유전자 영상용 HSV1-TK 기질의 합성

안순혁(Soon Hyuk Ahn),최창운(Chang Woon Choi),임상무(Sang Moo Lim),오옥두(Ok Doo Awh),최태현(Tae Hyun Choi) 대한핵의학회 2002 핵의학 분자영상 Vol.36 No.2

목적: 유전자 치료에서, 종양세포에 herpes simplex virus thymidine kinase 유전자를 발현시키고 이에 민감한 prodrug을 전신투여하여 발현된 종양세포에 특이적으로 집적되는 방법은 매우 효육적인 바업이다. 대표적인 prodrug인, IVDU, IVFRU는 herpes simplex virus type 1의 비침습적 영상화 방법에 응용되는 방사옥소 표지가능 화합물이다. 재료 및 방법: Trans-1-trimethylsilyl-2-tri-n-butylstannylethylene과 uridine 변형체상의 iodo-uracil을 Pd촉매하에서 반응시켜 표지전구체인 5-trimethylvinyl-deoxy-uridine과 5-trimethylsilylvinyl-deoxy-fluororibofuranosyl uracil을 합성하였다. 이것을 column chromatography의 방법으로 분리 정제하였다. 합성한 각 전구체를 ICl 담체를 이용하여 높은 수율로 표지하였고, HPLC를 사용하여 분리하였다. Radiohalogen exchange 방법은 비방사능을 낮게 할수록 표지에 효율적으로 알려져 있다. 이 방법으로 ICl 방법을 사용하여 담체를 포함하는 높은 방사능의 화합물을 얻을 수 있다. 결과: IVDU와 IVFRU 표지를 위한 전구체 합성수율은 각각 43, 72% 였다. ICl로 담체를 이용한 표지방법을 사용하여 IVDU와 IVFRU 표지수율은 98% 이상이었다. 결론: HSV1-tk를 이용한 유전자 영상용 기질의 전구체를 성공적으로 합성하였고, 95% 이상의 높은 표지수율의 유전자 영상용 방사성 추적자를 성공적으로 제조하였다. Purpose: In gene therapy, tumor cells expressing the herpes simplex virus thymidine kinase are sensitive to prodrugs. Potential prodrugs IVDU and IVFRU were synthesized and radiolabeled with radiodine for noninvasive imaging of herpes simplex virus type 1 gene expression. Material and Methods: 5-(2-trimethysilyl)vinyl-2`-deoxyuridine and 5-t(2-trimethylsilyl-2`-fluoro-2`-deoxyuridine, precursors of 5-(2-iodo)viny 1-2`-deoxy uridine(IVDU) and 5-(2-iodo)-2`-vinyl-2`-deoxy-2`-fluororibofuranosyl uracil(IVFRU), were synthesized from reaction of trans-1-trimethylsillyl-2-tri-n-butylstannylethylene with 5-iodo-2`-deoxyuridine and 5-iodo-2`-fluoro-2`-deoxyuridine, respectively, on the condition of Pd catalyst. These precursors were separated from reaction mixture by silica gel column chromatography method. Each precursor was radioiodinated with radioiodine by mixing with ICl oxidizing agent. These radioiodinated compounds were purified with HPKC. Radiohalogen exchange has been shown to be effective for the synthesis of products with lower specific activity. Similarly, carrier-added and high specific activity products have been isolated in respectable radiochemical yields using ICl method. Results: Synthetic yield of precursors, IVDU and IVFRU were 43% and 18%, respectively. Radiochemical purity of both compunds was over 98%. Conclusion: We synthesized precursors of IVDU and IVFRU for monitoring of HSV1-tk gene expression. Radiotracers were radioiodinated with high radiolabeling yield by ICl method. (Korean J Nucl Med 2002;36;102-109)

종양 이식 백서에서 3-<131I>iodo-O-methyl-L-alpha-methyltyrosine 의 체내 동태 연구 - L-3-<131I>iodo-alpha-methyltyrosine 와 비교

최창운,양승대,우광선,정위섭,임수정,서용섭,전권수,안순혁,이종두,홍성운,임상무 ( Chang Woon Choi,Seung Dae Yang,Kwang Sun Woo,Wee Sup Chung,Soo Jung Lim,Yong Sup Suh,Kwon Soo Chun,Soon Hyuk Ahn,Jong Doo Lee,Sung Soon Hong,Sang Moo Lim 대한핵의학회 1998 핵의학 분자영상 Vol.32 No.3

