Ack1: A Critical Regulator of Hormone-Refractory Prostate Cancer

Ack1：激素难治性前列腺癌的关键调节因子

• 批准号: 8082792
• 负责人: Nupam P Mahajan
• 金额: $ 32.89万
• 依托单位: H. LEE MOFFITT CANCER CTR & RES INST
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-08 至 2015-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8082792
• 关键词: Ablation; Adenocarcinoma; Affect; Agar; Age; American; Amino Acids; Anchorage-Independent Growth; Androgen Antagonists; Androgen Receptor; Androgens; Antibodies; Applications Grants; Bicalutamide; Binding; Biological; Biological Assay; Cancer Etiology; Cancer Patient; Castration; Cells; Cessation of life; Data; Development; Disease; EGF gene; Enhancers; Event; Flutamide; Gene Expression; Gene Targeting; Genes; Genetic Transcription; Growth; Hormones; Implant; LAPC4; LNCaP; Ligands; Malignant - descriptor; Malignant neoplasm of prostate; Mediating; Molecular; Monitor; Mus; NKX3-1 gene; Neoplasms; Nude Mice; Patients; Phosphorylation; Phosphotransferases; Play; Premalignant; Prostate; Prostatic Intraepithelial Neoplasias; Protein Tyrosine Kinase; Pyrimidine; Receptor Activation; Receptor Protein-Tyrosine Kinases; Receptor Signaling; Refractory; Research Proposals; Resistance; Reverse Transcriptase Polymerase Chain Reaction; Role; Staging; Staining method; Stains; TMPRSS2 gene; Testing; Therapeutic; Tissue Microarray; Transactivation; Transcriptional Activation; Transgenic Mice; Tyrosine; Tyrosine Phosphorylation; Xenograft procedure; androgen independent prostate cancer; cell growth; deprivation; hormone refractory prostate cancer; inhibitor/antagonist; men; mouse model; pre-clinical; probasin; promoter; public health relevance; receptor expression; small molecule; tumor growth; tumor xenograft

DESCRIPTION (provided by applicant): Androgen receptor (AR) plays a critical role in progression of prostate cancer. We have recently demonstrated that Ack1 (also known as TNK2) regulates AR Tyr267-phosphorylation within the transactivation domain. While AR transcriptional activation by multiple tyrosine kinases is emerging as an alternate mode of AR activation, the precise role of Ack1 mediated AR Tyr267- phosphorylation in AR recruitment to the androgen responsive enhancers (ARE) and androgen-independent AR-responsive gene transcription is not fully understood. In this grant proposal we demonstrate that activated Ack1(pTyr284-Ack1) expression is upregulated as prostate cancer progresses and this activation is inversely correlated with the survival of prostate cancer patients. Since Ack1 regulates androgen-independent AR activity by its phosphorylation at Tyr267, we generated antibodies that specifically recognize pTyr267-AR. Neither pTyr267-AR expression nor its transcriptional activation was affected by anti-androgens e.g. bicalutamide/casodex and flutamide. However, a small molecule inhibitor of Ack1, 4-Amino-5,6- biaryl-furo[2,3-d]pyrimidine (YL3-026) not only inhibited Ack1 activation, but was able to suppress pTyr267-AR phosphorylation, binding to PSA, NKX3.1 and TMPRS2 promoters and inhibit AR transcription activity as seen by significant decrease in PSA gene expression. Our evidence indicates that targeting Ack1 kinase in prostate cancer patients could therefore be highly effective therapeutic strategy. In this proposal we will determine how AR Tyr267-phosphorylation regulates Androgen-Independent growth. Further, we will examine the ability of Ack1 inhibitor, YL3-026, to suppress androgen-independent transcription and xenograft tumor formation. Moreover, we will assess the ability of Ack1 inhibitor YL3-026 to suppress AR Tyr267-phosphorylation and prostatic intraepithelial neoplasia (PINs) formation in Prob-Ack1 transgenic mice. PUBLIC HEALTH RELEVANCE: A Hormone refractory prostate cancer is a significant cause of cancer death among American men. Here we demonstrate that that activated Ack1 expression is upregulated as prostate cancer progresses to androgen independence and this activation is inversely correlated with the survival of prostate cancer patients (n=267 patients). Using specific antibodies against Tyr267-phosphorylated AR (pTyr267-AR), we have shown that transcriptional activation of pTyr267-AR was unaffected by anti-androgens e.g. bicalutamide/casodex and flutamide. To precisely understand role of Ack1 in AR transcriptional activation in absence of androgens, we synthesized 4-Amino-5,6-biaryl-furo[2,3- d]pyrimidine (termed here as YL3-026). YL3-026 not only inhibited Ack1 activation, but was able to suppress pTyr267-AR phosphorylation, its binding to PSA, NKX3.1 and TMPRS2 promoters and inhibit AR transcription activity as seen by significant decrease in PSA gene expression. In this proposal we will identify a set of genes that are regulated by pTyr267-AR. Further, we shall assess effect of YL3-026 on formation of prostatic intraepithelial neoplasia in transgenic mice. Overall, this proposal would allow us to examine whether targeting Ack1 kinase in prostate cancer patients is an appropriate therapeutic strategy.

