Tunable cytotoxic aptamer-drug conjugates for the treatment of prostate cancer.

Therapies that can eliminate both local and metastatic prostate tumor lesions while sparing normal organ tissue are desperately needed. With the goal of developing an improved drug-targeting strategy, we turned to a new class of targeted anticancer therapeutics: aptamers conjugated to highly toxic chemotherapeutics. Cell selection for aptamers with prostate cancer specificity yielded the E3 aptamer, which internalizes into prostate cancer cells without targeting normal prostate cells.

Targeted disruption of β-arrestin 2-mediated signaling pathways by aptamer chimeras leads to inhibition of leukemic cell growth.

Unlabelled: β-arrestins, ubiquitous cellular scaffolding proteins that act as signaling mediators of numerous critical cellular pathways, are attractive therapeutic targets because they promote tumorigenesis in several tumor models. However, targeting scaffolding proteins with traditional small molecule drugs has been challenging. Inhibition of β-arrestin 2 with a novel aptamer impedes multiple oncogenic signaling pathways simultaneously.

Immobilized metal-ion affinity chromatography of recombinant Fab protein OPG C11 in the presence of EDTA-Mg(II).

Undesired adsorption of host cell proteins poses a big challenge for immobilized metal-ion affinity chromatography (IMAC) purification. In this study, by using His6-tagged protein Fab OPG C11 from Escherichia coli fermentation as a model, we found that the presence of low concentrations of EDTA-Mg2+ in feed streams weakens the adsorption but makes it more specific towards polyhistidine tag. By combining EDTA-Mg2+ treatment and periplasmic extraction, we developed a one-step purification procedure for His6-tagged recombinant Fab OPG C11 using Ni-IDA (iminodiacetic acid) chromatography.