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Laboratory of Drug Targeting

Sm_ninjaWe have been working on liposomes and lipidic nanoparticles for drug/gene delivery. Current activities are focused in the development of non-viral vectors for pDNA/siRNA therapy and receptor-mediated drug targeting.

 

Research Projects

To enhance de-assembly of nanoparticle in acidic endosomes, the core of the nanoparticle has been replaced with calcium phosphate nano-precipitates. The resulting nanoparticles, referred to as LCP, are about forty-fold more effective in delivering siRNA than LPD nanoparticles.
The newest version, LCP-II, is small (about 30-35 nm) and contains a hollow calcium phosphate core.

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Publications

  • Li, J., Yang, Y. and Huang, L. Calcium Phosphate Nanoparticles with an Asymmetric Lipid Bilayer Coating for siRNA Delivery to The Tumor. J. Controlled Release 158: 108-114, 2012.
  • Yang, Y., Li, J., Liu, F. and Huang, L. Systemic Delivery of siRNA via LCP Nanoparticle Efficiently Inhibits Lung Metastasis. Molecular Therapy, 20:609-615, 2012.
  • Satterlee, A.B., Yuan, H. and Huang, L. A Radio-Theranostic Nanoparticle with High Specific Drug Loading for Cancer Therapy and Imaging. Journal of Controlled Release, 217:170-182, 2015.

We have developed novel lipid bilayer enclosed nano-precipitate of cisplatin with greater than 80 percent drug loading. The nanoparticles efficiently deliver large amounts of cisplatin to tumor cells in vivo and showed a significant bystander effect. Cisplatin diffuses from the cells taken up the nanoparticles and kills the neighboring cells. Cisplatin NPs and Gemcitabine NPs can be co-encapsulated in the same PLGA NPs for precise ratio-metric delivery of two drugs for treating bladder cancer.

 

 

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Publications

  • Guo, S. T., Wang, Y. H., Miao, L., Xu, Z. H., Lin, C. M., Zhang, Y. and Huang, L. Lipid-Coated Cisplatin Nanoparticles Induce Neighboring Effect and Exhibit Enhanced Anticancer Efficacy. ACS Nano, 7: 9896-9904, 2013.
  • Guo, S. T., Miao, L., Wang, Y.H. and Huang, L. Unmodified Drug Used as a Material to Construct Nanoparticles: Delivery of Cisplatin for Enhanced Anti-Cancer Therapy. J. Controlled Release, 174:137-142, 2014.
  • Miao, L., Guo, S.T., Zhang, J., Kim, W.Y. and Huang, L. Nanoparticles with Precise Ratiometric Co-Loading and Co-Delivery of Gemcitabine Monophosphate and Cisplatin for Treatment of Bladder Cancer. Advanced Functional Materials, 24(42):6601-6611, 2014.

The tumor microenvironment (TME) serves as a multidrug resistant center for tumors under the assault of chemotherapy and a physiological barrier against the penetration of therapeutic nanoparticles (NP). Tumor associated fibroblasts (TAFs), the major cellular component of TME, are recruited by tumor cells to build the TME, which separates tumor vessels and tumor cells. We have originally discovered that combined NP containing gemcitabine and cisplatin efficiently kill TAFs and down-regulate TME, resulting in excellent inhibition of tumor growth.

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However, a drug resistant phenotype gradually arises after repeated doses of chemotherapeutic NP. In a later study, the acquisition of drug resistant phenotypes in the TME after repeated cisplatin NP treatment was examined. Particularly, this study was aimed at investigating the effects of NP damaged TAFs on neighboring cells and alteration of stromal structure after cisplatin treatment. Findings suggested that while off-targeted NP damaged TAFs and inhibited tumor growth after an initial dose, chronic exposure to cisplatin NP led to elevated secretion of Wnt16 in a paracrine manner in TAFs. Wnt16 upregulation was then attributed to heightened tumor cell resistance and stroma reconstruction. Results attest to the efficacy of Wnt16 knockdown using a nanoparticle delivered siRNA against Wnt16 in damaged TAFs as a promising combinatory strategy to improve efficacy of cisplatin NP in a stroma-rich bladder cancer model.

