Gene Medicine : A New Field of Molecular Medicine

Kim, Chong-Kook,Haider, Kh-H,Lim, Soo-Jeong The Pharmaceutical Society of Korea 2001 Archives of Pharmacal Research Vol.24 No.1

Gene therapy has emerged as a new concept of therapeutic strategies to treat diseases which do not respond to the conventional therapies. The principle of gene therapy is to Introduce genetic materials into patient cells to produce therapeutic proteins in these cells. Gene therapy is now at the stage where a number of clinical trials have been carried out to patients with gene-deficiency disease or cancer. Genetic materials for gene therapy are generally composed of gene expression system and gene delivery system. For the clinical application of gene therapy in a way which conventional drugs are used, researches have been focused on the design of gene delivery system which can offer high transfection efficiency with minimal toxicity. Currently, viral delivery systems generally provide higher transfection efficiency compared with non-viral delivery systems while non-viral delivery systems are less toxic, less immunogenic and manufacturable in large scale compared with viral systems. Recently, novel strategies towards the design of new non-viral delivery system, combination of viral and non-viral delivery systems and targeted delivery system have been extensively studied. The continued effort in this area will lead us to develop gene medicine as "gene as a drug" in the near future.

Recent advances in polymeric drug delivery systems

Yong Kiel Sung,Sung Wan Kim 한국생체재료학회 2020 생체재료학회지 Vol.24 No.2

Background: Polymeric drug delivery systems have been achieved great development in the last two decades. Polymeric drug delivery has defined as a formulation or a device that enables the introduction of a therapeutic substance into the body. Biodegradable and bio-reducible polymers make the magic possible choice for lot of new drug delivery systems. The future prospects of the research for practical applications has required for the development in the field. Main body: Natural polymers such as arginine, chitosan, dextrin, polysaccharides, poly (glycolic acid), poly (lactic acid), and hyaluronic acid have been treated for polymeric drug delivery systems. Synthetic polymers such as poly (2-hydroxyethyl methacrylate), poly(N-isopropyl acrylamide)s, poly(ethylenimine)s, dendritic polymers, biodegradable and bio-absorbable polymers have been also discussed for polymeric drug delivery. Targeting polymeric drug delivery, biomimetic and bio-related polymeric systems, and drug-free macromolecular therapeutics have also treated for polymeric drug delivery. In polymeric gene delivery systems, virial vectors and non-virial vectors for gene delivery have briefly analyzed. The systems of non-virial vectors for gene delivery are polyethylenimine derivatives, polyethylenimine copolymers, and polyethylenimine conjugated bio-reducible polymers, and the systems of virial vectors are DNA conjugates and RNA conjugates for gene delivery. Conclusion: The development of polymeric drug delivery systems that have based on natural and synthetic polymers are rapidly emerging to pharmaceutical fields. The fruitful progresses have made in the application of biocompatible and bio-related copolymers and dendrimers to cancer treatment, including their use as delivery systems for potent anticancer drugs. Combining perspectives from the synthetic and biological fields will provide a new paradigm for the design of polymeric drug and gene delivery systems.

Molecular Recognition Enables Nanosubstrate-Mediated Delivery of Gene-Encapsulated Nanoparticles with High Efficiency

Peng, Jinliang,Garcia, Mitch André,Choi, Jin-sil,Zhao, Libo,Chen, Kuan-Ju,Bernstein, James R.,Peyda, Parham,Hsiao, Yu-Sheng,Liu, Katherine W.,Lin, Wei-Yu,Pyle, April D.,Wang, Hao,Hou, Shuang,Tse American Chemical Society 2014 ACS NANO Vol.8 No.5

