Proliferating cell nuclear antigen in regulation of androgen receptor signalings in castration-resistant prostate cancer cells

增殖细胞核抗原对去势抵抗性前列腺癌细胞雄激素受体信号传导的调节

基本信息

批准号：
10544062
负责人：
Zhongyun Dong
金额：
$ 18.56万
依托单位：
UNIVERSITY OF CINCINNATI
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-01-01 至 2024-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10544062
关键词：
Androgen Receptor Androgen Response Element Apoptosis Attenuated Automobile Driving Binding Binding Proteins Biological Assay C-terminal Cell Cycle Progression Cell Survival Cell membrane Cells Chromatin Complex Consensus Sequence DNA Damage DNA Repair DNA biosynthesis Data Development Disease-Free Survival FDA approved Genes Genetic Transcription Gleason Grade for Prostate Cancer Growth Innovative Therapy Interruption LNCaP Legal patent Length Ligand Binding Domain Malignant neoplasm of prostate Mediating Metabolism Mus Mutagenesis Nucleoplasm PSA level Pathologic Peptides Proliferating Cell Nuclear Antigen Proteins RNA Splicing Receptor Signaling Recombinants Regulation Reporter Research Research Design Role Shapes Signal Transduction Stanolone Structure Testing Therapeutic Therapeutic Effect Variant advanced prostate cancer androgen deprivation therapy castration resistant prostate cancer cell growth cytotoxic cytotoxicity efficacious treatment inhibitor innovation knock-down monomer neoplastic cell non-oncogenic novel overexpression prognostic value prostate cancer cell prostate cancer model receptor receptor-mediated signaling recruit small molecule targeted treatment tumor tumor growth tumor xenograft

项目摘要

The overexpression of the full-length androgen receptor (AR-FL) and/or the constitutively active AR splicing variants (AR-Vs), such as AR-V7 and ARv567es lacking all or part of the ligand binding domain, contributes to the development and progression of castration resistant prostate cancers (CRPC). Androgen deprivation therapy (ADT) is not effective in CRPC overexpressing the AR-Vs and can even induce AR-V overexpression. Proliferating cell nuclear antigen (PCNA), preferentially overexpressed in all tumor cells, is a non-oncogenic protein essential for DNA replication and repair as well as cell growth and survival. Native PCNA is a ring-shaped homotrimer located mainly in the nucleoplasm. To be functional, PCNA must be linearized or monomerized for relocalization to chromatin, cytoplasm, or cell membrane, and serves as a platform for and executes its function through interaction with partner proteins containing the PCNA-interacting protein box (PIP-box) and other motifs. The PI’s group identified a consensus sequence of the PIP-box at the N-terminus of AR. PCNA complexes with AR-FL and AR-V7, which can be attenuated by a PIP-box-specific inhibitor T2AA. PCNA also binds to ARv567es and directly to recombinant AR protein. PCNA-I1S, a small molecule PCNA inhibitor developed by PI’s group, binds at the interface of two monomers, stabilizes trimer structure, and attenuates PCNA association to chromatin. PCNA-I1S and T2AA inhibit AR transcriptional activity and expression of AR target genes in CRPC LNCaP-AI and 22Rv1 cells. The knockdown expression of PCNA reduces dihydrotestosterone-stimulated AR transcriptional activity and abolishes the inhibitory effects of PCNA-I1S on AR activity. More importantly, an AR- specific PIP-box peptide inhibitor R9-AR-PIP, developed recently in the PI’s lab, binds to PCNA and inhibits AR transcriptional activity, expression of AR target genes, and growth of AR-positive cells. Based on these observations, the PI hypothesizes that PCNA interacts with AR-FL and AR-Vs through the AR PIP-box and enhances AR transcriptional activities and that targeting the PCNA-AR interaction will attenuate AR-FL- and AR-V-mediated signaling and inhibit growth of CRPC overexpressing AR-FL and/or AR-Vs. Two specific aims are proposed. Studies in aim 1 will further elucidate the role of the AR PIP-box in the interaction of AR-FL and AR-Vs with PCNA by protein mutagenesis and investigate the inhibitory effects of PCNA-I1S, T2AA, and R9-AR-PIP on the colocalization and chromatin association of PCNA with AR-FL and AR-Vs, the role of PCNA-AR interaction in recruitment of AR-FL and AR-Vs to chromatin, and the selective inhibitory effects of R- 9-AR-PIP on AR-PCNA interaction. Studies in aim 2 will determine the inhibitory effects of PCNA-I1S, T2AA, and R9-AR-PIP on the occupancy of the androgen response elements by AR-FL and AR-Vs, the transcriptional activity of AR-FL and AR-V7, and expression of AR-V-specific genes. Moreover, the cytotoxic effects of R9-AR- PIP on CRPC cells in culture, the therapeutic effects of R9-AR-PIP against CRPC xenograft tumors in mice, and the selective inhibitory effects of R9-AR-PIP on AR signaling in the CRPC tumors will be investigated.

