Tumor accumulation of protein kinase-responsive gene carrier/DNA polyplex stabilized by alkanethiol for intravenous injection

Abstract

We synthesized polymeric gene carriers consisting of poly-L-lysine (PLL) main chain modified both with substrate peptide for protein kinase Cα (PKCα) and alkanethiol (pentadecanethiol). Due to the grafted substrate peptide, the polyplex prepared from these carriers is expected to show gene expression triggered by the phosphorylation of the peptide by intracellular PKCα. The modified alkanethiol on the main chain stabilized the polyplex both via disulfide crosslinking and hydrophobic interaction. The polyplex found to show gene expression in vitro when the alkanethiol content in the main chain was enough low (4-mol%-modification of PLL's ε-amine group) to minimize cytotoxic effect. Even though the content of alkanethiol is low, the polyplex had significant stability in a model serum solution and showed longer blood circulation in vivo. The polyplex clearly accumulated in tumor after intravenous injection.

Peptide-Grafted Polymers as Artificial Converter of Cellular Signals

“…Thus, long alkane thiol (mercaptopalmitic acid 4.4 mol %) and PKCα specific substrate peptide (5 mol %) were incorpo- rated into poly-L-lysine (PLL) for a D-RECS system for intravenous injection (Figure 11a). 38 The alkane thiol suppressed aggregation of polyplex between this polymer and plasmid DNA in serum conditions in contrast to peptide grafted PLL without alkane thiol (Figure 11b). Biodistribution of polyplex in tumor bearing mice using Cy5 labeled plasmid demonstrated the effectiveness of this strategy for the stabilization of polymer/DNA polyplex nanoparticle (Figure 11c).…”

Smart stimuli-responsive drug delivery systems in spotlight of COVID-19

“… AFM, XPS, Cell cytotoxicity, CLSM, flow cytometry analysis [85] Phe-Phe Prodrugs MTX Osteoarthritis Enzymatic cleavage of MTX In vitro inhibition of the proliferation of human fibroblast-like synoviocytes, in vivo inhibition of the knee swelling of rats/ Intraarticular 1H NMR, GPC analysis, Cathepsin fragmentation, LC–MS [25] Furin GRVRRSC Triterpenine-based liposomal complex (PEGcleavable Tf-CTM/L) Tripterine Cervical cancer Passive diffusion; furin-cleavable PEG shell improves accumulation at the tumor site by steric hindrance In vitro in HeLa cells, in vivo in Nude mice/ Intraperitoneal DLS, TEM, in vitro drug release, flow cytometry, Cellular uptake, Cellular apoptosis, MTT assay, immunohistochemistry tests, CD-31 and a-SMA assay [86] RVRRSK RX(K/R)RY Graphene-based co-delivery nanocapsules DOX and TRAIL Cancer TRAIL is released extracellularly by furin-associated cleavage, and DOX is released by acidity responsive In vitro in A549 cells AFM, In vitro release, CLSM [87] Protein kinase Cα FKKQGSFAKKK-NH 2 Polymeric gene carriers consisting of PLL DNA polyplex pDNA Cancer Intracellular PKCα phosphorylated the peptide and triggered the gene expression In vitro in A549 cells, in vivo in male mice via the tail veins/ i.v. 1 H NMR, titration assay, DLS, Agarose gel electrophoresis, Cytotoxicity assay, Transfection study [88] HFKKQGSFAKKK-NH2 NPs pDNA Cancer PKCα targeted the grafted cationic peptides and decreased their cationic charge, resulting in the release of pDNA from the polyplex In vitro in B16 melanoma cells, in vivo in mice/ Microinjection DLS, coupled enzyme assay, cytotoxicity test, microinjection study, Transfection study, western blotting assay [89] Caspase-3 DEVD (Asp-Glu-Val-Asp) NPs …”