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Breast cancer holds the highest incidence rate among women. Doxorubicin (DOX) is a potent frontline drug for the treatment of breast cancer. The anticancer mechanisms of DOX include inducing immunogenic cell death in tumor cells, causing damage to tumor DNA, and generating free radicals. However, its pharmacological efficacy and wide use are restricted by its substantial dose-dependent side effects. We have recently revealed that 1,7-Heptanediol (1,7-Hept) severely impairs the bioenergetics and metabolism of aggressive human cancer cells. In the present work, we prepared liposomes co-loaded with DOX and 1,7-Hept (DOX/1,7-Hept-lipo) and assessed their potential synergistic anti-tumor effects. In vitro studies demonstrated that 4T1 cells (the mouse breast cancer cell) exhibited higher sensitivity to 1,7-Hept and DOX/1,7-Hept-lipo could induce ICD of 4T1 cells. Cell viability was markedly reduced when 4T1 cells were treated with a combination of DOX and 1,7-Hept. In a mouse breast cancer model, the DOX/1,7-Hept-lipo exhibited superior anti-tumor efficacy compared to liposomes loaded with individual drugs, resulting in almost total elimination of the tumors at lower doses of DOX with reduced systemic toxicity. Notably, the number of immune cells significantly increased in the tumor microenvironment, and macrophages were more transformed into the anti-tumor M1 phenotype. Our findings suggest strong synergistic anti-tumor effects of DOX and 1,7-Hept, enhancing the efficacy of tumor immunotherapy and mitigating the toxic side effects of DOX., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

It has been questioned as to whether polyplexes in the cytoplasm can reach the nuclear compartment and if so in what form. By applying atomic force microscopy (AFM) to the nuclear envelope and the nuclear pore complexes, we demonstrate that disposition of polyethylenimine (PEI)/DNA polyplexes that were microinjected into the oocytes of Xenopus laevis, as an example of a non-dividing cell, is exclusive to the nuclear pore complex (NPC). AFM images show NPCs clogged only with sub-50nm polyplexes. This mode of disposition neither altered the morphology/integrity of the nuclear membrane nor the NPC. AFM images further show polyplexes on the nucleoplasmic side of the envelope, presumably indicating species in transit. Transmission electron microscopy studies of ruptured nuclei from transfected human cell lines demonstrate the presence of sub-50nm particles resembling polyplexes in morphology compared with control preparations., (Copyright © 2016. Published by Elsevier B.V.)

Nuclear pore complexes (NPCs) mediate all transport between the cytosol and the nucleus highly selectively. Their selectivity can become an insurmountable hurdle for exogenously applied therapeutic macromolecules. Many viruses naturally overcome the NPC barrier. Therefore, gene therapy often utilizes viral particles as nano-carriers for exogenous therapeutic macromolecules. Viral gene therapy, however, frequently leads to severe adverse effects. We intend to elucidate the mechanisms underlying controlled release of viral DNA at the NPC in order to design new non-viral approach for intranuclear DNA delivery. For this purpose, we developed a comprehensive experimental strategy combining nano-imaging and biochemical methods. Here, we apply Herpes simplex virus type 1 (HSV-1) as an ideal example. HSV-1 contains its long 145kbp DNA in a capsid which is merely 125nm in size. The capsid shields and targets the DNA specifically to the NPC. Only at the NPC, the capsid releases the DNA for nuclear delivery. The underlying mechanisms of this multi-step process remain unresolved. In this work we follow the fate of HSV-1 DNA in the process of transit across the NPC. Our results indicate an involvement of hydrophobicity for capsid opening. Furthermore, the DNA is presumably released as a single thread. We assume that it penetrates the NPC in this conformation. It is compacted by the host intranuclear proteins once it reaches the interior of the nucleus. Our proposed experimental strategy can be extended to other viruses. Moreover, our observations may help design potent non-viral based nano-carriers for gene therapy., (Copyright © 2013 Elsevier B.V. All rights reserved.)

The efficiency of gene therapy in non-dividing cells is particularly poor due to restricted nuclear delivery rates of exogenously applied macromolecules across the nuclear pore complexes (NPCs). Therefore, improved intranuclear delivery of transgenes requires an ability to modulate the barrier function of the NPC. Despite a large body of experimental evidence accumulated to date, the contribution of individual NPC proteins (nucleoporins) to the formation of the NPC permeability barrier as well as their structural organization within the NPC remains under debate. In the present study, we revisit the view on the spatial arrangement of the Phe-Gly rich domains (FG-domains) of a subset of nucleoporins known as FG-nucleoporins. They are generally believed to be the key constituents of the NPC permeability barrier. Comparison of the binding pattern of a transport receptor importin β fragment, that binds specifically to FG-domains, with the binding pattern of wheat germ agglutinin that binds elsewhere in the NPC, reveals that FG-domains tend to cluster in the very center of the NPC. Furthermore, a controlled sequential release of the barrier-forming nucleoporins results in a gradual breakdown of the NPC permeability barrier. The breakdown is initiated by a dissociation of Nup62 from the NPC. This is accompanied by an increased passive diffusion of small molecules across the NPC. Subsequent dissociation of Nup98 and possibly other nucleoporins results in a collapse of the barrier for larger molecules. We therefore conclude that FG-nucleoporins do not contribute equally to the maintenance of the NPC permeability barrier exclusion limit. This implies that a controlled release of nucleoporins that contribute most to the formation and maintenance of the NPC barrier can facilitate access of therapeutic macromolecules into the nucleus., (Copyright © 2012 Elsevier B.V. All rights reserved.)