目的:前列腺特异性膜抗原(prostate specific membrane antigen,PSMA)可作为前列腺癌诊断的重要靶点。该研究成功制备了1种新型68Ga标记PSMA小分子抑制剂PSMA11,并根据《中华人民共和国药典》标准进行质量控制,同时探讨该分子影像探针...目的:前列腺特异性膜抗原(prostate specific membrane antigen,PSMA)可作为前列腺癌诊断的重要靶点。该研究成功制备了1种新型68Ga标记PSMA小分子抑制剂PSMA11,并根据《中华人民共和国药典》标准进行质量控制,同时探讨该分子影像探针在前列腺癌动物模型中的靶向显像效果。方法:利用68Ge/68Ga发生器淋洗产生68Ga液,标记PSMA11制备正电子分子探针68Ga-PSMA11;建立符合药典标准的质量标准草案,对药品进行质量控制;利用小动物PET/CT,在人前列腺癌细胞LNCaP的SCID小鼠移植瘤模型上研究68Ga-PSMA11在注射后体内动态分布情况。结果:成功制备获得68GaPSMA11,质量控制符合规定,放射化学纯度大于99%,其在体内除肾脏及膀胱放射性生理性高分布外,在肿瘤部位有较明显特异性浓聚,其余器官组织放射性分布均处于较低水平。结论:68Ga-PSMA11标记方法简便,在体内肿瘤中特异性摄取程度高,是一个理想的正电子型PSMA特异性分子探针。展开更多
Introduction: 68Ga-PSMA-11 is considered the gold standard in detection of micro and oligometastases in advanced prostate cancer, being used for therapeutic planning, as well as, potentially, for evaluating response t...Introduction: 68Ga-PSMA-11 is considered the gold standard in detection of micro and oligometastases in advanced prostate cancer, being used for therapeutic planning, as well as, potentially, for evaluating response to treatment. The development of ready-to-use lyophilized kit of PSMA-11 adds quality and safety to the routine use of this radiopharmaceutical and represents a pharmacotechnical challenge as it must preserve the integrity and specificity of the ligand. Methods: PSMA-11 kit formulation was proposed, considering radiolabeling parameters and the preservation of the peptide during the lyophilization process, using mannitol as an excipient. Critical temperature characterization studies were carried out using DSC equipment and the freeze-drying process was developed. The direct radiolabeling conditions were evaluated and standardized using 68Ge/68Ga generator eluate from two different manufacturers (ITG and Eckert & Ziegler). The radiochemical purity was evaluated by TLC and HPLC. Biological evaluation was carried out with lyophilized PSMA-11 to demonstrate the integrity of the peptide and preservation of biological activity after the lyophilization process. Results: Based on critical temperature characterization studies, the freeze-drying cycle was designed to reach a freezing temperature of around −40˚C and primary drying at 2˚C. Using 20 mg of mannitol, an intact and elegant lyophilized cake was obtained. PSMA-11 lyophilized kit was directly labeled with 68Ga eluate from 68Ge/68Ga GMP generators (ITG and Eckert & Ziegler) resulting in % RP > 95% at pH 4.0 to 4.5. The results obtained from in vitro and in vivo biological competition studies confirmed the preservation of PSMA-11 affinity for the receptor after lyophilization. Conclusion: A lyophilized formulation (Kit) of PSMA-11 was successfully obtained, which preserved the integrity and biological activity of the peptide and guaranteed radiolabeling efficiency.展开更多
Radioiodine therapy, the most effective form of systemic radiotherapy available, is currently useful only for thyroid cancer because of the thyroid-specific expression of the human sodium iodide symporter （hNIS）. He...Radioiodine therapy, the most effective form of systemic radiotherapy available, is currently useful only for thyroid cancer because of the thyroid-specific expression of the human sodium iodide symporter （hNIS）. Here, we explore the efficacy of a novel form of gene therapy using prostate-specific membrane antigen （PSMA） promoter-mediated hNIS gene transfer followed by radioiodine administration for the treatment of castration-resistant prostate cancer （CRPC）. The androgen-dependent C33 LNCaP cell line and the androgen-independent C81 LNCaP cell line were transfected by adenovirus. PSMA promoter-hNIS （Ad.PSMApro-hNIS） or adenovirus.cytomegalovirus-hNIS containing the cytomegalovirus promoter （Ad.CMM-hNIS） or a control virus. The iodide uptake was measured in vitro. The in vivo iodide uptake by C81 cell xenografts in nude mice injected with an adenovirus carrying the hNIS gene linked to PSMA and the corresponding tumor volume fluctuation were assessed. Iodide accumulation was shown in different LNCaP cell lines after Ad.PSMApro-hNIS and Ad.CMV-hNIS infection, but not in different LNCaP cell lines after adenovirus.cytomegalovirus （Ad.CMV） infection. At each time point, higher iodide uptake was shown in the C81 cells infected with Ad.PSMApro-hNIS than in the C33 cells （P 〈 0.05）. An in vivo animal model showed a significant difference in 1311 radioiodine uptake in the tumors infected with Ad.PSMApro-hNIS, Ad.CMV-hNIS and control virus （P 〈 0.05） and a maximum reduction of tumor volume in mice infected with Ad.PSMApro-hNIS. These results show prostate-specific expression of the hNIS gene delivered by the PSMA promoter and effective radioiodine therapy of CRPC by the PSMA promoter-driven hNIS transfection.展开更多
