文章：

KLC1-ROS1融合基因通过特异性激活JAK-STAT通路发挥胶质瘤细胞的致癌特性

KLC1-ROS1 Fusion Exerts Oncogenic Properties of Glioma Cells via Specific Activation of JAK-STAT Pathway

原文发布日期：19 December 2023

DOI: 10.3390/cancers16010009

类型: Article

开放获取: 是

英文摘要：

Here, we investigated the detailed molecular oncogenic mechanisms of a novel receptor tyrosine kinase (RTK) fusion,KLC1-ROS1, with an adapter molecule, KLC1, and an RTK, ROS1, discovered in pediatric glioma, and we explored a novel therapeutic target for glioma that possesses oncogenic RTK fusion. When wild-typeROS1andKLC1-ROS1fusions were stably expressed in the human glioma cell lines A172 and U343MG, immunoblotting revealed thatKLC1-ROS1fusion specifically activated the JAK2-STAT3 pathway, a major RTK downstream signaling pathway, when compared with wild-typeROS1. Immunoprecipitation of the fractionated cell lysates revealed a more abundant association of the KLC1-ROS1 fusion with JAK2 than that observed for wild-type ROS1 in the cytosolic fraction. A mutagenesis study of the KLC1-ROS1 fusion protein demonstrated the fundamental roles of both the KLC1 and ROS1 domains in the constitutive activation of KLC1-ROS1 fusion. Additionally, in vitro assays demonstrated that KLC1-ROS1 fusion upregulated cell proliferation, invasion, and chemoresistance when compared to wild-type ROS1. Combination treatment with the chemotherapeutic agent temozolomide and an inhibitor of ROS1, JAK2, or a downstream target of STAT3, demonstrated antitumor effects against KLC1-ROS1 fusion-expressing glioma cells. Our results demonstrate that KLC1-ROS1 fusion exerts oncogenic activity through serum-independent constitutive activation, resulting in specific activation of the JAK-STAT pathway. Our data suggested that molecules other than RTKs may serve as novel therapeutic targets for RTK fusion in gliomas.

摘要翻译： 

本研究深入探讨了在儿童胶质瘤中发现的一种新型受体酪氨酸激酶（RTK）融合基因KLC1-ROS1的详细分子致癌机制，该融合基因由衔接分子KLC1与RTK分子ROS1构成，并探索了携带致癌性RTK融合的胶质瘤治疗新靶点。在人胶质瘤细胞系A172和U343MG中稳定表达野生型ROS1与KLC1-ROS1融合蛋白后，免疫印迹分析显示，与野生型ROS1相比，KLC1-ROS1融合蛋白特异性激活了JAK2-STAT3通路——这是RTK下游的主要信号传导途径。通过对分级细胞裂解物进行免疫共沉淀，发现KLC1-ROS1融合蛋白在胞质组分中与JAK2的结合量显著高于野生型ROS1。对KLC1-ROS1融合蛋白的突变研究表明，KLC1结构域和ROS1结构域均对该融合蛋白的组成性激活起关键作用。此外，体外实验证实，与野生型ROS1相比，KLC1-ROS1融合蛋白可上调细胞增殖、侵袭能力和化疗耐药性。联合使用化疗药物替莫唑胺与ROS1抑制剂、JAK2抑制剂或STAT3下游靶点抑制剂，对表达KLC1-ROS1融合蛋白的胶质瘤细胞显示出抗肿瘤效应。我们的研究结果表明，KLC1-ROS1融合蛋白通过不依赖血清的组成性激活发挥致癌活性，并特异性激活JAK-STAT通路。本研究表明，除RTK本身外，其他分子也可能成为胶质瘤中RTK融合的新型治疗靶点。

原文链接：

KLC1-ROS1 Fusion Exerts Oncogenic Properties of Glioma Cells via Specific Activation of JAK-STAT Pathway