In Vivo Gold Complex Catalysis within Live Mice Tsubokura, Kazuki; Vong, Kenward K. H.; Pradipta, Ambara R. ...
Angewandte Chemie International Edition,
March 20, 2017, Letnik:
56, Številka:
13
Journal Article
Recenzirano
Metal complex catalysis within biological systems is largely limited to cell and bacterial systems. In this work, a glycoalbumin–AuIII complex was designed and developed that enables organ‐specific, ...localized propargyl ester amidation with nearby proteins within live mice. The targeted reactivity can be imaged through the use of Cy7.5‐ and TAMRA‐linked propargyl ester based fluorescent probes. This targeting system could enable the exploitation of other metal catalysis strategies for biomedical and clinical applications.
The first metal‐catalyzed reaction that proceeds within live mice is based on a targeting approach with glycans. Glycoalbumin–AuIII complexes can be accumulated in specific organs where they catalyze amide bond formation between a propargyl ester probe and amine groups on nearby proteins. The selective targeting was confirmed by whole body fluorescence imaging and analysis of dissected tissues.
Display omitted
Acrolein, a highly reactive α,β-unsaturated aldehyde, is a compound to which humans are exposed in many different situations and often causes various human diseases. This paper ...summarizes the reports over the past twenty-five years regarding disease-associated acrolein detected in clinical patients and the role acrolein plays in various diseases. In several diseases, it was found that the increased acrolein acts as a pathogenetic factor. Thus, we propose the utility of over-produced acrolein as a substrate for a promising therapeutic or diagnostic method applicable to a wide range of diseases based on an in vivo synthetic chemistry strategy.
This study proposes a new method for radionuclide therapy that involves the use of oligomeric 2,6-diisopropylphenyl azides and a chelator to form stable complexes with metallic radionuclides. The ...technique works by taking advantage of the endogenous acrolein produced by cancer cells. The azides react with the acrolein to give a diazo derivative that immediately attaches to the nearest organelle, effectively anchoring the radionuclide within the tumor. Preliminary
experiments were conducted on a human lung carcinoma xenograft model, demonstrating the feasibility of this approach for cancer treatment.
Display omitted
Amyloid aggregates of proteins are known to be involved in various diseases such as Alzheimer's disease (AD). It is therefore speculated that the inhibition of amyloid formation can ...play an important role in the prevention of various diseases involving amyloids. Recently, we have found that acrolein reacts with polyamines, such as spermine, and produces 1,5-diazacyclooctane, such as cyclic spermine (cSPM). cSPM could suppress the aggregation of amyloid β 1–40 (Aβ40), one of the causative proteins of AD. This result suggests the potential inhibitory effect of cSPM against Aβ 1–42 (Aβ42) and other amyloid protein aggregation which are the main pathological features of AD and other diseases. However, the effect on the aggregation of such proteins remains unclear. In this study, the effect of cSPM on the amyloid formation of Aβ42, amylin, and insulin was investigated. These three amyloidogenic proteins forming amyloids under physiological conditions (pH 7.4 and 37℃) served as model and are thought to be the causative proteins of AD, type 2 diabetes, and insulin-derived amyloidosis, respectively. Our results indicate that cSPM can suppress the amyloid aggregation of these proteins and reduce cytotoxicity. This study contributes to a better understanding of means to potentially counteract diseases by the means of polyamine and acrolein.
Abstract Methods for producing drugs directly at the cancer site, particularly using bioorthogonal metal catalysts, are being explored to mitigate the side effects of therapy. Albumin‐based ...artificial metalloenzymes (ArMs) catalyze reactions in living mice while protecting the catalyst in the hydrophobic pocket. Here, we describe the in situ preparation and application of biocompatible tumor‐targeting ArMs using circulating albumin, which is abundant in the bloodstream. The ArM was formed using blood albumin through the intravenous injection of ruthenium conjugated with an albumin‐binding ligand; the tumor‐targeting unit was conjugated to the ArM using its catalytic activity, and the ArM was transported to the cancer site. The delivered ArM catalyzed a second tagging reaction of the proapoptotic peptide on the cancer surface, successfully suppressing cancer proliferation. This approach, which efficiently leveraged the persisting reactivity twice in vivo, holds promise for future in vivo metal‐catalyzed drug synthesis utilizing endogenous albumin.
