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Hosung Min

Publications and source records attributed to Hosung Min.

3 recordsLinked to original sources

Functional GPCR microarrays.

This paper describes G-protein-coupled receptor (GPCR) microarrays on porous glass substrates and functional assays based on the binding of a europium-labeled GTP analogue. The porous glass slides were made by casting a glass frit on impermeable glass slides and then coating with gamma-aminopropyl silane (GAPS). The emitted fluorescence was captured on an imager with a time-gated intensified CCD detector. Microarrays of the neurotensin receptor 1, the cholinergic receptor muscarinic 2, the opioid receptor mu, and the cannabinoid receptor 1 were fabricated by pin printing. The selective agonism of each of the receptors was observed. The screening of potential antagonists was demonstrated using a cocktail of agonists. The amount of activation observed was sufficient to permit determinations of EC50 and IC50. Such microarrays could potentially streamline drug discovery by helping integrate primary screening with selectivity and safety screening without compromising the essential functional information obtainable from cellular assays.

Drug Evaluation, Preclinical↗

Suppression of angiogenesis and tumor growth by selective inhibition of angiopoietin-2.

Angiopoietin-2 (Ang2) exhibits broad expression in the remodeling vasculature of human tumors but very limited expression in normal tissues, making it an attractive candidate target for antiangiogenic cancer therapy. To investigate the functional consequences of blocking Ang2 activity, we generated antibodies and peptide-Fc fusion proteins that potently and selectively neutralize the interaction between Ang2 and its receptor, Tie2. Systemic treatment of tumor-bearing mice with these Ang2-blocking agents resulted in tumor stasis, followed by elimination of all measurable tumor in a subset of animals. These effects were accompanied by reduced endothelial cell proliferation, consistent with an antiangiogenic therapeutic mechanism. Anti-Ang2 therapy also prevented VEGF-stimulated neovascularization in a rat corneal model of angiogenesis. These results imply that specific Ang2 inhibition may represent an effective antiangiogenic strategy for treating patients with solid tumors.

Angiopoietin-2↗

The candidate neuroprotective agent artemin induces autonomic neural dysplasia without preventing peripheral nerve dysfunction.

Artemin (ART) signals through the GFR alpha-3/RET receptor complex to support sympathetic neuron development. Here we show that ART also influences autonomic elements in adrenal medulla and enteric and pelvic ganglia. Transgenic mice over-expressing Art throughout development exhibited systemic autonomic neural lesions including fusion of adrenal medullae with adjacent paraganglia, adrenal medullary dysplasia, and marked enlargement of sympathetic (superior cervical and sympathetic chain ganglia) and parasympathetic (enteric, pelvic) ganglia. Changes began by gestational day 12.5 and formed progressively larger masses during adulthood. Art supplementation in wild type adult mice by administering recombinant protein or an Art-bearing retroviral vector resulted in hyperplasia or neuronal metaplasia at the adrenal corticomedullary junction. Expression data revealed that Gfr alpha-3 is expressed during development in the adrenal medulla, sensory and autonomic ganglia and their projections, while Art is found in contiguous mesenchymal domains (especially skeleton) and in certain nerves. Intrathecal Art therapy did not reduce hypalgesia in rats following nerve ligation. These data (1) confirm that ART acts as a differentiation factor for autonomic (chiefly sympathoadrenal but also parasympathetic) neurons, (2) suggest a role for ART overexpression in the genesis of pheochromocytomas and paragangliomas, and (3) indicate that ART is not a suitable therapy for peripheral neuropathy.

Adult↗