描述（由申请人提供）：雄激素受体（AR）在前列腺癌的进展中起着关键作用。我们最近证明 Ack1（也称为 TNK2）在反式激活域内调节 AR Tyr267 磷酸化。虽然多种酪氨酸激酶的 AR 转录激活正在作为 AR 激活的替代模式出现，但 Ack1 介导的 AR Tyr267-磷酸化在 AR 募集到雄激素反应增强子 (ARE) 和不依赖于雄激素的 AR 反应基因转录中的确切作用尚不明确。完全明白了。在这项拨款提案中，我们证明激活的 Ack1(pTyr284-Ack1) 表达随着前列腺癌的进展而上调，并且这种激活与前列腺癌患者的生存呈负相关。由于 Ack1 通过 Tyr267 磷酸化来调节雄激素非依赖性 AR 活性，因此我们生成了特异性识别 pTyr267-AR 的抗体。 pTyr267-AR 表达及其转录激活均不受抗雄激素的影响。比卡鲁胺/casodex 和氟他胺。然而，Ack1 的小分子抑制剂 4-氨基-5,6-联芳基-呋喃[2,3-d]嘧啶 (YL3-026) 不仅抑制 Ack1 激活，而且能够抑制 pTyr267-AR 磷酸化、结合PSA、NKX3.1 和 TMPRS2 启动子并抑制 AR 转录活性，如 PSA 基因表达显着下降所示。因此，我们的证据表明，针对前列腺癌患者的 Ack1 激酶可能是非常有效的治疗策略。在本提案中，我们将确定 AR Tyr267 磷酸化如何调节雄激素非依赖性生长。此外，我们将检查 Ack1 抑制剂 YL3-026 抑制雄激素非依赖性转录和异种移植肿瘤形成的能力。此外，我们将评估 Ack1 抑制剂 YL3-026 在 Prob-Ack1 转基因小鼠中抑制 AR Tyr267 磷酸化和前列腺上皮内瘤变 (PIN) 形成的能力。 公共卫生相关性：激素难治性前列腺癌是美国男性癌症死亡的一个重要原因。在这里，我们证明，随着前列腺癌进展到雄激素独立状态，激活的 Ack1 表达上调，并且这种激活与前列腺癌患者（n = 267 名患者）的生存呈负相关。使用针对 Tyr267 磷酸化 AR (pTyr267-AR) 的特异性抗体，我们发现 pTyr267-AR 的转录激活不受抗雄激素的影响。比卡鲁胺/casodex 和氟他胺。为了准确了解 Ack1 在没有雄激素的情况下 AR 转录激活中的作用，我们合成了 4-Amino-5,6-biaryl-furo[2,3-d]pyrimidine（此处称为 YL3-026）。 YL3-026 不仅抑制 Ack1 激活，而且能够抑制 pTyr267-AR 磷酸化、其与 PSA、NKX3.1 和 TMPRS2 启动子的结合，并抑制 AR 转录活性，如 PSA 基因表达显着降低所示。在本提案中，我们将鉴定一组受 pTyr267-AR 调控的基因。此外，我们将评估YL3-026对转基因小鼠中前列腺上皮内瘤变形成的影响。总体而言，该提案将使我们能够检查针对前列腺癌患者的 Ack1 激酶是否是一种合适的治疗策略。