In the recent years, we have successfully modified the Liposome/Protamine/DNA (LPD) nanoparticle formulation for targeted delivery of siRNA to the human lung cancer cells in a xenograft model. This core/shell, self-assembled nanoparticles contained a compact protamine/DNA/siRNA core which is wrapped around by two cationic lipid bilayers. When the nanoparticles were incubated with a polyethylene glycol (PEG)-phospholipid conjugate (DSPE-PEG), the outer bilayer was stripped off, but the inner bilayer survived with a high degree of PEGylation. The densely packed surface PEG formed a brush protection layer to shield the cationic charges of the nanoparticles and reduced opsonization by serum proteins. The result was a very low degree of uptake by the liver and the spleen, and a very high level of tumor uptake, up to 60-80% injected dose per g tissue. If a targeting ligand, anisamide, was tethered to the distal end of PEG, the targeted nanoparticles efficiently delivered siRNA to silence a target gene in the entire tumor. However, upon a closer look at the delivered siRNA, most of the dose was sequestered in the endosomes and was not bioavailable. This is because the formulation did not possess any endosomal lytic activity. Thus, we propose to replace the core of LPD with Ca phosphate (CaP) which dissolves at the acidic endosome pH. We expect that dissolved CaP will significantly increase the osmotic pressure of the endosome and induce swelling and rupture of the organelle, resulting in the release of the encapsulated siRNA. The proposed improvement of the non-viral vector will combine high level of tumor uptake and efficient endosome release of the siRNA cargo. The other aim of the project will deal with tumors with not-so-leaky neovasculature. We have successfully prepared small bioactive lipoplex (SBL) by mixing siRNA and a cationic lipid, DOTAP, in a fluorohydrocarbon solvent at an elevated temperature and pressure. The resulting nanoparticles were small (30-50 nm), and active in transfection. We will further modify the surface of SBL with PEGylation and ligand tethering. We expect that the new nanoparticle will deliver siRNA to tumor cells in which the neovasculature is not so leaky.

Public Health Relevance

The project will address two pressing issues in delivering siRNA to the tumor. The first is to improve the release of siRNA from the endosome to the cytoplasm. The other is to transport siRNA to tumors with not-so-leaky vasculature. If successful, the project will significantly advance siRNA as cancer therapeutics.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA149363-02
Application #
8053486
Study Section
Gene and Drug Delivery Systems Study Section (GDD)
Program Officer
Fu, Yali
Project Start
2010-04-01
Project End
2015-01-31
Budget Start
2011-02-01
Budget End
2012-01-31
Support Year
2
Fiscal Year
2011
Total Cost
$238,594
Indirect Cost
Name
University of North Carolina Chapel Hill
Department
Pharmacology
Type
Schools of Pharmacy
DUNS #
608195277
City
Chapel Hill
State
NC
Country
United States
Zip Code
27599
Liu, Lina; Wang, Yuhua; Miao, Lei et al. (2018) Combination Immunotherapy of MUC1 mRNA Nano-vaccine and CTLA-4 Blockade Effectively Inhibits Growth of Triple Negative Breast Cancer. Mol Ther 26:45-55
Wang, Yuhua; Zhang, Lu; Xu, Zhenghong et al. (2018) mRNA Vaccine with Antigen-Specific Checkpoint Blockade Induces an Enhanced Immune Response against Established Melanoma. Mol Ther 26:420-434
Huo, Meirong; Zhao, Yan; Satterlee, Andrew Benson et al. (2017) Tumor-targeted delivery of sunitinib base enhances vaccine therapy for advanced melanoma by remodeling the tumor microenvironment. J Control Release 245:81-94
Cheng, Lifang; Wang, Yuhua; Huang, Leaf (2017) Exosomes from M1-Polarized Macrophages Potentiate the Cancer Vaccine by Creating a Pro-inflammatory Microenvironment in the Lymph Node. Mol Ther 25:1665-1675
Miao, Lei; Guo, Shutao; Lin, C Michael et al. (2017) Nanoformulations for combination or cascade anticancer therapy. Adv Drug Deliv Rev 115:3-22
Shi, Kai; Zhao, Yi; Miao, Lei et al. (2017) Dual Functional LipoMET Mediates Envelope-type Nanoparticles to Combinational Oncogene Silencing and Tumor Growth Inhibition. Mol Ther 25:1567-1579
Satterlee, Andrew B; Attayek, Peter; Midkiff, Bentley et al. (2017) A dosimetric model for the heterogeneous delivery of radioactive nanoparticles In vivo: a feasibility study. Radiat Oncol 12:54
Miao, Lei; Liu, Qi; Lin, C Michael et al. (2017) Targeting Tumor-Associated Fibroblasts for Therapeutic Delivery in Desmoplastic Tumors. Cancer Res 77:719-731
Hu, Kaili; Miao, Lei; Goodwin, Tyler J et al. (2017) Quercetin Remodels the Tumor Microenvironment To Improve the Permeation, Retention, and Antitumor Effects of Nanoparticles. ACS Nano 11:4916-4925
Xiong, Yang; Zhao, Yi; Miao, Lei et al. (2016) Co-delivery of polymeric metformin and cisplatin by self-assembled core-membrane nanoparticles to treat non-small cell lung cancer. J Control Release 244:63-73

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