Cytotoxic anticancer drugs used in chemotherapy are often antiproliferative agents that preferentially kill rapidly growing cancer cells. Their mechanism relies mainly on the enhanced proliferation ...rate of cancer cells and is not genuinely selective for cancer cells. Therefore, these drugs can also significantly affect healthy cells. Prodrug therapy provides an alternative approach using a less cytotoxic form of anticancer drug. It involves the synthesis of inactive drug derivatives which are converted to an active form inside the body and, preferably, only at the site of cancerous tissues, thereby reducing adverse drug reaction (ADR) events. Herein, we demonstrate a prodrug activation strategy by utilizing the reaction between aryl azide and endogenous acrolein. Since acrolein is generally overproduced by most cancer cells, we anticipate our strategy as a starting point for further applications in mouse models with various cancers. Furthermore, cancer drugs that have had therapeutic index challenges might be reconsidered for application by utilizing our strategy.
Prodrug activation strategy by utilizing the reaction between aryl azide and endogenous acrolein that is generally overproduced by cancer cells.
TRAF6 is highly expressed in many tumors and plays an important role in the immune system. The aim of this study is to confirm anti-tumor activities of all naturally occurring Cinchona alkaloids that ...have been screened using computational docking program, and to validate the accuracy and specificity of the RING domain of TRAF6 as a potential anti-tumor target, and to explore their effect on the immune system. Results reported herein would demonstrate that Cinchona alkaloids could induce apoptosis in HeLa cells, inhibit the ubiquitination and phosphorylation of both AKT and TAK1, and up-regulate the ratio of Bax/Bcl-2. In addition, these compounds could induce apoptosis in vivo, and increase the secretion of TNF-α, IFN-γ, and IgG, while not significantly impacting the ratio of CD4
T/CD8
T. These investigations suggest that the RING domain of TRAF6 could serve as a de novo biological target for therapeutic treatment in cancers.
Display omitted
Tetramethylrhodamine (TAMRA)-phenyl azide is a chemical probe used to detect intracellular acrolein directly in live cells. Herein, we demonstrated that TAMRA is the optimum ...fluorophore for the probe. TAMRA-phenyl azide was used to reveal that high levels of acrolein are generated in a variety of breast cancer cells, regardless of the tumor subtype. These findings corroborate the analysis presented in our previous report, in which TAMRA-phenyl azide was used to label breast cancer tissues resected from breast cancer patients. Because high levels of acrolein were generated in all cancer cell types, we believe that acrolein detection may be useful as a general method for labeling cancerous tissues.
Cells are covered with a thick layer of sugar molecules known as glycans. Abnormal glycosylation is a hallmark of cancer, and hypersialylation increases tumor metastasis by promoting immune evasion ...and inducing tumor cell invasion and migration. Inhibiting sialylation is thus a potential anticancer treatment strategy. However, targeting sialic acids is difficult because of the lack of selective delivery tools. Here, we present a prodrug strategy for selectively releasing the global inhibitor of sialylation peracetylated 3F
ax
-Neu5Ac (PFN) in cancer cells using the reaction between phenyl azide and endogenous acrolein, which is overproduced in most cancer cells. The prodrug significantly suppressed tumor growth in mice as effectively as PFN without causing kidney dysfunction, which is associated with PFN. The use of sialylated glycans as immune checkpoints is gaining increasing attention, and the proposed method for precisely targeting aberrant sialylation provides a novel avenue for expanding current cancer treatments.
Chemical regulation of glycan synthesis at the targeted cancer cell surface in mice leading to significant anticancer effects without side effects.
Peptidoglycan (PGN) is a major component of bacterial cell wall and is recognized as a potent immunostimulant. The PGN in the cell envelope of Mycobacterium Tuberculosis has been shown to possess ...several unique characteristics including the presence of N-glycolyl groups (in addition to N-acetyl groups) in the muramic acid residues, and amidation of the free carboxylic acid of d-Glu or of meso-DAP in the peptide chains. Using a newly developed, highly stereoselective, chemoenzymatic approach for the synthesis of meso-DAP in peptide stems, we successfully synthesized for the first time, a series of Mycobacterium PGN fragments that include both mono- and disaccharides of MurNGlyc or 1,6-anhydro-MurNGlyc, as well as peptide-amidated variants. The ability of these PGN fragments to stimulate the immune system through activation of human Nod1 and Nod2 was examined. The PGN fragments were found to modulate immune stimulation, specifically, amidation at the d-Glu and meso-DAP in the peptide stem strongly reduced hNod1 activation. This effect was dependent on modification position. Additionally, N-glycolyl (instead of acetyl) of muramic acid was associated with slightly reduced human Nod1 and Nod2 stimulatory capabilities.
PDF