全长雄激素受体 (AR-FL) 的过度表达和/或组成型活性 AR 剪接 (AR-Vs)，例如缺乏全部或部分配体结合结构域的 AR-V7 和 ARv567es，有助于去势抵抗性前列腺癌（CRPC）的发生和进展。 (ADT) 对于过度表达 AR-V 的 CRPC 无效，甚至可以诱导 AR-V 过度表达。增殖细胞核抗原 (PCNA) 在所有肿瘤细胞中优先过度表达，是一种非致癌物质 DNA 复制和修复以及细胞生长和存活所必需的蛋白质是一种环形。同源三聚体主要位于核质中，为了发挥功能，PCNA 必须线性化或单体化。重新定位到染色质、细胞质或细胞膜，并作为平台并执行其功能通过与含有 PCNA 相互作用蛋白盒 (PIP-box) 和其他基序的伙伴蛋白相互作用。 PI 团队在 PCNA 复合物的 N 末端确定了 PIP-box 的共有序列。 AR-FL 和 AR-V7 可以被 PIP 盒特异性抑制剂 T2AA 减弱，PCNA 也与 ARv567es 结合。并直接作用于重组PCNA-I1S，这是PI团队开发的一种小分子PCNA抑制剂，结合在两个单体的界面，稳定三聚体结构，并减弱 PCNA 与 PCNA-I1S 和 T2AA 抑制 CRPC 中 AR 转录活性和 AR 靶基因的表达。 LNCaP-AI 和 22Rv1 细胞 PCNA 的敲低表达减少二氢睾酮刺激的 AR。转录活性并消除 PCNA-I1S 对 AR 活性的抑制作用。 PI 实验室最近开发的特异性 PIP-box 肽抑制剂 R9-AR-PIP，可与 PCNA 结合并抑制 AR 转录活性、AR靶基因的表达以及AR阳性细胞的生长。根据观察，PI 爱好者发现 PCNA 通过 AR PIP-box 与 AR-FL 和 AR-V 进行交互，并且增强 AR 转录活性，并且靶向 PCNA-AR 相互作用将减弱 AR-FL- 和 AR-V 介导的信号传导并抑制过表达 AR-FL 和/或 AR-V 的 CRPC 的生长。提出了具体目标。目标 1 的研究将进一步阐明 AR PIP-box 在相互作用中的作用。 AR-FL 和 AR-Vs 与 PCNA 通过蛋白质诱变并研究 PCNA-I1S、T2AA、和 R9-AR-PIP 对 PCNA 与 AR-FL 和 AR-Vs 的共定位和染色质关联的影响， PCNA-AR 相互作用招募 AR-FL 和 AR-V 到染色质，以及 R-的选择性抑制作用 9-AR-PIP 对 AR-PCNA 相互作用的研究将确定 PCNA-I1S、T2AA、和 R9-AR-PIP 对 AR-FL 和 AR-V 占据雄激素反应元件的影响，转录 AR-FL 和 AR-V7 的活性以及 AR-V 特异性基因的表达此外，R9-AR- 的细胞毒性作用。 PIP 对培养的 CRPC 细胞的作用，R9-AR-PIP 对小鼠 CRPC 异种移植肿瘤的治疗作用，以及将研究 R9-AR-PIP 对 CRPC 肿瘤中 AR 信号传导的选择性抑制作用。