<P/><P>Substrate-mediated gene delivery is a promising method due to its unique ability to preconcentrate exogenous genes onto designated substrates. However, many challenges remain to enable continuous and multiround delivery of the gene using the same substrates without depositing payloads and immobilizing cells in each round of delivery. Herein we introduce a gene delivery system, nanosubstrate-mediated delivery (NSMD) platform, based on two functional components with nanoscale features, including (1) DNA⊂SNPs, supramolecular nanoparticle (SNP) vectors for gene encapsulation, and (2) Ad-SiNWS, adamantane (Ad)-grafted silicon nanowire substrates. The multivalent molecular recognition between the Ad motifs on Ad-SiNWS and the β-cyclodextrin (CD) motifs on DNA⊂SNPs leads to dynamic assembly and local enrichment of DNA⊂SNPs from the surrounding medium onto Ad-SiNWS. Subsequently, once cells settled on the substrate, DNA⊂SNPs enriched on Ad-SiNWS were introduced through the cell membranes by intimate contact with individual nanowires on Ad-SiNWS, resulting in a highly efficient delivery of exogenous genes. Most importantly, sequential delivery of multiple batches of exogenous genes on the same batch cells settled on Ad-SiNWS was realized by sequential additions of the corresponding DNA⊂SNPs with equivalent efficiency. Moreover, using the NSMD platform <I>in vivo</I>, cells recruited on subcutaneously transplanted Ad-SiNWS were also efficiently transfected with exogenous genes loaded into SNPs, validating the <I>in vivo</I> feasibility of this system. We believe that this nanosubstrate-mediated delivery platform will provide a superior system for <I>in vitro</I> and <I>in vivo</I> gene delivery and can be further used for the encapsulation and delivery of other biomolecules.</P>

암세포주에 양이온성 리피드 복합체를 이용한 유전자 전달의 효율성 비교

최종선,이석준,곽희진,홍승희 대한구강악안면병리학회 2011 대한구강악안면병리학회지 Vol.35 No.5

For investigate intracellular function and role of genes in the biological processes, various gene delivery methods into cell have been developed. Many studies performed to construct optimum conditions of gene delivery into cells and tissues. In this study, we examined efficiency of gene delivery-complexed with cationic lipid vector in human cancer cell lines. GFP plasmids were complexed with cationic lipid and transfected into human cancer cell lines at different concentrations. And then, expression of GFP was analysed with fluorescent microscope and FACS. To determine efficiency of gene delivery, we investigated GFP expression level in various cancer cell lines. GFP expression cells were not shown in hepatocellular carcinoma cell line HepG2 and lung carcimona cell line A549 after 24hr transfection, while, GFP expression cells were observed at 500ng concentration after 48hr transfection. In colorectal carcinoma cell line HCT116, GFP expression cells were observed at 100ng and 500ng concentrations after 24hr transfection and slightly increased at 48hr. After transfection into ovary adenocarcinoma cell line SKOV3, we could found that many cells expressed GFP at 500ng concentration after 24hr and highly elevated GFP expression cells after 48hr. For further evaluate gene expression level, we confirmed GFP expression level by using FACS analysis after 48hr transfection. As a result, HepG2 was expressed GFP in very low level at 10ng, 100ng, and 500ng concentrations. We also identified that GFP was expressed low level at 10ng and 100ng in HCT116 and A549, but highly increased at 500ng concentration to 14.19% and 16.57%, respectively. In case of SKOV3, GFP expression was highly elevated to 13.14% at 100ng and 58.10% at 500ng compared with 10ng transfection. By Comparing efficiency of gene expression among cancer cell lines, GFP expression was similar with cell lines at 10ng transfection, but significantly differed from cell lines at 500ng higher concentration. Additionally, GFP expression level of SKOV3 was showed about 10 fold higher than HepG2, and about 4 fold higher than HCT116 and A549 at 500ng. These results demonstrated that efficiency of gene delivery-complexed with cationic lipid vector was the highest in SKOV3, while HepG2 was showed the lowest efficiency. Taken together, we could determined that efficiency of gene delivery into cells differed from each human cancer cell lines. Our study suggest that cellular properties should be considered in gene delivery-complexed with cationic lipid vector to improve cellular expression efficiency of gene.

