用于癌症非侵入性磁共振成像的新型聚二氨基丙酸酯树枝状大分子PNA-肽嵌合体的合成。

Synthesis of novel polydiamidopropanoate dendrimer PNA-peptide chimeras for non-invasive magnetic resonance imaging of cancer.

作者信息

Amirkhanov N V, Wickstrom Eric

机构信息

Department of Biochemistry and Molecular Pharmacology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.

出版信息

Nucleosides Nucleotides Nucleic Acids. 2005;24(5-7):423-6. doi: 10.1081/ncn-200059955.

DOI:10.1081/ncn-200059955

PMID:16247963

Abstract

A variety of dendrimers can be conjugated to oligonucleotides to increase the number of contrast paramagnetic atoms (e.g., gadolinium or dysprosium) per probe. Thus, it was of interest to test a route for assembly of chelating dendrimer branches directly on the N-termini of peptide nucleic acid (PNA)-peptide chimeras by continuous solid-phase coupling on polymer supports. Dendrimer-PNA-peptides complementary to 12 nt of mutant KRAS mRNA have been prepared with a C-terminal insulin-like growth factor 1 (IGF1) analog d(Cys-Ser-Lys-Cys) and N-terminal polydiamidopropanoate (PDAP) dendrimers with different numbers of diaminopropanoate residues. 1,4, 7, 10-Tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelating moieties were then coupled to PDAP dendrimer-PNA-peptide chimeras before cleavage from the polymer supports. The DOTA-PDAP-PNA-peptide probes with 1, 2, 4, 8, or 16 amino (or DOTA) moieties were cleaved, purified by RP-HPLC, and characterized by MALDI-TOF mass spectroscopy.

摘要

多种树枝状聚合物可与寡核苷酸缀合，以增加每个探针中顺磁性对比原子（如钆或镝）的数量。因此，通过在聚合物载体上进行连续固相偶联，直接在肽核酸（PNA）-肽嵌合体的N端组装螯合树枝状聚合物分支的途径是值得研究的。已制备出与12个核苷酸的突变型KRAS mRNA互补的树枝状聚合物-PNA-肽，其C端为胰岛素样生长因子1（IGF1）类似物d（Cys-Ser-Lys-Cys），N端为具有不同数量二氨基丙酸酯残基的聚二氨基丙酸酯（PDAP）树枝状聚合物。然后，在从聚合物载体上切割下来之前，将1,4,7,10-四氮杂环十二烷-1,4,7,10-四乙酸（DOTA）螯合部分偶联到PDAP树枝状聚合物-PNA-肽嵌合体上。将具有1、2、4、8或16个氨基（或DOTA）部分的DOTA-PDAP-PNA-肽探针切割下来，通过反相高效液相色谱（RP-HPLC）纯化，并通过基质辅助激光解吸电离飞行时间质谱（MALDI-TOF）进行表征。