Work with LifeSpan to design a custom immunohistochemistry to address your specific biological question. Outsource the entire localization process without having to
worry about finding and characterizing target specific antibodies, sourcing and validating difficult-to-find tissues, and having the ability to interpret the resulting
immunostaining in relation to complex human pathologies.
TCR Screening Services
Test your therapeutic antibodies in immunohistochemistry against a broad panel of normal frozen human tissue types in order to determine potential unintended binding.
Our non-GLP TCR services are designed on the FDA recommendation outlined in their "Points to Consider in the Manufacture and Testing of Monoclonal Antibody Products for Human Use".
Description: PX 12 is a competitive, irreversible inhibitor of thioredoxin 1 (Trx1), acting by binding to Cys73 of this enzyme. As Trx1 is overexpressed in certain cancers, PX 12 is effective in suppressing the growth of cancer cells, with growth inhibition in a panel of 60 human tumors significantly correlated with expression of Trx1 mRNA. Through its effects on Trx1, PX 12 reduces hypoxia-induced HIF-1 alpha protein levels (IC50 = 7.2 µM), as well as expression of VEGF (IC50 = 10.4 µM) and iNOS (IC50 = 18.1 µM), culminating in attenuation of the proliferation of MCF-7 cells (IC50 = 1.9 µM) and HT-29 cells (IC50 = 2.9 µM) as well as reduced microvessel density in MCF-7 tumor xenografts. PX 12 also blocks Trx-mediated activation of extracellular transglutaminase 2 (IC50 = ~3 µM) and Trx-1-increased expression and translation of CYP1B1.
PX 12 is supplied as a crystalline solid. A stock solution may be made by dissolving the PX 12 in the solvent of choice. PX 12 is soluble in organic solvents such as ethanol, DMSO, and dimethyl formamide, which should be purged with an inert gas. The solubility of PX 12 in these solvents is approximately 20, 14, and 16 mg/ml, respectively. PX 12 is sparingly soluble in aqueous solutions. To enhance aqueous solubility, dilute the organic solvent solution into aqueous buffers or isotonic saline. If performing biological experiments, ensure the residual amount of organic solvent is insignificant, since organic solvents may have physiological effects at low concentrations. We do not recommend storing the aqueous solution for more than one day.
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Jin, X., Stamnaes, J., Klöck, C., et al. Activation of extracellular transglutaminase 2 by thioredoxin. J. Biol. Chem. 286(43), 37866-37873 (2011).