Carbonic anhydrase (CA) IX overexpresses exclusively on cell membranes of hypoxic tumors, regulating the acidic tumor microenvironment. Small molecules of CA inhibitor modified with short peptide successfully achieve CA IX–targeted self-assembly that localizes CA inhibitors on hypoxic cancer cell surfaces and enhances their inhibition efficacy and selectivity. CA IX–related endocytosis also promotes selective intracellular uptake of these nanofibers under hypoxia, in which nanofiber structures increase in size with decreasing pH. This effect subsequently causes intracellular acid vesicle damage and blocks protective autophagy. The versatility of tunable nanostructures responding to cell milieu impressively provokes selective toxicities and provides strategic therapy for hypoxic tumors. Moreover, in vivo tests demonstrate considerable antimetastatic and antiangiogenesis effects in breast tumors, and particularly remarkable enhancement of antitumor efficacy in doxorubicin administration. With its biocompatible components and distinctive hypoxia therapies, this nanomaterial advances current chemotherapy, providing a new direction for hypoxic cancer therapy.
Four new cadmium(II) coordination polymers (CPs), {[Cd(Hpptpd)(H2bptta)]·8H2O} n (1), {[Cd2(Hpptpd)2(bptta)(H2O)2]·4H2O} n (2), {[Cd2(pptpz)(bpta)(H2O)]·H2O} n (3), and {[Cd(Hpptpz)(bpba)]·2H2O} n (4) (Hpptpd = 2-(3-(4-(pyridin-4-yl)phenyl)-1H-1,2,4-triazol-5-yl)pyridine, Hpptpz = 2-(3-(4-(pyridin-4-yl)phenyl)-1H-1,2,4-triazol-5-yl)pyrazine, H4bptta = 3,3′,5,5′-biphenyltetracarboxylic acid, H3bpta = 3,4′,5-biphenyltricarboxylic acid, H2bpba = 3,4′-biphenylbicarboxylic acid), were synthesized under hydrothermal conditions. The CPs were structurally characterized by single-crystal X-ray diffraction analyses and further characterized by infrared spectra (IR), elemental analyses, powder X-ray diffraction (PXRD), and thermogravimetric analyses (TGA). Complex 1 exhibits an unusual 2D + 2D → 2D parallel interpenetrated 63-hcb network. The adjacent 2D networks are interdigitated with each other to form the resulting three-dimensional (3D) supramolecular architecture through the interbilayer π···π stacking between Hpptpd ligands and nonclassical C–H···O hydrogen bonds. Complex 2 is a one-dimensional (1D) molecular ladder along the a direction and further extended via hydrogen bonds into the 3D supramolecular framework. Complex 3 exhibits a novel complicated 3D (3,4,4,5)-connected framework with the Schläfli symbol of (4·65)(4·67·82)(63)(64·82). Complex 4 manifests an intriguing layered structure with 5-connected cadmium atom as a unique node and can be simplified to an Archimedean (33·44·53) cem topology with triangular and rectangular circuits. The topology of 4 could be alternately simplified to a 3,4-connected binodal layer with a V2O5-type network. The thermal stabilities and photoluminescence behaviors of them were also discussed.