Molecular Imaging of Biological Gene Delivery Vehicles for Targeted Cancer Therapy: Beyond Viral Vectors

Min, Jung-Joon,Nguyen, Vu H.,Gambhir, Sanjiv S. The Korea Society of Nuclear Medicine 2010 핵의학 분자영상 Vol.44 No.1

Cancer persists as one of the most devastating diseases in the world. Problems including metastasis and tumor resistance to chemotherapy and radiotherapy have seriously limited the therapeutic effects of present clinical treatments. To overcome these limitations, cancer gene therapy has been developed over the last two decades for a broad spectrum of applications, from gene replacement and knockdown to vaccination, each with different requirements for gene delivery. So far, a number of genes and delivery vectors have been investigated, and significant progress has been made with several gene therapy modalities in clinical trials. Viral vectors and synthetic liposomes have emerged as the vehicles of choice for many applications. However, both have limitations and risks that restrict gene therapy applications, including the complexity of production, limited packaging capacity, and unfavorable immunological features. While continuing to improve these vectors, it is important to investigate other options, particularly nonviral biological agents such as bacteria, bacteriophages, and bacteria-like particles. Recently, many molecular imaging techniques for safe, repeated, and high-resolution in vivo imaging of gene expression have been employed to assess vector-mediated gene expression in living subjects. In this review, molecular imaging techniques for monitoring biological gene delivery vehicles are described, and the specific use of these methods at different steps is illustrated. Linking molecular imaging to gene therapy will eventually help to develop novel gene delivery vehicles for preclinical study and support the development of future human applications.

Utilizing carbon dots as non-viral vectors in gene delivery

박소연,한지은,나건 한국공업화학회 2020 한국공업화학회 연구논문 초록집 Vol.2020 No.-

Vectors are the most important component for gene therapy. The viral vectors are widely used because of their higher transfection efficiency. However, viral vectors have limitation of genetic material size, oncogenic potential and immunogenicity. Thus, the non-viral vectors have been developing to substitute viral vectors. In this study we utilized carbon dots (c-dots) as a non-viral vector and c-dots have unique properties such as great water solubility and low toxicity. The c-dots were generated using cationic polymer for gene delivery. The therapeutic gene complexed with c-dots (gene/c-dots) were transfected into human mesenchymal stem cells (hMSCs). C-dots have been found to be safer because c-dots are less toxic than cationic polymer. In addition, c-dots enable bioimaging after transfection of gene/c-dots into hMSCs (gene/c-dots@hMSCs). Even, the amount of secreted therapeutic protein from gene/c-dots@hMSCs was 25-fold higher than that from gene/cationic polymer@hMSCs.

Polyelectrolyte for in vivo sustained gene/drug delivery

이희형,장재형 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.1

Drug and gene delivery through intravascular injection spread throughout the body. So, Drug and gene delivery to target tissue locations is difficult. Therefore, direct injection into the target tissue is mostly for local delivery. However, without specific mediator, direct injection into the target tissue is difficult for sustained release because of the rate of diffusion of drugs and genes. Because of this, drug and gene delivery through mediators is essential. But an incision is necessary when the mediator is implanted through surgery. In order to minimize the incision site, injection should be possible. Therefore, this study was carried out by designing polyelectrolyte for the above-mentioned local & sustained drug and gene delivery. To produce the desired polyelectrolyte, we studied how to control the release rate of drugs and genes and reduce the immune response by controlling the combination of various materials applicable to the living body.

Modified mRNA as an alternative to plasmid DNA (pDNA) for transcript replacement and vaccination therapy

Youn, Hyewon,Chung, June-Key Informa Healthcare 2015 Expert opinion on biological therapy Vol.15 No.9

<P><B><I>Introduction:</I></B> Current gene therapy involves replacement of defective gene by delivery of healthy genetic material to precede normal function. Virus-mediated gene delivery is the most successful and efficient method for gene therapy, but it has been challenged due to serious safety concerns. Conversely, gene delivery using plasmid DNA (pDNA) is considered safer, but its transfection efficiency is much lower than virus-mediated gene transfer. Recently, mRNA has been suggested as an alternative option to avoid undesired insertion of delivered DNA sequences with higher transfection efficiency and stability.</P><P><B><I>Area covered: </I></B>In this review, we summarize the currently available strategies of mRNA modification to increase the therapeutic efficacy; we also highlight the recent improvements of mRNA delivery for <I>in vivo</I> applications of gene therapy.</P><P><B><I>Expert opinion:</I></B> The use of mRNA-based gene transfer could indeed be a promising new strategy for gene therapy. Notable advantages include no risk of integration into the genomic DNA, adjustable gene expression and easier modulation of the immune system. By reducing or utilizing the immunogenic properties, mRNA offers a promising tool for gene/or transcript replacement.</P>

