Klotho介导IGF-1R/FOXO3a调控B细胞非霍奇金淋巴瘤发生发展的机制研究

B-cell non-Hodgkin lymphoma (B-NHL) is the most common subtype of NHL. Although targeted drugs and immunotherapy have significantly improved the prognosis of B-NHL patients, there are still approximately 1/3 of them present refractory or relapsed process. Klotho is an anti-aging gene which plays a significant role in aging and aging-related diseases. It was recently reported that Klotho involved in the development of several types of human malignancies. Our previous studies have demonstrated the aberrant expression of Klotho in B-NHL cell lines, however, the relevant mechanisms are still unclear. To further explore the anti-tumor function of Klotho and the potential strategies of targeted treatment, we aim to deeply investigate the expression and involved epigenetic mechanisms in B-NHL tissues, detect the effect of Klotho on the autophagy, proliferation, cell cycle, apoptosis and invasion of B-NHL cells, illuminate the regulation of Klotho on the IGF-1R/FOXO3a signaling aixs, and further elucidate the anti-tumor effect of Klotho and the main active form of recombinant Klotho protein by animal models. This study will identify the important role and the involved epigenetic variation of Klotho in the development and progression of B-NHL, and demonstrate the potential therapeutic value of recombinant Klotho protein. The finding of this study will provide novel theoretical and experimental basis to improve the prognosis of B-NHL.

尽管靶向药物及免疫治疗显著改善了B细胞淋巴瘤（B-NHL）的预后，但仍有约1/3的患者难治复发。抗衰老基因Klotho在衰老及衰老相关疾病中发挥重要作用，近来研究提示Klotho与多种恶性肿瘤的发生密切相关。我们前期实验发现Klotho在B-NHL中差异表达，但其确切机制尚待明确。为进一步探究Klotho在B-NHL中的抗肿瘤作用机制及靶向干预措施，本研究拟检测B-NHL中Klotho表达水平及其表观遗传学机制；探讨Klotho对B-NHL自噬、凋亡、侵袭的影响；结合生物信息学阐明Klotho对IGF-1R/FOXO3a的调控机制；体内验证重组Klotho蛋白的抗肿瘤作用及其主要活性形式。目的为阐明Klotho在B-NHL中差异表达的表观遗传学机制及其参与B-NHL发生发展的分子机制，揭示重组Klotho蛋白作为B-NHL潜在靶向治疗措施的可能性，为改善B-NHL的预后提供理论和实验依据。

尽管靶向药物及免疫治疗显著改善了B细胞淋巴瘤（B-NHL）的预后，但仍有约1/3的患者难治复发。基于分子的新型靶向药物开发为B-NHL整体预后的改善提供了新的机遇。前期研究发现长寿基因Klotho在B-NHL细胞株及弥漫大B细胞淋巴瘤（DLBCL）组织中表达显著降低，为进一步明确Klotho参与B-NHL发生发展的分子机制，本项目开展了Klotho的功能学验证及分子机制研究，为B-NHL的新型靶向治疗提供实验基础和科学依据。.主要研究内容包括Klotho调控IGF-1R参与DLBCL发生发展的具体机制，IGF-1R作为上游因子对Hippo/YAP信号通路的调控机制及阻断YAP表达在DLBCL中的抗肿瘤作用。.研究结果显示DLBCL患者Klotho低表达提示预后不良；靶向干预Klotho在体外可增加对阿霉素的化疗敏感性，在体内可显著抑制小鼠肿瘤生长；Klotho通过抑制DLBCL中IGF-1R信号通路的活化发挥抗肿瘤效应。IGF-1R抑制剂可抑制DLBCL细胞增殖及小鼠肿瘤生长；靶向抑制IGF-1R可显著下调YAP表达水平，并影响YAP蛋白的亚细胞表达，反之，IGF-1可通过激活IGF-1R诱导DLBCL中YAP的表达。靶向抑制YAP表达可显著抑制细胞增殖，诱导细胞凋亡及周期阻滞，增强化疗敏感性，在体内可发挥显著的抗肿瘤效应。.本项目探究了Klotho在B-NHL中的表达情况，及其作为B-NHL预后生物标记物及抗肿瘤治疗分子靶点的可能性；建立了B-NHL中以Klotho为核心的蛋白相互作用网络，阐明了Klotho调控IGF-1R参与DLBCL发生发展的具体机制，并发现IGF-1R可作为Hippo/YAP通路的上游调控分子参与DLBCL发生发展。研究结果揭示了Klotho、IGF-1R、YAP作为DLBCL治疗靶标的可行性，为NHL的分子靶向治疗提供了新的治疗靶点。