The development of an intelligent biomaterial system that can efficiently accumulate at the tumor site and release a drug in a controlled way is very important for cancer chemotherapy. PEG is widely selected as a hydrophilic shell to acquire prolonged circulation time and enhanced accumulation at the tumor site, but it also restrains the cellular transport and uptake and leads to insufficient therapeutic efficacy. In this work, a PEG-detachable pH-responsive polymer that forms micelles from copolymer cholesterol grafted poly(ethylene glycol) methyl ether-Dlabile -poly(β-amino ester)-Dlabile -poly(ethylene glycol) methyl ether (MPEG-Dlabile -PAE-g-Chol) is developed to overcome the aforementioned challenges based on pH value changes among normal physiological, extracellular (pHe), and intracellular (pHi) environments. PEGylated doxorubicin (DOX)-loaded polymeric micelles (DOX-PMs) can accumulate at the tumor site via an enhanced permeability and retention effect, and the PEG shell is detachable induced by cleavage of the pHe-labile linker between the PEG segment and the main chain. Meanwhile, the pHi-sensitive poly(β-amino ester) segment is protonated and has a high positive charge. The detachment of PEG and protonation of PAE facilitate cellular uptake of DOX-PMs by negatively charged tumor cells, along with the escape from endo-/lysosome due to the “proton-sponge” effect. The DOX molecules are controlled release from the carriers at specific pH values. The results demonstrate that DOX-PMs have the capability of showing high therapeutic efficacy and negligible cytotoxicity compared with free DOX in vitro and in vivo. Overall, we anticipate that this PEG-detachable and tumor-acidity-responsive polymeric micelle can mediate effective and biocompatible drug delivery “on demand” with clinical application potential.
The ophthalmic drug delivery is a challenge in the clinical treatment of ocular diseases. The traditional drug administration usually shows apparent limitations, such as the low bioavailability from the reason of low penetration of the cornea and the short survival time of drug in the eyes. To overcome these shortcomings, we propose an amphiphilic polymer micelle modified with hyaluronic acid (HA) for high efficient ophthalmic delivery of genistein, a widely used hydrophobic drug for treatment of ocular angiogenesis. The MPEG-b-PAE copolymer was synthesized by the Michael addition reaction, and the final drug carrier MPEG-b-PAE-g-HA was obtained by the process of esterification. Then, genistein was packaged in this drug carrier, getting the final micelles with size of about 84.5 nm. The cell viability tests showed that the micelles take no obvious cytotoxicity to the human cornea epithelium cells. The functionalities of drug slow release and cornea penetration ability were demonstrated in a series ex vivo experiments. Further, the vascular inhibition test illustrated that the micelles could significantly inhibit the angiogenesis of human umbilical vein endothelial cells. These results indicate that the constructed polymer has high feasibility to be used as drug carrier in the treatment of ocular diseases.
Eight new Zn(II) coordination polymers based on flexible 1,4-di(1H-imidazol-1-yl)butane and different dicarboxylates, [Zn(dimb)(suc)·2DMF]n (1), [Zn(dimb)(mbda)·3H2O]n (2), [Zn(dimb)(adip)·DMF·2H2O]n (3), [Zn(dimb)(pma)·2.5H2O]n (4), [Zn2(dimb)(tha)2(H2O)]n (5), [Zn(dimb)(chda)·2H2O]n (6), [Zn(dimb)(obda)·DMF]n (7), [Zn(dimb)(tdga)·CH3OH]n (8) (dimb = 1,4-di(1H-imidazol-1-yl)butane, H2suc = succinic acid, H2mbda = m-benzenediacetic acid, H2adip = adipic acid, H2pma = pimelic acid, H2tha = thiophene-2,5-dicarboxylic acid, H2chda = 1,4-cyclohexanedicarboxylic acid, H2obda = o-benzenediacetic acid, H2tdga = thiodiglycolic acid; DMF = N,N'-dimethylformamide), have been synthesized and structurally characterized by single-crystal X-ray diffraction analyses, and further characterized by infrared spectra (IR), elemental analyses, powder X-ray diffractions (PXRD) and thermogravimetric analyses (TGA). Single-crystal X-ray diffraction analysis reveals that 1, 2, 4, 7 and 8 are 2D wavy 4(4)-sql networks with different dimensions of quadrilateral window units, depending on the conformation and length of dimb and dicarboxylates. Complex 3 is a 2D a 6(3)-hcb network incorporating a [Zn2(dimb)2] cyclic subunit. In complex 5, Zn(II) centers as 3-connected node are linked by dimb and tha to form a 3D 8-fold interpenetrating ThSi2 network. Complex 6 is a 4-connected noninterpenetrating cds network. Interestingly, an infinite T4(2)6(2) water tape and a D2h cyclic water tetramer are also found in complexes 2 and 3, respectively. In 1-8, all Zn(II) centers are located in a four-coordinated environment, and dimb and dicarboxylates are 2-connected linkers, but networks with diverse topologies are built, which indicates the linkage of central metal ion, the conformation of dimb and dicarboxylate have important influences on the resulting structures. Furthermore, the solid-state photoluminescence properties of the 1-8 were investigated at 298 and 77 K.
