| Autor: |
Lewis, M. R., Jia, F., Gallazzi, F., Wang, Y., Zhang, J., Shenoy, N., Lever, S. Z., Hannink, M. |
| Zdroj: |
Bioconjugate Chemistry; November 2002, Vol. 13 Issue: 6 p1176-1180, 5p |
| Abstrakt: |
A new antisense peptide−peptide nucleic acid (peptide−PNA) conjugate, designed for targeting bcl-2 expression, has been radiolabeled, characterized, and evaluated for bcl-2 mRNA binding in a cell-free system. A PNA complementary to the first six codons of the bcl-2 gene was synthesized by standard solid-phase Fmoc chemistry and conjugated to a new derivative of 1,4,7,10-tetraazacyclododecane-N,N,N ,N -tetraacetic acid (DOTA) that allows macrocyclic radiometal chelates to be incorporated into any sequence position of a peptide−PNA conjugate. The DOTA−PNA conjugate was then coupled to a membrane-permeating transduction peptide, PTD-4, designed for intracellular delivery of the radiolabeled PNA. The conjugate was characterized by HPLC and ESI-MS and labeled with 111In and 90Y to high specific activities (>1000 Ci/mmol) with high radiochemical purity. Northern blot analysis showed that 90Y-PTD-4−K(DOTA)−anti-bcl-2-PNA bound specifically to as little as 50 fmol of bcl-2 mRNA, a result equivalent to that obtained with the analogous 32P-labeled DNA antisense oligonucleotide. Thus, the mRNA targeting properties of 111In- and 90Y-PTD-4−K(DOTA)−anti-bcl-2-PNA demonstrate potential for diagnostic imaging and targeted radiotherapy applications in bcl-2-positive cancers. |
| Databáze: |
Supplemental Index |
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