 

Publications

  • Zhang, J., Miao, L., Guo, S. T., Zhang, Y., Zhang, L., Satterlee, A., Kim, W. Y., and Huang, L. Synergistic anti-tumor effects of combined gemcitabine and cisplatin nanoparticles in a stroma-rich bladder carcinoma model. J. Controlled Release, 182:90-96, 2014.
  • Miao, L., Wang, Y., Lin, C., Xiong, Y., Chen, N., Zhang, Lu., Kim, W., and Huang, L. Nanoparticle modulation of the tumor microenvironment enhances therapeutic efficacy of cisplatin. J. Controlled Release, 217:27-41, 2015.

Using the LCP nanoparticles, we have developed a novel cancer vaccine by encapsulating a peptide of a tumor associated antigen or its mRNA. Subcutaneous administration of the vaccine nanoparticles delivers the antigen to the dendritic cells in the draining lymph nodes and stimulates a strong cytotoxic T-lymphocyte response, leading to inhibition of tumor growth. Vaccine activity can be further enhanced by delivering siRNA against key cytokines, such as TGF-β, that control the suppressive tumor microenvironment. We are currently investigating siRNA, miRNA and/or small molecule drugs that can inhibit the myelo-derived suppressive cells and Treg cells to further enhance the vaccine activity. For example, sunitinib base encapsulated in PLGA NPs can normalize the tumor vasculature and greatly enhance the penetration of polymeric micelles.

Publications

  • Xu, Z.H., Ramishetti S., Tseng, Y.-C., Guo S. T., Wang Y.H., and Huang, L. Multifunctional nanoparticles co-delivering Trp2 peptide and CpG adjuvant induce potent cytotoxic T-lymphocyte response against melanoma and its lung metastasis. J. Controlled Release. 172:259-265, 2013.
  • Xu, Z.H., Wang, Y.H., Zhang, L. and Huang, L. Nanoparticle-Delivered TGF-β siRNA Enhances Vaccination against Advanced Melanoma by Modifying Tumor Microenvironment. ACS Nano, 8(4):3636-3645, 2014.
  • Zhao, Y. Huo, M., Xu, Z. Wang, Y. and Huang, L. Nanoparticle Delivery of CDDO-Me Remodels the Tumor Microenvironment and Enhances Vaccine Therapy for Melanoma. Biomaterials, 68:54-66, 2015.
  • Liu, Q., Zhu, H. Liu, Y., Musetti, S. and Huang, L. BRAF peptide vaccine facilitates therapy of murine BRAF-mutant melanoma. Cancer Immunology, Immunotherapy, 2017 Nov 1. doi: 10.1007/s00262-017-2079-7.

Huang6.1LCP-II nanoparticles targeted with galactose have been prepared to deliver plasmid DNA to hepatocytes in the liver. Approximately 50 percent of the IV injected nanoparticles accumulate in the liver hepatocytes, with virtually no accumulation in the Kupffer cells.

Through the use of a cationic peptide plasmid DNA is condensed and the delivered DNA was imported to the nuclei of the hepatocytes. Consequently, high levels of transgene expression in the liver were observed. This nonhydrodynamic method of in vivo gene transfer shows a high potential for liver gene therapy.

Publications

  • Hu, Y. X., Haynes, M.T., Wang, Y. H., Liu, F. and Huang, L. A Highly Efficient Synthetic Vector: Non-Hydrodynamic Delivery of DNA to Hepatocyte Nuclei In Vivo. ACS Nano. 7:5376-5384, 2013.
  • Liu, Y., Hu, Y. X. and Huang, L. Influence of Polyethylene Glycol Density and Surface Lipid on Pharmacokinetics and Biodistribution of LCP Nanoparticles. Biomaterials, 35:3027-3034, 2014.
  • Goodwin, T.J., Zhou, Y., Musetti, S.N., Liu, R. and Huang, L. Local and Transient Gene Expression Primes the Liver to Resist Cancer Metastasis. Science Translational Medicine, 8(364):364ra153, 2016.
  • Goodwin, T.J., Shen, L., Hu, M., Li, J., Feng, R., Dorosheva, O. Liu, R. and Huang, L. Liver Specific Gene Immunotherapies Resolve Immune Suppressive Ectopic Lymphoid Structures of liver metastases and prolong survival. Biomaterials, 141:260-271, 2017.

