Oligonucleotide targeting

The antisense oligonucleotide LErafAON against the serine/threonine kinase c-Raf has been tested in phase I clinical trials. The antisense oligonucleotides ISIS-5132, which also inhibits c-Raf, and ISIS-3521, which inhibits PKC, went through different phase clinical trials with solid tumour patients. Unfortunately, no objective responses occurred with these PKI. GEM-231, an oligonucleotide targeting the RIa subunit of protein kinase A is currently undergoing phase I/II clinical trials alone or in combination with traditional therapy for the treatment of solid cancers [3]. 

W. W. Liang, X. Shi, D. Deshpande, C. J. Malanga, and Y. Rojanasakul, Oligonucleotide targeting to alveolar macrophages by mannose receptor-mediated endocytosis, Biochim. Biophys. Acta, 1279 (1996) 227-234. 

FIGURE 14.1 Scanometric DNA array detection with enlarged nanoparticle probes. Use of oligonucleotide targets, labeled with gold nanoparticles, for recognizing DNA segments on a chip (reproduced from [13] with permission). 

William Fraser was born in Hamilton. He studied at the other of the two local universities, Strathclyde, where he obtained a first class B.Sc. honors degree in 1986 and Ph.D. in 1989 under the direction of Professor Colin J. Suckling and Professor Hamish C. S. Wood. He was awarded a Royal Society European Exchange Postdoctoral Fellowship and worked in the laboratories of Professor Albert Eschenmoser at the ETH, Zurich. In 1991, he took up his present position as lecturer in medicinal chemistry at Aston University, Birmingham. His scientific interests include nucleoside and nucleic acid chemistry, solid-supported, synthesis, and study of base-modified antigene oligonucleotides targeted to DNA. 

Oligonucleotide targeting to the kidney is more feasible than to many other tissues as a result of the glomerular filtration and tubular reabsorption of these poly-anionic agents. The effect is temporary allowing the therapy to be terminated when desired. Up until now, data has only been available on the kinetics and some renal and extra-renal effects of oligonucleotides in healthy animals. 

In the optimised experimental conditions the ply genosensor has been tested for different concentrations of the complementary oligonucleotide target. In the case of the enzymatic detection, a linear relationship between peak current and concentrations of complementary ply target has been obtained between 0.1 and 5 pg/pL, with a correlation coefficient of 0.9993, according to the following equation ... 

Mixed-backbone antisense oligonucleotides targeted to MDM2... 

Wang, H., Cai, Q., Zeng, X., Yu, D., Agrawal, S. and Zhang, R. (1999a) Anti-tumor activity and pharmacokinetics of a mixed-backbone antisense oligonucleotide targeted to RIa subunit of protein kinase A after oral administration. Proc. Natl. Acad. Sci. USA, 96, 13989-13994. 

Le Tinevez, R., Mishra, R.K. and Toulme, J.J. (1998) Selective inhibition of cell-free translation by oligonucleotides targeted to amRNA structure. Nucleic Acids Res., 26, 2273-2278. 

Read, M.L., Dash, P.R., Clark, A., Howard, K.A., Oupicky, D., Toncheva, V., Alpar, H.O., Schacht, E.H., Ulbrich, K. and Seymour, L.W. (2000) Physicochemical and biological characterization of an antisense oligonucleotide targeted against the bcl-2 mRNA complexed with cationic-hydrophilic copolymers. Eur. J. Pharm. Sci., 10, 169-177. 

Yu, R.Z., R.S. Geary, J.M. Leeds,T. Ushiro-Watanabe, M. Moore, J. Fitchett, J. Matson, T. Burckin, M.V. Templin, and A.A. Levin. 2001. Comparison of pharmacokinetics and tissue disposition of an antisense phosphorothioate oligonucleotide target-... 

J.A. Tami, and A.F. Dorr. 2002. Phase I trial of ISIS 104838, a 2 -methoxyethyl modified antisense oligonucleotide targeting tumor necrosis factor-alpha./. Pharmacol. Exp. Ther. 303 1334-1343. 

R. Crooke, N.M. Dean, and A.A. Levin. 2001. Pharmacokinetics and pharmacodynamics of an antisense phosphorothioate oligonucleotide targeting Fas mRNA in mice./. Pharmacol. Exp. Ther. 296 388-395. 

Sueda et al. (2000, 2002) reported a dual FRET probe assay, where two combinations, Eu-BHHCT-Cy 5 and Tb-BPTA-Cy 3, were tested for the donor-acceptor combination. They used a pair of 15-mer oligonucleotide probes to detect 31-34 synthetic oligonucleotide targets. As noted above, the emission intensities from Eu3+ and Tb3+ are negligibly weak at the Cy5 and Cy3 emission wavelengths (669 and 565 nm, respectively). Additionally, the initial emission intensities from Cy3 and Cy5 were quite weak when excited at the excitation wavelengths for the Eu3+ and Tb3+ chelates (340 and 325 nm, respectively). These properties enabled sensitive detection without quenchers. The detection limits were reported to be 200 pM and 30 pM for the Eu3+-Cy5 and Tb3+-Cy3 systems, respectively. 

Watanabe TA, Geary RS, Levin AA. Plasma protein binding of an antisense oligonucleotide targeting human icam-1 (ISIS 2302). Oligonucleotides 2006 16(2) 169-80. 

Massive and selective delivery of lipid-coated cationic lipoplexes of oligonucleotides targeted in vivo to hepatic endothelial cells, Pharm. Res., 19, 676-680. 

Figure 24.15. DNA Methylation. The structure of a DNA methylase bound to an oligonucleotide target shows that the base to be methylated is flipped out of the DNA helix into the active site of a SAM-dependent methylase.

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