Non-canonical Wnt-Receptor Signaling and Targeted Therapies

ROR1是Wnt5a的受体，它可以诱导非规范的Wnt信号，激活Rho GTP酶，以及 增强白血病细胞的迁移、增殖和存活率。ROR1的高水平表达可加速 转基因小鼠模型中白血病的发生发展及其与更具侵袭性的相关性 疾病和CLL患者较短的生存期(PTS)。CLL细胞也表达其他发育受限的 Wnt5A受体，即ROR2和RYK，在CLL中参与非典型的Wnt信号转导。我们 假设阐明ROR1、ROR2和ROR2参与信号传递的结构-功能-关系 Ryk将定义非规范Wnt信号的临床相关生物标记物，并确定新的靶点 心理治疗。此外，抑制非规范的Wnt信号可能有治疗应用，或者单独 或与其他新开发的靶向治疗相结合，抑制B细胞受体信号转导或bcl2。 为此，我们有以下具体的目标：(目标1)询问非规范的信号转导途径 CLL中的WNT受体-我们将定义与Wnt5a反应而招募到ROR1/2的蛋白，并确定 信令所需的结构域。我们将研究RYK对Wnt5a信号的贡献 确定SH3结合蛋白14-3-3ζ或钙/钙调蛋白(CaM)依赖的蛋白激酶的作用 II(CaMKII)在ROR1依赖的信号转导中的作用，并研究ROR1K对非-ROR1信号通路的贡献和作用 规范的WNT信号。(目标2)检测CLL细胞中非典型Wnt受体的共表达 并测定WNT信号的相对水平-我们将检测CLL患者的血液样本 对血浆Wnt5a有高、低或可忽略的ROR1表达的细胞，白血病细胞表达 ROR2和RYK，以及规范和非规范Wnt信号的白血病细胞激活。我们也会 为新描述的茎指数检查选定的CLL样本和细胞系的转录本， 这依赖于ROR1信号。我们还将检查典型的β-连环蛋白之间的串扰- 依赖的Wnt信号通路和非规范的、β不依赖的连环蛋白通路，这可能是 受ROR1、ROR2或RYK相对表达的影响，或受新产生的单抗处理的影响 特定于ROR2或RYK。(目标3)研究ROR1信号转导通路在糖尿病的发生发展中的作用 CLL对靶向治疗的耐药性-我们将检测ROR1，ROR2， 从PTS采集的连续CLL样本中的RYK和RYK 靶向治疗并评估Cirmtuzumab和bcl2拮抗剂之间的协同作用潜力， 维尼托克拉克斯。

ROR1 is a receptor for Wnt5a, which can induce non-canonical Wnt-signaling, activate Rho GTPases, and enhance leukemia-cell migration, proliferation, and survival. High-level expression of ROR1 can accelerate development and progression of leukemia in transgenic mouse models and associates with more aggressive disease and shorter survival of patients (pts) with CLL. CLL cells also express other developmentally-restricted Wnt5a-receptors, namely ROR2 and RYK, which can contribute to non-canonical Wnt-signaling in CLL. We hypothesize that elucidation of the structure-function-relationships involved in signaling by ROR1, ROR2, and RYK will define clinically relevant biomarkers for non-canonical Wnt-signaling and identify novel targets for therapy. Moreover, inhibition of non-canonical Wnt-signaling could have therapeutic applications, either alone or in combination with other newly developed targeted therapies that inhibit B-cell-receptor-signaling or BCL2. For this, we have the following specific aims: (AIM 1) Interrogate the signaling-pathways of non-canonical Wnt receptors in CLL - We will define the proteins recruited to ROR1/2 in response to Wnt5a and determine the structural domains required for signaling. We will examine the contribution of RYK to Wnt5a-signaling in CLL, determine the role of SH3-binding proteins, 14-3-3ζ, or Ca2+/calmodulin (CaM)-dependent protein kinase II (CaMKII) in ROR1-dependent signaling, and examine the contribution and function of ROR1 kinase to non- canonical Wnt-signaling. (AIM 2) Examine CLL cells for co-expression of non-canonical Wnt-receptors and determine the relative levels of Wnt-signaling - We will examine the blood samples of pts with CLL cells that have high, low, or negligible expression of ROR1 for plasma Wnt5a, leukemia-cell expression of ROR2 and RYK, and for leukemia-cell activation of canonical and non-canonical Wnt signaling. We also will examine the transcriptomes of selected CLL samples and cell lines for the newly described stemness index, which is dependent on ROR1-signaling. We also will examine for cross-talk between the canonical β-catenin- dependent Wnt-signaling pathway and the non-canonical, β-catenin-independent pathway, which may be influenced by the relative expression of ROR1, ROR2, or RYK, or by treatment with newly generated mAbs specific for ROR2 or RYK. (AIM 3) Examine the contribution of ROR1-signaling to the development of resistance to targeted therapies in CLL - We will examine expression-levels and function of ROR1, ROR2, and RYK in serial CLL samples collected from pts before, during, and after development of resistance to targeted therapies and evaluate the potential for synergy between cirmtuzumab and the BCL2 antagonist, venetoclax.