Degradable poly(amido amine)s as gene delivery carriers

Arote, Rohidas B,Jiang, Hu-Lin,Kim, You-Kyoung,Cho, Myung-Haing,Choi, Yun-Jaie,Cho, Chong-Su Informa UK, Ltd. 2011 Expert opinion on drug delivery Vol.8 No.9

<P><B><I>Introduction:</I></B> In recent years, there has been a great deal of interest in the development of vectors which are being developed based on the capacity of polymers to mediate appropriate interactions with the cellular environment, or to interface with specific cellular processes. Several such vectors have been synthesized, resulting in biomacromolecules with low cytotoxicity and higher gene delivery ability.</P><P><B><I>Areas covered:</I></B> This review briefly describes the recent success of poly(amido amine)s (PAAs) as non-viral vectors, and highlights their promising future in the development of nucleic acid-based therapy. It also provides an overview on the synthesis, characterization and application of PAAs as gene carriers, which will be useful for various biological motifs. This review helps the readers to better understand the emergence of non-viral vectors for gene therapy, especially PAAs, their properties, their advantages and disadvantages and the gene therapy based on them.</P><P><B><I>Expert opinion:</I></B> The future of gene-based therapy needs to identify approaches to develop new carriers, depending on the properties of the biological membranes they face, and their physicochemical properties, in order to successfully deliver the genes to the target sites. With the emergence of a variety of non-viral vectors, such as biodegradable polymers, it may not take long before non-viral vectors are observed that are not just safe and tissue-specific, but even more efficient than viral vectors.</P>

Dexamethasone-loaded peptide micelles for delivery of the heme oxygenase-1 gene to ischemic brain

Lee, J.,Hyun, H.,Kim, J.,Ryu, J.H.,Kim, H.A.,Park, J.H.,Lee, M. Elsevier Science Publishers 2012 Journal of controlled release Vol.158 No.1

The R3V6 peptides, which are composed of a 3-arginine block and a 6-valine block, formed self-assembled micelles in aqueous solution. Dye quenching assays showed that a hydrophobic fluorescent dye, 5-dodecanoylaminofluorescein (DAF), interacted with and was loaded into the hydrophobic core of the micelles. In this study, dexamethasone-loaded R3V6 peptide micelles (R3V6-Dexa) were evaluated as a gene carrier. R3V6-Dexa had higher gene delivery efficiency in human embryonic kidney 293 cells compared to those of the R3V6 peptides and poly-l-lysine (PLL). Dexamethasone might stabilize the micelle structure of the R3V6 peptides by forming strong hydrophobic cores and enhanced the transfection efficiency. Furthermore, R3V6-Dexa reduced the expression of an inflammatory cytokine, interleukin-6 (IL-6), more efficiently in lipopolysaccharide (LPS)-induced Raw264.7 cells than did dexamethasone, suggesting that R3V6-Dexa is also a useful carrier for dexamethasone delivery. A focal brain ischemia-reperfusion model was produced by middle cerebral artery occlusion (MCAO). A heme oxygenase-1 (HO-1) expression plasmid DNA, pSV-HO-1, was delivered into the brain using R3V6-Dexa as a carrier. The pSV-HO-1/R3V6-Dexa complex was injected into the brain 1hr prior to MCAO. Twenty-four hours later, the HO-1 expression of the pSV-HO-1/R3V6-Dexa injection group was higher than those of the MCAO control, pβ-Luc/R3V6-Dexa, and pSV-HO-1/PEI25k injection groups. In addition, the infarct size was reduced due to the delivery of pSV-HO-1/R3V6-Dexa complex. Therefore, R3V6-Dexa may be a useful carrier for HO-1 gene delivery and stroke gene therapy.