Using LCP nanoparticles, we are able to condense and encapsulate mRNA vaccines, disrupt endosomes for mRNA release, and potentiate dendritic cell maturation for potent immune response. The simultaneous LCP delivery of mRNA vaccine and siRNA against PD-L1 to DCs would further remove the negative regulator during the T cell priming process, lead to increased T cell activation and proliferation.
Publications
  • Wang, Y., Zhang, L., Xu, Z., Miao, L. and Huang, L. mRNA Vaccine with Antigen-Specific Check Point Blockade Induces an Enhanced Immune Response Against Established Melanoma. Molecular Therapy, in press, 2017.
  • Liu, L., Wang, Y., Miao, L., Liu, Q., Musetti, S., Li., J. and Huang, L. Combination Immunotherapy of MUC1 mRNA Nano-vaccine and CTLA-4 Blockade Effectively Inhibits Growth of Triple Negative Breast Cancer. Molecular Therapy, 2018 Jan 3;26(1):45-55. doi: 10.1016/j.ymthe.2017.10.020.

 

 

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Metformin a widely implemented anti-diabetic regimen exhibits potent anticancer efficacies. Herein, a polymeric construction of Metformin, PolyMetformin (PolyMet) has been successfully synthesized through conjugation of linear polyethylenimine (PEI) with dicyandiamide. The delocalization of cationic charges in the biguanide groups of PolyMet reduces the toxicity of PEI both in vitro and in vivo. Furthermore, the polycationic properties of PolyMet permits capture of siRNA into a core-membrane structured Lipid-Polycation-Hyaluronic acid (LPH) nanoparticle for systemic gene delivery. Advances herein permit LPH-PolyMet nanoparticles to facilitate siRNA delivery for gene knockdown in xenografts, leading to enhanced tumor suppressive efficacy. Even in the absence of RNAi, LPH-PolyMet nanoparticles acts similarly to Metformin and induces antitumor efficacy through activation of the AMPK and inhibition of the mTOR. In essence, LPH-PolyMet successfully combines the intrinsic anticancer efficacy of Metformin with the tumor suppressive effects of siRNA to enhance therapeutic index of an anticancer gene therapy.

Publications
  • Zhao, Y., Wang, W., Guo, S., Wang, Y., Miao, L, Xiong, Y. and Huang, L., PolyMetformin Polymer Combines Carrier and Anti-Cancer Activities for in vivo siRNA delivery. Nature Communications, 7:11822, 2016.
  • Xiong, Y., Zhao, Y., Miao, L., Lin, C.M. and Huang, L. Co-Delivery of Polymeric Metformin and Cisplatin by Self-Assembled Core-Membrane Nanoparticles to Treat Non-Small Cell Lung Cancer. Journal of Controlled Release, 244: 63–73, 2016.

In collaboration with professor Rihe Liu, who has designed fusion proteins with high affinity binding to a chemo/cytokine or a receptor, we have used either LPD or LCP NPs to deliver plasmid DNA encoding a trap to the tumor or liver to relieve the suppressive immune microenvironment. The approach, with or without combination with a chemo drug or siRNA, often results in significant tumor growth inhibition. We have used several different traps against CXCL12, PD-L1, Wnt5a, IL-6 and IL-10 in orthotopic tumor models of breast, colon, pancreas and melanoma.
Publications
  • Goodwin, T.J., Zhou, Y., Musetti, S.N., Liu, R. and Huang, L. Local and Transient Gene Expression Primes the Liver to Resist Cancer Metastasis. Science Translational Medicine, 8(364):364ra153, 2016.
  • Miao, L., Li, J., Liu, Q., Feng, R., Das, M., Lin, C., Goodwin, T., Dorosheva, O., Liu, R., Huang, L. Transient and Local Expression of Chemokine and Immune Checkpoint Traps to Treat Pancreatic Cancer. ACS Nano, 11: 8690–8706, 2017.
  • Liu, Q., Zhu, H., Tiruthani, K., Shen, L., Chen, F., Gao, K., Zhang, X., Hou, L., Wang, D., Liu, R. and Huang, L. Nanoparticle-Mediated Trapping of Wnt Family Member 5A in Tumor Microenvironments Enhances Immunotherapy for B-Raf Proto-Oncogene-Mutant Melanoma. ACS Nano, 2018 Jan 25. doi: 10.1021/acsnano.7b07384

