Engineering Biomaterials to Modulate the Bone Marrow Microenvironment in Multiple Myeloma

项目总结 多发性骨髓瘤(MM)约占所有血液系统恶性肿瘤的23%，占癌症相关死亡的2.1% 2022年在美国。尽管为开发有效的治疗方法付出了巨大的努力，但MM在很大程度上仍然 无法治愈，而且几乎所有的患者都对目前的治疗产生了抵抗力。因此，临床上存在着迫切的需求。 用于创新和改进的多发性骨髓瘤疗法。已有研究表明，骨髓内皮细胞是至关重要的。 多发性骨髓瘤细胞归巢、进展、存活和耐药性。具体地说，亲环素A和E-选择素 归巢因子和黏附受体分别由骨髓内皮细胞表达，对 Mm存活期。因此，抑制亲环素A和E-选择素提供了一种潜在的治疗策略来废除 MM的传播和抵抗。然而，亲环素A和E-选择素的直接和特异性抑制 小分子一直难以捉摸。因此，亲环素A和E-选择素是很有前途的组合候选者 RNA干扰(RNAi)疗法，通过直接减少传统上不可药物的靶点 信使核糖核酸(MRNA)的表达。利用小干扰RNA(SiRNA)的挑战是需要 安全有效的给药方法，因为siRNA在血液中降解，不容易通过 膜。在我的博士前研究期间，我设计了一个聚合物-脂质杂化生物材料库， 与聚乙二醇脂结物和siRNA结合，组装成纳米颗粒(NPs) 通过微流控混合。通过体内高通量筛选，我确定了一种具有有效基因的NP配方 体内骨髓内皮细胞沉默。该制剂用于包裹亲环素A siRNA， 并在体内表现出抑制MM进展的作用，并使MM细胞对蛋白酶体抑制剂Bortezomib增敏， 目前治疗多发性骨髓瘤的一种治疗方法。在F99阶段，我将改进我们的NP设计，包括 NP表面的骨髓内皮靶向配体增强其对骨髓的特异性 内皮，最大限度地减少偏离目标的影响。我将使用我们的靶向NP共包裹亲环素A和E- 选择素siRNA序列，并通过黏附和跨内皮细胞迁移评价其体外抑制作用 测定MM细胞的侵袭能力。此外，我将测试我们共同交付的siRNA纳米技术 通过在经过验证的MM小鼠异种移植模型中进行存活研究，并量化其单独或 与波特佐米联合使用。这项技术有望为目标用户提供一个广泛的支持平台 其他与骨髓有关的癌症。对于K00阶段，我将找到一家著名的癌症生物实验室来 用高维单细胞研究骨髓免疫微环境中的细胞-细胞相互作用 方法和组织工程模型，目的是确定推动癌症进展的机制 以及抗药性。这个项目的完成将成功地为我启动NIH资助的研究做好准备 专注于针对肿瘤微环境的药物输送作为癌症治疗手段的实验室。

PROJECT SUMMARY Multiple myeloma (MM) accounts for ~23% of all hematologic malignancies with a 2.1% of cancer-related deaths in the United States in 2022. Despite tremendous efforts to develop effective therapies, MM remains largely incurable, and virtually all patients develop resistance to current therapies. Thus, there is an urgent clinical need for innovative and improved MM therapeutics. It has been demonstrated that bone marrow endothelium is critical to MM cell homing, progression, survival, and drug resistance. Specifically, cyclophilin A and E-selectin, a homing factor and adhesion receptor, respectively, expressed by bone marrow endothelial cells, are critical to MM survival. Thus, inhibition of cyclophilin A and E-selectin provides a potential therapeutic strategy to abolish MM dissemination and resistance. However, direct- and specific-inhibition of cyclophilin A and E-selectin by small molecules has been elusive. Thus, cyclophilin A and E-selectin are promising candidates for combination RNA interference (RNAi) therapy, which inhibits traditionally undruggable targets by directly reducing their messenger RNA (mRNA) expression. The challenge of utilizing small-interfering RNA (siRNA) is the need for safe and effective delivery methods, as siRNA degrades in the bloodstream and does not readily cross membranes. During my predoctoral studies, I have engineered a library of polymer-lipid hybrid biomaterials, that in combination with polyethylene glycol (PEG)-lipid conjugates and siRNA, assembled into nanoparticles (NPs) via microfluidic mixing. Through high-throughput in vivo screening, I identified a NP formulation with potent gene silencing in bone marrow endothelial cells in vivo. This formulation was used to encapsulate cyclophilin A siRNA, and showed inhibition of MM progression in vivo, and sensitized MM cells to the proteasome inhibitor bortezomib, a current therapeutic modality to treat MM. During the F99 phase, I will improve our NP design by incorporating bone marrow endothelial-targeting ligands on the NP’s surface to enhance their specificity to bone marrow endothelium, minimizing off-target effects. I will use our targeted NP to co-encapsulate cyclophilin A and E- selectin siRNA sequences, and evaluate their inhibition in vitro through adhesion and transendothelial migration assays, to determine the invasive abilities of MM cells. Further, I will test our co-delivery siRNA nanotechnology through a survival study in a validated mouse xenograft model of MM and quantify its effects either alone or in combination with bortezomib. This technology is expected to provide with a broadly enabling platform to target other bone marrow-homing cancers. For the K00 phase, I will identify a renowned cancer biology laboratory to study cell-cell interactions in the bone marrow immune microenvironment utilizing high-dimensional single-cell approaches and tissue-engineered models, with the aim to determine mechanisms that drive cancer progression and drug resistance. Completion of this project will successfully prepare me to launch an NIH-funded research laboratory that focuses on drug delivery targeting the tumor microenvironment as means of cancer therapy.