ObjectiveLiver regeneration remains one of the biggest clinical challenges. Here, we aim to transform the spleen into a liver-like organ via directly reprogramming the splenic fibroblasts into hepatocytes in vivo.DesignIn the mouse spleen, the number of fibroblasts was through silica particles (SiO2) stimulation, the expanded fibroblasts were converted to hepatocytes (iHeps) by lentiviral transfection of three key transcriptional factors (Foxa3, Gata4 and Hnf1a), and the iHeps were further expanded with tumour necrosis factor-α (TNF-α) and lentivirus-mediated expression of epidermal growth factor (EGF) and hepatocyte growth factor (HGF).ResultsSiO2 stimulation tripled the number of activated fibroblasts. Foxa3, Gata4 and Hnf1a converted SiO2-remodelled spleen fibroblasts into 2×106 functional iHeps in one spleen. TNF-α protein and lentivirus-mediated expression of EGF and HGF further enabled the total hepatocytes to expand to 8×106 per spleen. iHeps possessed hepatic functions—such as glycogen storage, lipid accumulation and drug metabolism—and performed fundamental liver functions to improve the survival rate of mice with 90% hepatectomy.ConclusionDirect conversion of the spleen into a liver-like organ, without cell or tissue transplantation, establishes fundamental hepatic functions in mice, suggesting its potential value for the treatment of end-stage liver diseases.
Background Honeysuckle is a time‐honored herb with anticancer activity in traditional Chinese medicine. Recently, accumulating reports are suggesting that the microRNAs in this medicinal plant not only play a physiological role in their original system, but also can be transmitted to another species as potential therapeutic components. In the numerous bioactive investigations, the anti-tumor effects of these microRNAs in the magical herb are rarely studied, especially the special miR2911, a honeysuckle-encoded atypical microRNA, with high stability during the boiling process and unique biological activity to target TGF-β1 mRNA. Methods Luciferase assay was conducted to test the ability of miR2911 to target TGF-β1 mRNA. ELISA was performed to determine the expression level of TGF-β1 of mouse colorectal adenocarcinoma CT26 cells when treated with miR2911 and tumor tissue in Sidt1+/+ and Sidt1−/− mice. qRT-PCR was performed to examine the level of expression of miR2911. Tumor-bearing wild and nude mice were employed to evaluate the anti-tumor effect of honeysuckle and miR2911 in vivo. Tumor tissue necrosis was observed by H&E staining. Besides, the infiltration of T lymphocytes across solid tumors was tested by immunostaining staining. Results Our results showed that honeysuckle slowed the development of colon cancer down. Further research showed that miR2911 could bind strongly to TGF-β1 mRNA and down-regulate the expression of TGF-β1 and had a high stability under boiling and acid condition. Moreover, SIDT1 mediated dietary miR2911 inter-species absorption. And we found that miR2911 had a similar anticancer effect as honeysuckle. Mechanistically, miR2911 reversed the tumor-promoting effect of TGF-β1 by an increase of T lymphocytes infiltration, resulting in slowing the colon cancer process in immunocompetent mice. Consistent with this inference, the anti-tumor effect of miR2911 was revealed to be abolished in T cell immune deficiency mice. Conclusion Taken together, honeysuckle-derived miR2911 showed an anti-tumor effect in colon cancer through targeting TGF-β1 mRNA. The down-regulation of TGF-β1 promoted T lymphocytes infiltration, and accordingly impeded the colon tumor development.
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