LPD Nanoparticles in Anti-Cancer Therapy

描述（由申请人提供）：我们最近开发了一种茴香酰胺靶向纳米颗粒制剂，称为LPD，用于在无胸腺裸鼠模型中将siRNA静脉内递送至人肺癌细胞NCI-H460（表达σ受体）。该siRNA旨在沉默表皮生长因子受体（EGFR）。由于肿瘤的高水平摄取（70-80%注射剂量/g组织），EGFR在整个肿瘤中完全沉默。尽管siRNA的高效递送和靶癌基因的沉默，但肿瘤细胞在体内仅显示部分（~15%）凋亡和部分生长抑制。因此，该项目将开发几种独立的策略来增强LPD介导的治疗活性。在目标1中，我们将包封多组靶向不同细胞癌基因的siRNA，以显示至少一种相加（如果不是协同的话）的肿瘤杀伤作用。Let-7 miRNA也将在模型中测试其肿瘤抑制活性。还将测试化学修饰的siRNA（包括含有硼烷基磷酸酯的那些）的延长沉默效果。我们已经发现阳离子脂质DOTAP（其是LPD制剂中的主要组分）显示出保护肿瘤细胞免于死亡的抗凋亡活性。我们已经发现了另一种阳离子脂质，其本身杀死肿瘤细胞，并可用于替代siRNA制剂中的DOTAP。初步数据表明，茴香酰胺靶向的LPD也可以将siRNA递送至小鼠黑色素瘤B16 F10细胞的肺转移。目的2：利用不同的siRNA诱导小鼠黑色素瘤细胞凋亡。我们还将测试剪接移位寡核苷酸，其将抗凋亡Bcl-xL转化为凋亡Bcl-xS以诱导肿瘤细胞死亡。由于递送系统还可以递送质粒DNA沿着siRNA，因此不同的抗癌基因可以用于与siRNA的联合治疗。在目标3中，我们将采用另一种纳米颗粒制剂，即，LPH含有硫酸肝素，可单独或与EGFR siRNA一起递送多柔比星（dox），这是一种有效的抗癌药物。由于dox和EGFR沉默通过不同的机制诱导细胞凋亡，我们预计至少有一个累加效应，如果不是协同效应。Dox将与硫酸肝素化学结合，并在LPH中共同配制。该项目的目标是开发用于癌症治疗的高效抗肿瘤纳米颗粒剂。公共卫生相关性：该项目的目标是开发用于癌症治疗的siRNA的肿瘤特异性全身递送系统。自组装纳米颗粒制剂将用作递送载体。该项目使用小鼠肺癌和肺转移作为疾病模型。

DESCRIPTION (provided by applicant): We have recently developed an anisamide-targeted nanoparticle formulation, called LPD, for intravenous delivery of siRNA to human lung cancer cells NCI-H460 (expressing the sigma receptor) in an athymic nude mouse model. The siRNA was designed to silence the epidermal growth factor receptor (EGFR). As the result of a high level of uptake by the tumor (70-80% injected dose per g of tissue), the EGFR was completely silenced through out the entire tumor. Despite the high efficiency delivery of the siRNA and silencing of the target oncogene, the tumor cells only showed a partial (~15%) apoptosis and partial growth inhibition in vivo. Thus, the project will develop several independent strategies to enhance the therapeutic activity mediated by LPD. In aim 1, we will encapsulate multiple sets of siRNA targeting to different cellular oncogenes to show at least an additive, if not synergistic, effect in tumor killing. Let-7 miRNA will also be tested for its tumor suppression activity in the model. Chemically modified siRNA including those containing boranophosphate will also be tested for prolonged silencing effect. We have discovered that cationic lipid DOTAP, which is a major component in the LPD formulation, shows an anti-apoptotic activity which protects the tumor cells from death. We have discovered another cationic lipid which by itself kills tumor cells and can be used to replace DOTAP in the siRNA formulation. Preliminary data indicate that the anisamide targeted LPD can also deliver siRNA to the pulmonary metastasis of mouse melanoma B16F10 cells. In aim 2, we will deliver different siRNA to induce apoptosis of the melanoma cells in mice. We will also test a splice shifting oligo which will convert the anti-apoptotic Bcl-xL to the apoptotic Bcl-xS to induce tumor cell death. Since the delivery system can also deliver a plasmid DNA along with siRNA, different anti-cancer genes can be used in a combination therapy with siRNA. In aim 3, we will employ another nanoparticle formulation, i.e., LPH, which contains heparin sulfate to deliver doxorubicin (dox), a potent anti-cancer drug, either by itself or together with EGFR siRNA. Since dox and EGFR silencing induce apoptosis by different mechanisms, we expect at least an additive, if not synergistic, effect. Dox will be chemically conjugated to heparin sulfate and co-formulated in LPH. The goal of the project is to develop efficient anti-tumor nanoparticle agents for cancer therapy. PUBLIC HEALTH RELEVANCE: The goal of the project is to develop a tumor specific, systemic delivery system for siRNA for cancer therapy. A self-assembled nanoparticle formulation will be used as a delivery vehicle. The project uses lung cancer and lung metastasis in mice as the disease model.