6 research outputs found
<i>In Situ</i> Amplification of Intracellular MicroRNA with MNAzyme Nanodevices for Multiplexed Imaging, Logic Operation, and Controlled Drug Release
MicroRNAs (miRNAs), as key regulators in gene expression networks, have participated in many biological processes, including cancer initiation, progression, and metastasis, indicative of potential diagnostic biomarkers and therapeutic targets. To tackle the low abundance of miRNAs in a single cell, we have developed programmable nanodevices with MNAzymes to realize stringent recognition and <i>in situ</i> amplification of intracellular miRNAs for multiplexed detection and controlled drug release. As a proof of concept, miR-21 and miR-145, respectively up- and down-expressed in most tumor tissues, were selected as endogenous cancer indicators and therapy triggers to test the efficacy of the photothermal nanodevices. The sequence programmability and specificity of MNAzyme motifs enabled the fluorescent turn-on probes not only to sensitively profile the distributions of miR-21/miR-145 in cell lysates of HeLa, HL-60, and NIH 3T3 (9632/0, 14147/0, 2047/421 copies per cell, respectively) but also to visualize trace amounts of miRNAs in a single cell, allowing logic operation for graded cancer risk assessment and dynamic monitoring of therapy response by confocal microscopy and flow cytometry. Furthermore, through general molecular design, the MNAzyme motifs could serve as three-dimensional gatekeepers to lock the doxorubicin inside the nanocarriers. The drug nanocarriers were exclusively internalized into the target tumor cells <i>via</i> aptamer-guided recognition and reopened by the endogenous miRNAs, where the drug release rates could be spatial-temporally controlled by the modulation of miRNA expression. Integrated with miRNA profiling techniques, the designed nanodevices can provide general strategy for disease diagnosis, prognosis, and combination treatment with chemotherapy and gene therapy
Corona-Directed Nucleic Acid Delivery into Hepatic Stellate Cells for Liver Fibrosis Therapy
Strategies to modify nanoparticles with biological ligands for targeted drug delivery <i>in vivo</i> have been widely studied but met with limited clinical success. A possible reason is that, in the blood circulation, serum proteins could rapidly form a layer of protein “corona” on the vehicle surface, which might block the modified ligands and hamper their targeting functions. We speculate that strategies for drug delivery can be designed based upon elegant control of the corona formation on the vehicle surfaces. In this study, we demonstrate a retinol-conjugated polyetherimine (RcP) nanoparticle system that selectively recruited the retinol binding protein 4 (RBP) in its corona components. RBP was found to bind retinol, and direct the antisense oligonucleotide (ASO)-laden RcP carrier to hepatic stellate cells (HSC), which play essential roles in the progression of hepatic fibrosis. In both mouse fibrosis models, induced by carbon tetrachloride (CCl<sub>4</sub>) and bile duct ligation (BDL), respectively, the ASO-laden RcP particles effectively suppressed the expression of type I collagen (collagen I), and consequently ameliorated hepatic fibrosis. Such findings suggest that this delivery system, designed to exploit the power of corona proteins, can serve as a promising tool for targeted delivery of therapeutic agents for the treatment of hepatic fibrosis
Near Infrared-Guided Smart Nanocarriers for MicroRNA-Controlled Release of Doxorubicin/siRNA with Intracellular ATP as Fuel
In chemotherapy, it is a great challenge
to recruit endogenous
stimuli instead of external intervention for targeted delivery and
controlled release; microRNAs are the most promising candidates due
to their vital role during tumorigenesis and significant expression
difference. Herein, to amplify the low abundant microRNAs in live
cells, we designed a stimuli-responsive DNA Y-motif for codelivery
of siRNA and Dox, in which the cargo release was achieved <i>via</i> enzyme-free cascade amplification with endogenous microRNA
as trigger and ATP (or H<sup>+</sup>) as fuel through toehold-mediated
strand displacement. Furthermore, to realize controlled release in
tumor cells, smart nanocarriers were constructed with stimuli-responsive
Y-motifs, gold nanorods, and temperature-sensitive polymers, whose
surfaces could be reversibly switched between PEG and RGD states <i>via</i> photothermal conversion. The PEG corona kept the nanocarriers
stealth during blood circulation to protect the Y-motifs against nuclease
digestion and enhance passive accumulation, whereas the exposed RGD
shell under near-infrared (NIR) irradiation at tumor sites facilitated
the specific receptor-mediated endocytosis by tumor cells. Through
modulating NIR laser, microRNA, or ATP expressions, the therapy efficacies
to five different cell lines were finely controlled, presenting NIR-guided
accumulation, massive release, efficient gene silence, and severe
apoptosis in HeLa cells; <i>in vivo</i> study showed that
a low dosage of nanocarriers synergistically inhibited the tumor growth
by silencing gene expression and inducing cell apoptosis under mild
NIR irradiation, though they only brought minimum damage to normal
organs. The combination of nanomaterials, polymers, and DNA nanomachines
provided a promising tool for designing smart nanodevices for disease
therapy
Additional file 1: Table S1. of miR-124-3p functions as a tumor suppressor in breast cancer by targeting CBL
Patientsâ Characteristics. (DOCX 17 kb
Additional file 2: Figure S1. of miR-124-3p functions as a tumor suppressor in breast cancer by targeting CBL
Downregulation of CBL by siRNA and upregulation of CBL by an overexpression plasmid in MCF-7 cells. (A-C) Western blotting analysis of CBL protein levels in MCF-7 cells treated with control siRNA, CBL siRNA, control plasmid or CBL plasmid (A and B: representative image; C: quantitative analysis). *P < 0.05; **P < 0.01. (JPG 337 kb
Autophagy mediated CoCrMo particle-induced peri-implant osteolysis by promoting osteoblast apoptosis
<p>Wear particle-induced osteolysis is the leading cause of aseptic loosening, which is the most common reason for THA (total hip arthroplasty) failure and revision surgery. Although existing studies suggest that osteoblast apoptosis induced by wear debris is involved in aseptic loosening, the underlying mechanism linking wear particles to osteoblast apoptosis remains almost totally unknown. In the present study, we investigated the effect of autophagy on osteoblast apoptosis induced by CoCrMo metal particles (CoPs) in vitro and in a calvarial resorption animal model. Our study demonstrated that CoPs stimulated autophagy in osteoblasts and PIO (particle-induced osteolysis) animal models. Both autophagy inhibitor 3-MA (3-methyladenine) and <i>siRNA</i> of <i>Atg5</i> could dramatically reduce CoPs-induced apoptosis in osteoblasts. Further, inhibition of autophagy with 3-MA ameliorated the severity of osteolysis in PIO animal models. Moreover, 3-MA also prevented osteoblast apoptosis in an antiautophagic way when tested in PIO model. Collectively, these results suggest that autophagy plays a key role in CoPs-induced osteolysis and that targeting autophagy-related pathways may represent a potential therapeutic approach for treating particle-induced peri-implant osteolysis.</p