is driven primarily by aberrant activation of the AR in the milieu of low androgen. The AR exerts its tumorigenic roles mainly through genomic regulation of target gene expression. This genomic action is tightly regulated by a number of cofactors, and one of which is TRIM24. We recently reported that TRIM28 is an upstream regulator of TRIM24 protein stability in CRPC, where both TRIM24 and TRIM28 expression is highly elevated. Mechanistically, TRIM28 stabilizes TRIM24 by preventing TRIM24 from SPOP-driven ubiquitination and degradation, and thereby TRIM24 is able to reactivate AR signaling in CRPC. To explore the TRIM28-mediated downstream signaling, genome-wide transcriptome analysis revealed that TRIM28 engaged in various oncogenic pathway including cell cycle and DNA replication. By interrogating cell cycle signature genes, we showed that TRIM28 induces E2F1, E2F2 and E2F3 gene expression in PCa. In addition, TRIM28 ChIP-seq revealed that TRIM28 directly binds to promoter region of transcription factor E2F1-E2F3, which play a pivotal role in activating transcription of the genes required for cell cycle progression. Further, deregulated expression or activity of the E2F family has often been detected in many human cancers, which leads to uncontrolled cell proliferation. In this proposal, we hypothesize that E2F transcription factor is a critical downstream target of TRIM28 and clinically-available E2F small molecules inhibitor LY101-4B may suppress CRPC progression. To test this hypothesis, three specific aims are proposed. In Aim1 we will first validate the direct regulation of E2F1-E2F3 gene expression by TRIM28 with the use of genomic approaches. Aim2 will examine clinical expression of E2F and evaluate the efficacy of E2F inhibitor in CRPC cell lines and xenografts.

前列腺癌（PCA）是美国男性与癌症相关死亡的第二大原因。靶向雄激素受体（AR）的雄激素剥夺疗法是主要治疗用于转移PCA。新一代抗雄激素恩扎拉胺（ENZ）显着增加 PCA患者生存。但是对ENZ的抵抗力迅速发展。重要的是，cast割 - 耐药性前列腺癌（CRPC）主要由MIRIEU中AR异常激活驱动低雄激素。 AR主要通过靶标基因组调节发挥其致瘤作用基因表达。这种基因组作用受许多辅助因子的严格调节，其中一种这是Trim24。我们最近报道说TRIM28是TRIM24蛋白的上游调节剂 CRPC中的稳定性，其中TRIM24和TRIM28表达均高度升高。机械上， TRIM28通过防止Trim24稳定TRIM24，以免散布驱动的泛素化和降解，因此TRIM24能够在CRPC中重新激活AR信号。探索 TRIM28介导的下游信号传导，全基因组转录组分析表明， TRIM28参与了各种致癌途径，包括细胞周期和DNA复制。经过询问细胞周期签名基因，我们表明TRIM28诱导E2F1，E2F2和E2F3 PCA中的基因表达。此外，TRIM28芯片seq表明TRIM28直接结合到转录因子E2F1-E2F3的启动子区域，在激活中起关键作用细胞周期进程所需的基因的转录。此外，放松调节表达或在许多人类癌症中经常发现E2F家族的活动，这导致不受控制的细胞增殖。在此提案中，我们假设E2F转录因子是一个 TRIM28和临床上可用的E2F小分子抑制剂的关键下游靶标 LY101-4B可以抑制CRPC的进展。为了检验这一假设，三个具体目标是建议的。在AIM1中，我们将首先验证E2F1-E2F3基因表达的直接调节 TRIM28使用基因组方法。 AIM2将检查E2F和E2F的临床表达评估E2F抑制剂在CRPC细胞系和异种移植物中的功效。