Desmoplastic tumors contain many tumor associated fibroblasts which are located near the microvessels. We have discovered that TAFs over-express sigma receptors such that NPs targeted with aminoethylanisamide are taken up by TAFs much more so than the tumor cells. This is a binding site barrier for NP delivery of drugs and genes to the tumor cells. We have turned the drawback of the off-target effect to a new strategy for cancer therapy by deliberately delivering drugs and genes to TAFs.
Publications
  • Miao, L., Newby, J., Lin, C., Zhang, L., Xu, F., Kim, W.Y., Forest, M.G., Lai, S.K., Milowsky, M.I., Wobker, S.E. and Huang, L. The Binding Site Barrier Elicited by Tumor Associated Fibroblasts Interferes Disposition of Nanoparticles in Stroma-Vessel Type Tumors. ACS Nano, 10:9243-9258, 2016.
  • Miao, L., Liu, Q., Lin, C.M., Luo, C., Wang, Y., Liu, L., Yin, W., Hu, S., Kim, W.Y. and Huang, L. Targeting Tumor-associated Fibroblasts for Therapeutic Delivery in Desmoplastic Tumors. Cancer Research, 77(3); 719–731, 2017.
  • Hu, K., Miao, L., Goodwin, T.J, Li, J., Liu, Q. and Huang, L. Quercetin Remodels the Tumor Microenvironment to Improve the Permeation, Retention, and Antitumor Effects of Nanoparticles. ACS Nano, 11(5):4916-4925, 2017.

Leaf Huang, PhD

  • Birthdate: September 23, 1946
  • Birthplace: China
  • Citizenship: Naturalized citizen of the United States
  • Phone: 919-843-0736
  • Fax: 919-966-0197
  • E-mail: leafh@unc.edu

Address
UNC Eshelman School of Pharmacy
University of North Carolina at Chapel Hill
CB# 7360
Chapel Hill, NC 27599

Click here for a list of publications

Education

Degree Year University Major
BS 1968 National Taiwan University, Taipei Physics
PhD 1974 Michigan State University, East Lansing, MI Biophysics
Postdoctoral Fellowship 1974-1976 Carnegie Institute of Washington, Baltimore, MD

I was born into a college professor’s family in Taiwan. My father was a professor of horticulture for many years. When I was a teenager, I started working in his lab measuring sugar and protein content of Lichee fruit (it was delicious!).

My official science career started when I was a physics major at the National Taiwan University. In my junior year, I became immensely interested in biology. My professor, however, would not allow me to change to a biology major. I suffered through my senior year and decided to pursue my graduate study in biology, after the completion of a year of military service.

No US graduate program in biology would accept me because of my poor background in biology and chemistry. Only the biophysics program at Michigan State University had enough mercy and courage to take me as a graduate student. I still remember having to learn the difference between a microtubule and a microfilament in a freshman biology class. (I was the only graduate student in the class).

My first lab experience was with Professor Barney Rosenberg who had just discovered cis-platinum as a potent anticancer drug. I really did not have enough wisdom and intelligence to appreciate the work and I chose to work with another professor who played with electron spin resonance. Somehow, those electrons jumping between two giant magnets were much more friendly to me than those mice running around the cage.

I finished my Ph.D. in 1974 and took a postdoc position in Dr. Richard Pagano’s lab at Carnegie Institute of Washington. It took me and my newly-wed wife, Shilling, some time to get used to the life in a big city, i.e. Baltimore. Richard taught me the art and science of liposomes, which became my first love in science.

I went down to Knoxville, TN in 1976 to take on a position as an assistant professor of biochemistry at the University of Tennessee. As soon as we arrived, Shilling and I got lost in Knoxville and decided to ask for directions in a local gas station. A very nice man spent five minutes trying to tell me where the University was, but I could not understand him because of his heavy southern accent. I remember telling my wife, “Let us stay for a couple of years and then move back to the north.”

Well, that couple of years turned into fifteen. We fell in love with the city (picked up our own southern accents!). Our children grew up in Knoxville, and were very reluctant to leave when we decided to move to Pittsburgh in 1991.

