LPD Nanoparticles in Anti-Cancer Therapy

描述(申请人提供)：我们最近开发了一种名为LPD的苯甲酰胺靶向纳米颗粒制剂，用于在裸鼠模型中将siRNA静脉注射到表达sigma受体的人肺癌细胞NCI-H460中。SiRNA被设计用来沉默表皮生长因子受体(EGFR)。由于肿瘤的高度摄取(每克组织注射剂量的70%-80%)，EGFR在整个肿瘤中完全沉默。尽管高效地传递siRNA和沉默目的癌基因，但体内肿瘤细胞仅表现出部分(~15%)的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，我们将封装针对不同细胞癌基因的多组siRNA，以显示至少一个相加的，如果不是协同的，在肿瘤杀伤中的作用。Let-7miRNA还将在该模型中测试其肿瘤抑制活性。化学修饰的siRNA，包括那些含有硼磷酸盐的siRNA，也将进行长时间沉默效果的测试。我们发现，阳离子脂质DOTAP是LPD配方中的主要成分，具有抗凋亡活性，可以保护肿瘤细胞免于死亡。我们发现了另一种阳离子脂质，它本身就可以杀死肿瘤细胞，可以用来取代siRNA配方中的DOTAP。初步数据表明，以苯甲酰胺为靶点的LPD也能将siRNA传递到小鼠黑色素瘤B16F10细胞的肺转移中。在目标2中，我们将传递不同的siRNA来诱导小鼠黑色素瘤细胞的凋亡。我们还将测试一种剪接转移寡核苷酸，它将把抗凋亡的Bcl-xL转化为凋亡的Bcl-xs，以诱导肿瘤细胞死亡。由于递送系统还可以将质粒DNA与siRNA一起递送，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，我们将使用另一种纳米制剂，即LPH，它包含硫酸肝素，以单独或与EGFR siRNA一起传递有效的抗癌药物阿霉素(DOX)。由于DOX和EGFR沉默通过不同的机制诱导细胞凋亡，我们预计至少是相加的，如果不是协同作用的话。DOX将与硫酸肝素化学偶联，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制剂。公共卫生相关性：该项目的目标是开发一种肿瘤特异性的系统性siRNA递送系统，用于癌症治疗。一种自组装纳米颗粒配方将被用作运载工具。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.