Targeting GCNT3 for Pancreatic Cancer

总结 胰腺癌（PC）是所有癌症中死亡率最高的，5年生存率不到10%。 尽管靶向治疗的发展取得了进展，但存活率仍然低得令人无法接受。是的， 因此，重要的是要确定新的治疗方法，可以导致更有效的治疗， 这种恶性疾病。该提议探索了核心2粘蛋白合成基因GCNT 3的新概念， 调节PC的生长和存活，赋予GCNT 3新的关键作用。我们已经证明GCNT 3 GCNT 3在PC患者中过表达，并参与PC发病机制，表明GCNT 3是一种有前途的 治疗靶点然而，GCNT 3如何调节PC尚不清楚。使用计算机小分子对接 通过模拟方法，我们发现他尼氟酯是一种选择性结合GCNT 3的新型抑制剂。 通过研究GCNT 3介导的PC生长的分子机制，我们发现siRNA介导的PC生长的分子机制与GCNT 3介导的PC生长的分子机制无关。 敲低GCNT 3或用他尼氟酯处理抑制异种移植肿瘤。他尼氟酯也降低了 GCNT 3表达，导致体内和体外粘蛋白的产生减少，并改善细胞增殖。 吉西他滨摄取。综上所述，我们的研究结果强烈表明，靶向粘蛋白的生物合成，通过 GCNT 3可以改善对药物治疗的反应性。 因此，我们假设GCNT 3的异常表达将导致粘蛋白的过度合成 在PC的发展过程中，并导致耐药性。因此，异常粘蛋白合成的抑制是 足以破坏粘蛋白网的屏障性质， 化疗药物的靶点。提出了三个独立但相互关联的具体目标，以解决 这个假设。目的1：产生GCNT 3缺陷型KPC小鼠并确定靶向GCNT 3是否消除 粘蛋白屏障，并通过增加吉西他滨和白蛋白结合型紫杉醇（NPT）抑制PC进展/转移 功效目的2：确定他尼氟酯联合NPT治疗PC是否有效 通过a）在临床上评估体内施用的组合的功效和剂量反应效应， 自发性PC的相关KPC模型和B）测定粘蛋白破坏和吉西他滨或NPT摄取 联合治疗的肿瘤。c）我们将建立肿瘤组织中的GCNT 3和NPT水平及其在肿瘤组织中的表达。 通过全基因组转录组与粘蛋白亚型（Mucs）和PC治疗疗效的相关性 测序和PET成像。目的3：我们将研究GCNT 3在吉西他滨耐药中的作用， 过表达和PC生长。a）对于临床相关性，我们将评估人类患者的抑制- 衍生的异种移植物（PDX）和PC切片培养物。B）评价以下药物的疗效 本发明提供了用于体内抗过表达GCNT 3的人PC PDX肿瘤的组合。 退伍军人健康相关性：胰腺癌的主要健康问题和许多退伍军人及其 家庭遭受这种肿瘤疾病。这项研究的结果将产生重大影响，因为 他们将阐明未来发展的新的治疗策略的PC。因此，这一建议高度 翻译性质

Summary Pancreatic cancer (PC) has the highest mortality of any cancer, with a 5-year survival rate of less than 10%. Despite progress in the development of targeted therapies, the survival rate is still unacceptably low. It is, therefore, important to identify novel therapeutic approaches that could lead to a more effective treatment for this malignant disease. This proposal explores the novel concept that a core 2 mucin synthesis gene, GCNT3, regulates PC growth and survival, ascribing a new and critical role to GCNT3. We have shown that GCNT3 is overexpressed in PC patients and contributes to PC pathogenesis, indicating that GCNT3 is a promising therapeutic target. However, how GCNT3 regulates PC is not clear. Using in silico small molecular docking simulation approaches, we discovered that talniflumate is a novel inhibitor that selectively binds to GCNT3. Examining the molecular mechanisms of GCNT3-mediated PC growth, we found that siRNA-mediated knockdown of GCNT3 or treatment with talniflumate, inhibited xenograft tumors. Talniflumate also reduced GCNT3 expression, leading to reduced production of mucins in vivo and in vitro, and improved cellular gemcitabine uptake. Taken together, our findings strongly suggest that targeting mucin biosynthesis through GCNT3 may improve responsiveness to drug treatment. We, therefore, hypothesize that aberrant expression of GCNT3 will lead to excessive mucin synthesis during PC development and cause chemoresistance. Hence, the inhibition of aberrant mucin synthesis is sufficient to disrupt the barrier properties of the mucin mesh to efficiently increase the access of chemotherapeutics to target sites. Three independent, yet interrelated, specific aims are proposed to address this hypothesis. Aim 1: Generate GCNT3-deficient KPC mice and determine whether targeting GCNT3 ablates the mucin barrier and inhibits PC progression/metastasis by increasing gemcitabine and nab-paclitaxel (NPT) efficacy. Aim 2: Determine whether combinational therapy of talniflumate plus NPT are effective in treating PC by a) evaluating the efficacy and dose-response effects of the combination administered in vivo in a clinically relevant KPC model of spontaneous PC and b) determining mucin disruption and gemcitabine or NPT uptake in combination-treated tumors. c) We will establish the GCNT3 and NPT levels in tumor tissue and their correlation with mucin subtypes (Mucs) and PC treatment efficacy via whole genome transcriptome sequencing and PET imaging. Aim 3: We will investigate the role of GCNT3 in gemcitabine resistance, mucin overexpression and PC growth. a) For clinical relevance, we will assess the inhibition of human patient- derived xenografts (PDX) and PC slice cultures by combinational therapy. b) Evaluate the efficacy of combination against GCNT3 overexpressing human PC PDX tumors in vivo. Veterans Health Relevance: Pancreatic cancer major health problem and many veterans and their families suffered from this neoplastic disease. The results obtained from this study will have high impact, since they will shed light on future development of novel therapeutic strategies for PC. Thus, this proposal is highly translational in nature