文摘目的:前列腺特异性膜抗原(prostate specific membrane antigen,PSMA)可作为前列腺癌诊断的重要靶点。该研究成功制备了1种新型68Ga标记PSMA小分子抑制剂PSMA11,并根据《中华人民共和国药典》标准进行质量控制,同时探讨该分子影像探针在前列腺癌动物模型中的靶向显像效果。方法:利用68Ge/68Ga发生器淋洗产生68Ga液,标记PSMA11制备正电子分子探针68Ga-PSMA11;建立符合药典标准的质量标准草案,对药品进行质量控制;利用小动物PET/CT,在人前列腺癌细胞LNCaP的SCID小鼠移植瘤模型上研究68Ga-PSMA11在注射后体内动态分布情况。结果:成功制备获得68GaPSMA11,质量控制符合规定,放射化学纯度大于99%,其在体内除肾脏及膀胱放射性生理性高分布外,在肿瘤部位有较明显特异性浓聚,其余器官组织放射性分布均处于较低水平。结论:68Ga-PSMA11标记方法简便,在体内肿瘤中特异性摄取程度高,是一个理想的正电子型PSMA特异性分子探针。
文摘Introduction: 68Ga-PSMA-11 is considered the gold standard in detection of micro and oligometastases in advanced prostate cancer, being used for therapeutic planning, as well as, potentially, for evaluating response to treatment. The development of ready-to-use lyophilized kit of PSMA-11 adds quality and safety to the routine use of this radiopharmaceutical and represents a pharmacotechnical challenge as it must preserve the integrity and specificity of the ligand. Methods: PSMA-11 kit formulation was proposed, considering radiolabeling parameters and the preservation of the peptide during the lyophilization process, using mannitol as an excipient. Critical temperature characterization studies were carried out using DSC equipment and the freeze-drying process was developed. The direct radiolabeling conditions were evaluated and standardized using 68Ge/68Ga generator eluate from two different manufacturers (ITG and Eckert & Ziegler). The radiochemical purity was evaluated by TLC and HPLC. Biological evaluation was carried out with lyophilized PSMA-11 to demonstrate the integrity of the peptide and preservation of biological activity after the lyophilization process. Results: Based on critical temperature characterization studies, the freeze-drying cycle was designed to reach a freezing temperature of around −40˚C and primary drying at 2˚C. Using 20 mg of mannitol, an intact and elegant lyophilized cake was obtained. PSMA-11 lyophilized kit was directly labeled with 68Ga eluate from 68Ge/68Ga GMP generators (ITG and Eckert & Ziegler) resulting in % RP > 95% at pH 4.0 to 4.5. The results obtained from in vitro and in vivo biological competition studies confirmed the preservation of PSMA-11 affinity for the receptor after lyophilization. Conclusion: A lyophilized formulation (Kit) of PSMA-11 was successfully obtained, which preserved the integrity and biological activity of the peptide and guaranteed radiolabeling efficiency.
文摘Radioiodine therapy, the most effective form of systemic radiotherapy available, is currently useful only for thyroid cancer because of the thyroid-specific expression of the human sodium iodide symporter （hNIS）. Here, we explore the efficacy of a novel form of gene therapy using prostate-specific membrane antigen （PSMA） promoter-mediated hNIS gene transfer followed by radioiodine administration for the treatment of castration-resistant prostate cancer （CRPC）. The androgen-dependent C33 LNCaP cell line and the androgen-independent C81 LNCaP cell line were transfected by adenovirus. PSMA promoter-hNIS （Ad.PSMApro-hNIS） or adenovirus.cytomegalovirus-hNIS containing the cytomegalovirus promoter （Ad.CMM-hNIS） or a control virus. The iodide uptake was measured in vitro. The in vivo iodide uptake by C81 cell xenografts in nude mice injected with an adenovirus carrying the hNIS gene linked to PSMA and the corresponding tumor volume fluctuation were assessed. Iodide accumulation was shown in different LNCaP cell lines after Ad.PSMApro-hNIS and Ad.CMV-hNIS infection, but not in different LNCaP cell lines after adenovirus.cytomegalovirus （Ad.CMV） infection. At each time point, higher iodide uptake was shown in the C81 cells infected with Ad.PSMApro-hNIS than in the C33 cells （P 〈 0.05）. An in vivo animal model showed a significant difference in 1311 radioiodine uptake in the tumors infected with Ad.PSMApro-hNIS, Ad.CMV-hNIS and control virus （P 〈 0.05） and a maximum reduction of tumor volume in mice infected with Ad.PSMApro-hNIS. These results show prostate-specific expression of the hNIS gene delivered by the PSMA promoter and effective radioiodine therapy of CRPC by the PSMA promoter-driven hNIS transfection.
