Sub-component for Institution # 16-01848 Novel moleculary targeted therapy of GBM

胶质母细胞瘤（GBM）患者预后不良。我们发现超过90%的GBM患者 过表达白细胞介素13受体α 2（IL-13 RA 2）和EphA 2受体，这在正常人中是不存在的。 个脑袋最近，我们已经证明EphA 3受体也在GBM中过表达，并且其表达与EphA 3受体的表达相关。 表达模式与EphA 2不同。IL-13 RA 2、EphA 2和EphA 3存在于多种细胞中。 GBM肿瘤的细胞。所有三种受体均在肿瘤核心的肿瘤细胞中表达， 局部浸润肿瘤细胞，而EphA 2也在肿瘤新生血管中过表达。此外，IL-13 RA 2， EphA 2和EphA 3与神经胶质瘤干细胞样细胞的病理生物学相关，并在其中发挥关键作用 （GSC）。IL-13 RA 2有助于GSC特性，并且EphA 2和EphA 3都驱动它们的自我更新， 致瘤性最后，EphA 3受体可以在单核细胞来源的GBM浸润细胞中容易地检测到， 肿瘤相关巨噬细胞（TAM）。因此，IL-13 RA 2、EphA 2和EphA 3共同表达于 主要GBM区室显示参与肿瘤进展和/或对治疗的抗性。之一 Eph受体配体ephrinA 5（eA 5）结合EphA 2和EphA 3，并且还独特地结合EphB 2受体; 后者也在GBM细胞上特异性表达。在当前的项目中，我们将追求一个新颖的想法， 用一种药物化合物靶向所有四种受体这种二价化合物将识别IL- 13 RA 2、EphA 2、EphA 3和EphB 2，并将药物递送至GBM肿瘤，特异性杀死肿瘤细胞和细胞 促进肿瘤生长的环境。我们还分离了一种小肽Pep-1 L， 特异性识别IL-13 RA 2，诱导受体内化，并与颅内肿瘤结合， 小鼠这些和其他性质使得肽成为增加药物/标记物接近的理想媒介物， 肿瘤的我们将通过两个具体目标继续这一令人兴奋的研究路线。在第一个目标中，我们将 产生同时靶向IL-13 RA 2、EphA 2、EphA 3和EphA 4的有效的二价细胞毒素QUAD-CTX， EphB 2受体。我们将产生具有修饰的化疗剂的化学缀合物，其可以通过免疫抑制剂。 血脑屏障（BBB），称为WP 1244。药物偶联物将在以下体外模型中进行测试： GBM和体内的各种隔室。在第二个目的中，我们将利用与IL-13 RA 2结合的肽， 有效的靶向全身或局部区域化疗，用于监测BBB的破坏， 对治疗的反应。我们将利用内化的肽Pep-1 L，它是颅内肿瘤的家园， 与WP 1244（Pep-1 L-CTX）偶联，并在表达IL-13 RA 2的GBM模型中对其进行测试，以验证偶联物的 穿透BBB和/或血脑肿瘤屏障的能力。我们还将生成成像探针的基础上， 肽。我们期望，这种对全球生物多样性的全面攻击将转化为明确的持久反应。 在病人身上。

Patients with glioblastoma (GBM) have a dismal prognosis. We found that over 90% of patients with GBM over-express both interleukin 13 receptor alpha 2 (IL-13RA2) and EphA2 receptor that are absent in normal brain. More recently, we have demonstrated that the EphA3 receptor is also over-expressed in GBM, and its pattern of expression differs from that of EphA2. IL-13RA2, EphA2, and EphA3 are present in various compartments of GBM tumors. All three receptors are expressed in tumor cells of the core of tumor and in locally-infiltrating tumor cells, while EphA2 is also over-expressed in tumor neovasculature. Further, IL-13RA2, EphA2, and EphA3 are associated with, and play crucial roles in, the pathobiology of glioma stem-like cells (GSC). IL-13RA2 contributes to GSC properties and EphA2 and EphA3 both drive their self-renewal and tumorigenicity. Finally, the EphA3 receptor can be readily detected in GBM-infiltrating cells of monocytic origin, tumor-associated macrophages (TAM). Thus, collectively, IL-13RA2, EphA2, and EphA3 are expressed in principal GBM compartments shown to be involved in tumor progression and/or resistance to therapies. One of the Eph receptor ligands, ephrinA5 (eA5), binds EphA2 and EphA3 and also uniquely the EphB2 receptor; the latter also is expressed specifically on GBM cells. In the current project, we will pursue the novel idea of targeting all four receptors with one pharmaceutical compound. This bi-valent compound will recognize IL- 13RA2, EphA2, EphA3, and EphB2 and deliver a drug to GBM tumors, specifically killing tumor cells and cells of the tumor environment promoting its growth. We have also isolated a small peptide, Pep-1L, which specifically recognizes IL-13RA2, induces receptor's internalization and it is bound by intracranial tumors in mice. These and other properties make the peptide a desirable vehicle to augment access of drugs/labels to tumors. We will continue this exciting line of research through two Specific Aims. In the first Aim, we will produce a potent bi-valent cytotoxin, QUAD-CTX, simultaneously targeting the IL-13RA2, EphA2, EphA3, and EphB2 receptors. We will generate a chemical conjugate with a modified chemotherapeutic which can pass the blood-brain barrier (BBB) on its own, termed WP1244. The drug conjugate will be tested in in vitro models of various compartments of GBM and in vivo. In the second Aim, we will exploit a peptide binding to IL-13RA2 for effective targeted systemic or loco-regional chemotherapy, for monitoring of the disruption of the BBB and responses to treatment. We will exploit internalized peptide Pep-1L, which homes to intracranial tumors, for conjugation to WP1244 (Pep-1L-CTX) and test it in GBM models expressing IL-13RA2 to verify the conjugate's ability to penetrate the BBB and/or blood-brain tumor barrier. We will also generate imaging probes based on the peptide. We expect that this comprehensive assault on GBM will translate into clear-cut durable responses in patients.