PO.ET02.08 · 实验与分子治疗
脂聚合物介导的融合癌基因靶向siRNA递送在血液系统恶性肿瘤临床前模型中减轻白血病负荷并改善生存
Lipopolymer-mediated delivery of fusion oncogene-targeting siRNAs attenuates leukemia burden and improves survival in preclinical models of hematologic malignancies
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
血液系统恶性肿瘤是遗传学上高度异质性的癌症，以一系列染色体易位为特征，其中融合癌基因，例如急性淋巴细胞白血病（ALL）中的KMT2A::AFF1、急性髓系白血病（AML）中的KMT2A::MLLT3以及慢性髓系白血病（CML）中的BCR::ABL1，尤为侵袭性强且临床上难以治疗。这些融合驱动的血液系统恶性肿瘤与不良预后和对传统疗法的耐药相关，凸显了对融合靶向、个体化治疗策略的需求。小干扰RNA（siRNAs）因其精确基因沉默的能力而提供了一种有前景的方法。然而，其临床转化受到递送挑战的阻碍，包括快速降解、脱靶效应、肝脏蓄积以及造血细胞摄取效率低下，这在很大程度上是由于其负电荷、尺寸以及血细胞有限的胞质体积所致。
为解决这些局限，我们通过将脂肪族脂质偶联到低分子量聚乙烯亚胺（PEI，1.2 kDa）上，开发了一种新型基于脂聚合物的siRNA递送平台。这种修饰产生了一系列能够与siRNAs形成稳定纳米复合物的脂聚合物，通俗称为脂聚合物/siRNA纳米颗粒（LPNPs）。这些LPNPs利用PEI的阳离子特性进行siRNA结合，并利用脂质介导的机制来增强细胞摄取。我们分别在ALL、AML和CML的临床前模型中评估了LPNPs递送靶向KMT2A::AFF1、KMT2A::MLLT3和BCR::ABL1的siRNAs的疗效。
LPNP介导的递送在所有三种白血病细胞系中实现了高效的胞内siRNA摄取和强大的基因沉默，从而显著下调融合癌基因的表达。这种沉默诱导了凋亡并在体外显著降低了集落形成潜力。体内生物分布研究表明，LPNPs在白血病伴随组织（包括骨髓和脾脏）中的生物分布增强，同时肝脏滞留减少。尤为重要的是，全身给予LPNPs导致白血病负荷大幅降低，并在ALL、AML和CML的异种移植模型中显著改善生存。
我们的研究结果凸显了脂聚合物介导的siRNA递送在靶向血液系统恶性肿瘤融合癌基因方面的治疗潜力。该平台为克服当前的递送障碍、推进基于RNA干扰的疗法迈向临床应用提供了一种有前景的策略。
查看英文原文 English abstract
Hematologic malignancies are genetically heterogeneous cancers marked by a range of chromosomal translocations, among which fusion oncogenes, e.g., KMT2A::AFF1 in acute lymphoblastic leukemia (ALL), KMT2A::MLLT3 in acute myeloid leukemia (AML), and BCR::ABL1 in chronic myeloid leukemia (CML), are particularly aggressive and clinically intractable. These fusion-driven hematologic malignancies are associated with poor prognosis and resistance to conventional therapies, emphasizing the need for fusion targeted, personalized treatment strategies. Small interfering RNAs (siRNAs) offer a promising approach due to their capacity for precise gene silencing. However, clinical translation is hindered by delivery challenges, including rapid degradation, off-target effects, hepatic accumulation, and inefficient uptake by hematopoietic cells, largely due to their negative charge, size, and the limited cytoplasmic volume of blood cells.
To address these limitations, we developed a novel lipopolymer-based siRNA delivery platform by conjugating aliphatic lipids onto low-molecular-weight polyethyleneimine (PEI, 1.2 kDa). This modification yielded a series of lipopolymers capable of forming stable nanocomplexes with siRNAs, colloquially known as lipopolymer/siRNA nanoparticles (LPNPs). These LPNPs leverage the cationic nature of PEI for siRNA binding and lipid-mediated mechanisms to enhance cellular uptake. We evaluated the efficacy of LPNPs in delivering siRNAs targeting KMT2A::AFF1 , KMT2A::MLLT3 , and BCR::ABL1 in preclinical models of ALL, AML, and CML, respectively.
LPNP-mediated delivery attained efficient intracellular siRNA uptake and robust gene silencing in all three forms of leukemia cell lines, which resulted significant downregulation of fusion oncogene expression. This silencing induced apoptosis and markedly reduced colony-forming potential in vitro . In vivo biodistribution studies demonstrated enhanced biodistribution of LPNPs in leukemia-accompanying tissues, including bone marrow and spleen, with reduced hepatic sequestration. Particularly, systemic administration of LPNPs led to a substantial reduction in leukemia burden and significantly improved survival in xenograft models of ALL, AML, and CML.
Our findings highlight the therapeutic potential of lipopolymer-mediated siRNA delivery for targeting fusion oncogenes in hematologic malignancies. This platform offers a promising strategy for overcoming current delivery barriers and advancing RNA interference-based therapies toward clinical application.
利益披露 Disclosure
M. Nasrullah, None.
R. Kc,
RJH Biosciences Inc. Employment, Stock.
O. Heidenreich, None..
J. Brandwein, None.
H. Uludag,
RJH Biosciences Inc. Employment, Stock.