We liked Pittsburgh a lot except for the occasional harsh winters. Shilling and I finally became used to our empty nest, as both of our children have left home for college. I liked my job at Pitt, which gave me a chance to direct a new Center for Pharmacogenetics. I also hoped that Professor Rosenberg would not notice the fact that I have started working with cis-platinum.

Well, the time came again for another move; this time, going back to the South. Our lab (the Laboratory of Drug Targeting) moved with me to the University of North Carolina at Chapel Hill in July of 2005. I am now an Eshelman Distinguished Professor at the UNC Eshelman School of Pharmacy.

God Bless You!!

Leaf Huang

2017-2020 Shanghai University of Traditional Chinese Medicine Adjunct Professor
2016-2017 Shenyang Pharmaceutical University, China Visiting Professor
2013-2016 Fudan University, China Advanced Visiting Scholar
2012 Fourth Military Medical University, China Visiting Professor
2012-present Division of Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC Fred Eshelman Distinguished Professor (with tenure)
2010-2017 Chung-Yuan Christian University, Taiwan Visiting Chair Professor
2010-present UNC-NCSU Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC Professor (joint appointment)
2005-2012, 2015-present Division of Molecular Pharmaceutics, Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC Fred Eshelman Distinguished Professor (with tenure) and Chair

Lipogen, Inc. Knoxville, TN 1987-1990
Rx Therapeutics, Inc. Woodland, TX 1992-1996
Lipella, Inc. Pittsburgh, PA 2005-present
PDS Biotechnology, Inc. Princeton, NJ 2006-present
Qualiber, Inc Chapel Hill, NC 2010-2017
KRB, Inc. Taiwan 2013-2014
OncoTrap Chapel Hill, NC 2016-present

Total Direct Cost per year Years Inclusive Grant Number and Title Source
$217,500 2013-2018 “Hepatic non-viral gene therapy” 1 R01 DK100664, PI: L. Huang NIH
$1,494,990 2015-2020 “Nano Approaches to Modulate Host Cell Response for Cancer Therapy” 1U54CA198999-01, Co-leader: L. Huang & J.E. Tepper, Project 1, PI: L. Huang. $302,668 NIH
$630,000 2015-2017 “Priming the Liver to Resist Metastasis of Colorectal Cancer” Eshelman Institute

leaf_huang_lab

 

Recent Graduate Students, Post-Doctoral Fellows and Visiting Scholars Supervised and Their Current/Last Known Positions (since 2010):

Graduate Students

Yunching “Becky” Chen Nanoparticle delivery of siRNA for cancer therapy (Ph.D. 2010), Associate Professor, National Tsing Hua University, Taiwan
Jiexin (Jason) Deng Understanding paclitaxel /pluronic F127 nanocrystals prepared by the stabilization of nanocrystal (SNC) method. (MS, 2009), Graduate Student, University of Florida
Elisabeth Vasievich Lipid-Based Cancer Vaccines. (Ph.D. 2011), Manager, Roche/Genentech
Yang Liu Pharmacokinetics and Biodistribution of LCP Nanoparticles. (Ph.D. 2012), Assistant Professor, School of Pharmacy, Chapman University
Yu-Cheng Tseng LCP Nanoparticles for Tumor and lymph Node Metastasis Imaging. (Ph.D. 2013), Senior Scientist, Taiwan Liposome Company, Taipei, Taiwan
Yuan Zhang Systemic Delivery of Phosphorylated Nucleoside Analogues and siRNA via LCP Nanoparticles for Cancer Therapy. (Ph.D. 2013) Assistant Professor, School of Pharmacy, University of Rhode Island
Andrew Satterlee Applications for a Radio-Theranostic Nanoparticle with High Specific Drug Loading (Ph.D. 2016) Postdoc, University of North Carolina at Chapel Hill
Lei Miao The Role of Tumor Desmoplasia in Nanoparticle Delivery of Drugs and Genes (Ph.D. 2016) Postdoc, Massachusetts Institute of Technology
Matthew Haynes Maximizing the Supported Bilayer Phenomenon: Liposomes Comprised Exclusively of PEGylated Phospholipid for Enhanced Local and Systemic Delivery (Ph.D. 2017) Consultant
Tyler Goodwin Treatment of Liver Metastasis via Nanoparticle Delivery of Engineered Gene Immunotherapies Expressed Locally and Transiently by the Liver Hepatocytes (Ph.D. 2017) Senior Scientist, Precision Biosciences, Durham, NC
Qi Liu (Ph.D. 2018 expected)
Sara Musetti (Ph.D. 2019 expected)
Manisit Das (Ph.D. 2019 expected)
Mengying Hu (Ph.D. 2020 expected)
Yun Liu (Ph.D. 2020 expected)

