Small peptide-based compounds have attracted an enormous interest as carrier molecules to selectively de- liver radionuclides to target tissues, sparing critical normal organs. When looking for "matched pairs&quo...Small peptide-based compounds have attracted an enormous interest as carrier molecules to selectively de- liver radionuclides to target tissues, sparing critical normal organs. When looking for "matched pairs" of radionuclides, suitable for radiolabeling of peptides for diagnosis and therapy, technetium and rhenium represent an almost ideal constellation. The important role of technetium-99m and Re-186/188 is based on the decay characteristics, suitable for tumor diagnosis and therapy. Tc-99m and Re-188 are readily available by either a 99Mo/99mTc or the 188W/188Re ra- dionuclide generator system. Furthermore, technetium and rhenium are chemically related and share structural as well as reactive similarities, which prompt an attractive "matched-pair" situation. This article shows an overview of 99mTc- and 186/188Re-radiolabeled peptides that have been tested for their potential use as imaging and therapeutic agents in oncological diseases.展开更多
To explore the preparation method of liposome-coated 99mTc-labeled antisense oligonucleotide (ASON), targeteing the proliferating cell nuclear antigen (PCNA), and to explore the biological characteristics and the upta...To explore the preparation method of liposome-coated 99mTc-labeled antisense oligonucleotide (ASON), targeteing the proliferating cell nuclear antigen (PCNA), and to explore the biological characteristics and the uptake kinetics of a radiolabeled probe in vascular smooth muscle cells, an 18-base single-stranded antisense oligonucleotide targeting PCNA mRNA and the complementary strand (sense oligonucleotide, SON) were synthesized. The ASON (SON) was labeled with 99mTc, by conjugating the bifunctional chelator (hydrazino nicotinamide, HYNIC), and puri- fied through a gel filtration column of Sephadex G-25. The product was then encapsulated in cationic liposome (oli- gofectamineTM). The radiolabeling efficiency, radiochemical purity, stability of the liposome-coated 99mTc-HYNIC- ASON in a phosphate buffered solution (PBS), and fresh human serum and its uptake rate were studied. There was no significant difference between the 99mTc radiolabeling efficiencies of HYNIC-ASON and HYNIC-SON, which were 60.04% ± 1.92% and 59.60% ± 2.53%, respectively (P > 0.05, n = 5). The radiochemical purity of the lipo- some-coated 99mTc-HYNIC-ASON was 94.70% ± 1.90% (n = 5). And after incubation with PBS and fresh human se- rum at a concentration of 1.2 μg·mL-1 for 120 min, the radiochemical purities were 92.27% and 91.55% respectively. At 90 min after transfection, the uptake rate of the liposome-coated 99mTc-HYNIC-ASON reached its peak of 83.8% ± 5.92% in vascular smooth muscle cells (VSMCs) and was much higher than that of the nonliposome-coated 99mTc- HYNIC-ASON, which was 11.16% ± 0.54% (P < 0.01, n = 4). The labeling method of PCNA ASON (SON) conju- gated by HYNIC has been proved successful. The liposome was able to enhance the ASON (SON) uptake in VSMCs, and could be widely used as a safe, convenient, effective gene transfer carrier.展开更多
文摘Small peptide-based compounds have attracted an enormous interest as carrier molecules to selectively de- liver radionuclides to target tissues, sparing critical normal organs. When looking for "matched pairs" of radionuclides, suitable for radiolabeling of peptides for diagnosis and therapy, technetium and rhenium represent an almost ideal constellation. The important role of technetium-99m and Re-186/188 is based on the decay characteristics, suitable for tumor diagnosis and therapy. Tc-99m and Re-188 are readily available by either a 99Mo/99mTc or the 188W/188Re ra- dionuclide generator system. Furthermore, technetium and rhenium are chemically related and share structural as well as reactive similarities, which prompt an attractive "matched-pair" situation. This article shows an overview of 99mTc- and 186/188Re-radiolabeled peptides that have been tested for their potential use as imaging and therapeutic agents in oncological diseases.
基金Supported by Natural Science Foundation of China (No.30271439)
文摘To explore the preparation method of liposome-coated 99mTc-labeled antisense oligonucleotide (ASON), targeteing the proliferating cell nuclear antigen (PCNA), and to explore the biological characteristics and the uptake kinetics of a radiolabeled probe in vascular smooth muscle cells, an 18-base single-stranded antisense oligonucleotide targeting PCNA mRNA and the complementary strand (sense oligonucleotide, SON) were synthesized. The ASON (SON) was labeled with 99mTc, by conjugating the bifunctional chelator (hydrazino nicotinamide, HYNIC), and puri- fied through a gel filtration column of Sephadex G-25. The product was then encapsulated in cationic liposome (oli- gofectamineTM). The radiolabeling efficiency, radiochemical purity, stability of the liposome-coated 99mTc-HYNIC- ASON in a phosphate buffered solution (PBS), and fresh human serum and its uptake rate were studied. There was no significant difference between the 99mTc radiolabeling efficiencies of HYNIC-ASON and HYNIC-SON, which were 60.04% ± 1.92% and 59.60% ± 2.53%, respectively (P > 0.05, n = 5). The radiochemical purity of the lipo- some-coated 99mTc-HYNIC-ASON was 94.70% ± 1.90% (n = 5). And after incubation with PBS and fresh human se- rum at a concentration of 1.2 μg·mL-1 for 120 min, the radiochemical purities were 92.27% and 91.55% respectively. At 90 min after transfection, the uptake rate of the liposome-coated 99mTc-HYNIC-ASON reached its peak of 83.8% ± 5.92% in vascular smooth muscle cells (VSMCs) and was much higher than that of the nonliposome-coated 99mTc- HYNIC-ASON, which was 11.16% ± 0.54% (P < 0.01, n = 4). The labeling method of PCNA ASON (SON) conju- gated by HYNIC has been proved successful. The liposome was able to enhance the ASON (SON) uptake in VSMCs, and could be widely used as a safe, convenient, effective gene transfer carrier.
