Biomedical Research Institute Sant Pau (IIB-Sant Pau), Hospital de la Santa Creu i Sant Pau, Barcelona Spain.
Josep Carreras Leukaemia Research Institute (IJC), Barcelona, Spain.
Theranostics. 2020 Apr 6;10(12):5169-5180. doi: 10.7150/thno.43231. eCollection 2020.
: Novel therapeutic strategies are urgently needed to reduce relapse rates and enhance survival in Diffuse Large B-Cell Lymphoma (DLBCL) patients. CXCR4-overexpressing cancer cells are good targets for therapy because of their association with dissemination and relapse in R-CHOP treated DLBCL patients. Immunotoxins that incorporate bacterial toxins are potentially effective in treating haematological neoplasias, but show a narrow therapeutic index due to the induction of severe side effects. Therefore, when considering the delivery of these toxins as cancer therapeutics, there is a need not only to increase their uptake in the target cancer cells, and their stability in blood, but also to reduce their systemic toxicity. We have developed a therapeutic nanostructured protein T22-PE24-H6 that incorporates exotoxin A from which selectively targets lymphoma cells because of its specific interaction with a highly overexpressed CXCR4 receptor (CXCR4) in DLBCL. : T22-PE24-H6 cytotoxicity and its dependence on the CXCR4 receptor were evaluated in DLBCL cell lines using cell viability assays. Different experiments (mitochondrial membrane potential, Western Blot, Annexin V and DAPI staining) were conducted to determine T22-PE24-H6 cell death mechanisms. imaging and therapeutic effect studies were performed in a disseminated DLBCL mouse model that mimics organ infiltration in DLBCL patients. Finally, immunohistochemistry and histopathology analyses were used to evaluate the antineoplastic effect and systemic toxicity. : T22-PE24-H6 induced selective cell death of CXCR4 DLBCL cells by activating the apoptotic pathway. In addition, repeated T22-PE24-H6 intravenous administration in a CXCR4 DLBCL-disseminated mouse model showed a significant reduction of lymphoma burden in organs clinically affected by DLBCL cells (lymph nodes and bone marrow). Finally, we did not observe systemic toxicity associated to the nanoparticle treatment in non-DLBCL-infiltrated organs. : We have demonstrated here a potent T22-PE24-H6 antineoplastic effect, especially in blocking dissemination in a CXCR4 DLBCL model without associated toxicity. Thereby, T22-PE24-H6 promises to become an effective alternative to treat CXCR4 disseminated refractory or relapsed DLBCL patients.
: 迫切需要新的治疗策略来降低弥漫性大 B 细胞淋巴瘤 (DLBCL) 患者的复发率并提高生存率。由于 CXCR4 过表达的癌细胞与 R-CHOP 治疗的 DLBCL 患者的扩散和复发有关，因此它们是治疗的理想靶点。结合细菌毒素的免疫毒素在治疗血液系统恶性肿瘤方面具有潜在的有效性，但由于诱导严重的副作用，其治疗指数较窄。因此，在考虑将这些毒素作为癌症治疗药物进行递送时，不仅需要增加它们在靶癌细胞中的摄取率及其在血液中的稳定性，还需要降低其全身毒性。我们已经开发了一种治疗性纳米结构蛋白 T22-PE24-H6，它包含来自的外毒素 A，由于其与 DLBCL 中高度过表达的 CXCR4 受体 (CXCR4) 的特异性相互作用，因此选择性地靶向淋巴瘤细胞。: 在 DLBCL 细胞系中，通过细胞活力测定评估 T22-PE24-H6 的细胞毒性及其对 CXCR4 受体的依赖性。进行了不同的实验（线粒体膜电位、Western Blot、Annexin V 和 DAPI 染色）来确定 T22-PE24-H6 的细胞死亡机制。在模拟 DLBCL 患者器官浸润的播散性 DLBCL 小鼠模型中进行了成像和治疗效果研究。最后，使用免疫组织化学和组织病理学分析评估抗肿瘤作用和全身毒性。: T22-PE24-H6 通过激活凋亡途径诱导 CXCR4 DLBCL 细胞的选择性细胞死亡。此外，在 CXCR4 DLBCL 播散性小鼠模型中重复进行 T22-PE24-H6 静脉给药，显示出在受 DLBCL 细胞影响的临床器官（淋巴结和骨髓）中淋巴瘤负担显著减少。最后，我们在未浸润 DLBCL 的器官中未观察到与纳米颗粒治疗相关的全身毒性。: 我们在这里证明了 T22-PE24-H6 具有强大的抗肿瘤作用，特别是在阻止 CXCR4 DLBCL 模型中的扩散而没有相关毒性的情况下。因此，T22-PE24-H6 有望成为治疗 CXCR4 播散性难治性或复发性 DLBCL 患者的有效替代方法。