Postdoctoral Fellows

Srinivas Ramishetti (2009 – 2013) Scientist, Tel Aviv University, Israel
Yunxia Hu (2010-2012) Senior Investigator, Chinese Academy of Sciences, Yantai, China
Yuhua (Al) Wang (2010-2015) Director of Research, OncoTrap, Inc. Chapel Hill, NC
Shutao Guo (2011-2014) Professor, Nankai University, Tianjin, China
Zhenghong Xu (2011-2014) Scientist, LEAF Pharmaceuticals Inc., Cambridge, MA
Yi Zhao (2013-2016) Scientist I, Takara Bio USA, Mountain View, CA
Wantong Song (2016-present)
Sai An (2016-present)
Limei Shen (2016-present)
Nasha Qiu (2017-present)

Visiting Scholars (since 2015)

Cong Luo (2015-2016) PhD student, Shenyang Pharmaceutical University, Shenyang, China
Kai Shi (2015-2016) Associated Professor, Shenyang Pharmaceutical University, Shenyang, China
Kaili (Kelly) Hu (2015-2016) Professor, Shanghai Traditional Chinese Medical University, Shanghai, China
Jing Qin (2015-2016) Associate Professor, Fudan University, Shanghai, China
Ying Xu (2015-2016) Associate Professor, Jiangsu University, Zhenjiang, China
Hongda Zhu (2016-2017) Associate Professor, Hubei University of Technology, Wuhan, China
Xiao Xie (2016-2017) Attending Surgeon, Xinhua Hospital, Shanghai, China
Xueqiong Zhang (2016-2017) Associate Professor, Wuhan University of Technology, Wuhan, China
Li Jing (2016-2016) Volunteer scientist
Haiyang Hu (2016-2017) Associate Professor, Shenyang Pharmaceutical University, Shenyang, China
Yanzhi Wang (2016-2017) Associate Professor, Zhengzhou University, Zhengzhou, China
Xiangnan Liu (2016-2017) Graduate student, Fudan University, Shanghai, China
Lin Hou (2017-2018) Associate Professor, Zhengzhou University, Zhengzhou, China
Lucia Salvioni (2017-2017) Graduate student, University of Milan, Italy
Ying Wang (2017-2017) Graduate student, Shenyang Pharmaceutical University, Shenyang, China
Ligeng Xu (2017-2018) Associate Professor, Suzhou University, Suzhou, China
Jing Zhang (2017-2018)

Associate Professor, Jiangxi University of Traditional Chinese Medicine

Nanchang, China
Yang Xiong (2017-2018) Professor, Zhejiang University of Traditional Chinese Medicine, Hangzhou, China
Huan Xu (2017-2018) Associate Professor, Liaoning Normal University, Dalian, China

Structure of DNA/lipid complex

Structure of DNA/lipid complex

Thin-section electron micograph of AuSCL. Multilamellar liposomes with multi-AuSC can be seen in this preparation (bar: 0.5 micrometers).

First published in: Gao, K. and Huang, L. Solid core liposomes with encapsulated colloidal gold particles. Biochim. Biophys. Acta 897:377-383, 1987.

Thin-section electron micograph of AuSCL. Multilamellar liposomes with multi-AuSC can be seen in this preparation (bar: 0.5 micrometers).

Freeze-fracture image of chylomicron fragment

Thanks to Simon Watkins, PhD, and the Center for Biological Imaging at the University of Pittsburgh for photo preparation and production.

Freeze-fracture image of chylomicron fragment

Smileosome

Smileosome

Smiling Liposome and Cute PLGA Nanoparticles

Smiling Liposome and Cute PLGA Nanoparticles

Kicking Nanos

Kicking Nanos

ImmunoTrap