Innovative nanotechnologies for enhancing nucleic acids/gene therapy: Controlling intracellular trafficking to targeted biodistribution.

Nanomedicine promises to play an important role in next generation therapy, including Nucleic acid/Gene therapy. To accomplish this, innovative nanotechnologies will be needed to support nanomedicine by controlling not only the biodistribution but also the intracellular trafficking of macromolecules such as RNA/DNA. A multifunctional envelope-type nano device (MEND) was developed to meet this requirement. We herein provide an update regarding the functions of the MEND system focusing on the introduction of different functional biomaterials that enhance efficiency. The octaarginine (R8) peptide enhances cellular uptake and controls intracellular trafficking to induce synergism in transgene expression. The R8 was also used for developing a MITO-Porter system for mitochondrial targeting. The function of the MITO-Porter system was extended by developing a mitochondrial reporter gene for mitochondrial gene therapy. For efficient in vivo gene delivery, new pH-sensitive lipids have been introduced to achieve controlled biodistribution and to enhance endosomal escape. For example, the CL4H6 lipid exerts a more efficient in vivo gene silencing than that of ONPATTROTM, a preparation that has been approved by the US Food and Drug Administration. We further summarize new technologies that have been successfully applied to cancer immunotherapy leading to the introduction of a new strategy based on the concept of the Cancer-Immunity Cycle.

Nakamura T ，Yamada Y ，Sato Y ，Khalil IA ，Harashima H ... -  《-》

Multifunctional enveloped nanodevices (MENDs).

Sato Y ，Nakamura T ，Yamada Y ，Akita H ，Harashima H ... -  《Advances in Genetics》

A multifunctional envelope-type nanodevice for use in nanomedicine: concept and applications.

Nakamura T ，Akita H ，Yamada Y ，Hatakeyama H ，Harashima H ... -  《-》

Evolution of drug delivery system from viewpoint of controlled intracellular trafficking and selective tissue targeting toward future nanomedicine.

Due to the rapid changes that have occurred in the field of drug discovery and the recent developments in the early 21st century, the role of drug delivery systems (DDS) has become increasingly more important. For the past 20 years, our laboratory has been developing gene delivery systems based on lipid-based delivery systems. One of our efforts has been directed toward developing a multifunctional envelope-type nano device (MEND) by modifying the particle surface with octaarginine, which resulted in a remarkably enhanced cellular uptake and improved intracellular trafficking of plasmid DNA (pDNA). When we moved to in vivo applications, however, we were faced with the PEG-dilemma and we shifted our strategy to the incorporation of ionizable cationic lipids into our system. This resulted in some dramatic improvements over our original design and this can be attributed to the development of a new lipid library. We have also developed a mitochondrial targeting system based on a membrane fusion mechanism using a MITO-Porter, which can deliver nucleic acids/pDNA into the matrix of mitochondria. After the appearance of antibody medicines, Opdivo, an immune checkpoint inhibitor, has established cancer immunology as the 4th strategy in cancer therapy. Our DDS technologies can also be applied to this new field of cancer therapy to cure cancer by controlling our immune mechanisms. The latest studies are summarized in this review article.

Yamada Y ，Sato Y ，Nakamura T ，Harashima H ... -  《-》

Development of a multifunctional envelope-type nano device and its application to nanomedicine.

Successful nanomedicines should be based on sound drug delivery systems (DDS) the permit intracellular trafficking as well as the biodistribution of cargos to be controlled. We have been developing new types of DDS that are multifunctional envelope-type nano devices referred to as MENDs. First, we will focus the in vivo delivery of siRNA to hepatocytes using a YSK-MEND which is composed of pH-responsive cationic lipids. The YSK-MEND is capable of inducing efficient silencing activity in hepatocytes and can be used to cure mice that are infected with hepatitis C or B. The YSK-MEND can also be applied to cancer immunotherapy through the activation of immune cells by delivering different compounds such as cyclic-di-GMP, siRNA or alpha-galactosylceramide as a lipid antigen. The findings indicate that, as predicted, these compounds, when encapsulated in the YSK-MEND, can be delivered to the site of action and induced immune activation through different mechanisms. Finally, a MITO-Porter, a membrane fusion-based delivery system to mitochondria, is introduced as an organelle targeting DDS and a new strategy for cancer therapy is proposed by delivering gentamicin to mitochondria of cancer cells. These new technologies are expected to extend the therapeutic area of Nanomedicine by increasing the power of DDS, especially from the view point of controlled intracellular trafficking.

Sato Y ，Nakamura T ，Yamada Y ，Harashima H ... -  《-》