Purpose : The aim of this sutdy was to evaluate the feasibility of 3-[131I]Iodo-O-methyl-L-a-methyltyrosine ([131I]OMINT) as an agent for tumor image. Materlals and Methods: After synthesis of 4-O-methyl-L-a-methyltyrosine (OMAMT), OMAMT was labeled with 131I using Iodogen method. In viro cellular uptake study was performed using 9 L gliosarcoma cells at various time points upto 4 hr. The biodistribution (five rats implanted with the 9 L gliosarcoma cells per group) was evaluated at 30 min, 2 hr, 24 hr after iv injection of 3.7 MBq [131I]OMIMT or L-3-[131I]iodo-a-methyltyrosine ([131I]IMT). Gamma camera images were obtained at 30min, 2 hr, and 24 hr. Results : [131I]OMINT uptake was 3.3 times and 2.5 times higher than [131I]IMT uptake at 30 min and 60 min, respectively and same after 2 hr in in vitro sutdy using 9L gliosarcoma cells. Maximum accumulation in tumor occurred at 30 min for both [131IOMINT and [131I]IMT in tumor bearing rats. The tumor uptake of [131I]OMINT was significantly higher than that of [131I]IMT in tumor bearing rats. The tumor uptake of [131I]OMIMT was significantly higher than that of [131I]IMT at early time point studied (3.74 +- 0.48 vs 0.38 +- 0.17% ID/g at 30 min and 2.40 +- 0.17 vs 0.24 +- 0.03% ID/g at 2 hr, respectively, p<0.01). However, the tumor uptake of both radiolabels were not significantly different at 24 hr (0.04 +- 0.01 vs 0.05 +- 0.01% ID/g). Tumor was visualized as early as at 30 min in gamma camera images. Conclusion : These data suggested that [131I]OMIMT might be a useful tumor imaging agent and has more advantage for the tumor imaging compared to [131I]IMT. (korean J NuclMed 1998;32;290-7)

체내 안정형 HSV1-tk (Herpes Simplex Virus Type-1 Thymidine Kinase) 영상용 IVDU 유도체의 합성

김은정 ( Eun Jung Kim ),최태현 ( Tae Hyun Choi ),안순혁 ( Soon Hyuk Ahn ),김병수 ( Byoung Soo Kim ),박현 ( Hyun Park ),천기정 ( Gi Jeong Cheon ),이학준 ( Hak June Rhee ),안광일 ( Gwang Il An ) 대한핵의학회 2009 핵의학 분자영상 Vol.43 No.5

목적: 화합물이 가지는 항바이러스 및 항암 작용으로 인하여 5-iododeoxyuridine 유도체들에 관한 연구는 매우 광범위하게 이루어져왔다. 방사 요오드가 치환된 이들 화합물에 대한 연구의 주요 목표는 체내 및 체외 평가 시 효과적 일뿐만 아니라, 보다 안정한 화합물을 개발하는 것이다. 본 연구를 통해, 다양한 방사성의약품의 중간체로도 이용되어질 수 있는 carbocyclic radioiododeoxyuridineanalogue (ddIVDU)를 합성하여 생물학적 평가를 수행하고자 하였다. 대상 및 방법: 목표 화합물의 합성은 Pd(0)-촉매 결합반응, LAH 환원반응, hetero Diels-Alder 반응을 주요 반응으로 하여 수행하였다(Sch 3). 합성된 화합물의 생물학적 평가를 위해 MCA와 MCA-tk 세포에 다양한 농도의 GCV와 carbocyclic ddIVDU를 처리하여 MTS 법을 이용해 세포독성을 보았고, [125I]carbocyclic ddIVDU를 이용해 MCA와 MCA-tk 세포에서 HSV1-tk에 의한 선택적 섭취를 비교 평가 하였다. 결과: Carbocyclic ddIVDU 및 요오드 도입을 위한 전구물질의 합성을 cyclopentadiene을 출발물질로 하여 높은 수율에 의해 수행하였다. 방사요오드를 이용한 동위원소 도입 반응은 각각, 80% 이상의 방사표지 수율 및 95% 이상의 방사 화학적 순도를 나타내었다. 세포독성 결과 MCA-tk 세포에서 carbocyclic ddIVDU는 GCV에 비해 세포독성이 작았고, MCA에서는 유사한 세포독성을 보였다. [125I]carbocyclic ddIVDU는 MCA-tk 세포에서 uptake는 8시간째까지 계속 증가하는 양상을 보였으며, MCA 세포에서 uptake는 4시간째까지 일정하게 유지되다가 8시간째 급격히 증가하였다. [125I]carbocyclic ddIVDU의 uptake는 MCA보다 MCA-tk에서 약 2-5배 정도 높은 결과를 보였다. 결론: 진행되어진 생물학적 결과로부터 이 유도체는 체내 평가 시 매우 안정할 뿐만 아니라, GCV에 비해 독성이 덜하고, HSV1-tk cell에 선택적임을 보여준다. 따라서 신규 화합물인 carbocyclic ddIVDU는 HSV1-tk를 영상화하는데 유용하게 이용되어질 수 있을 것이다. Purpose: 5-iododeoxyuridine analogues have been exclusively developed for the potential antiviral and antitumor therapeutic agents. In this study, we synthesized carbocyclic radioiododeoxyuridineanalogue (ddIVDU) and carbocyclic intermediate as efficient carbocyclic radiopharmaceuticals. Materials and Methods: The synthesis is LAH reduction, hetero Diels-Alder reaction as key reactions including Pd(0)-catalyzed coupling reaction together with organotin. MCA-RH7777 (MCA) and MCA-tk (HSV1-tk positive) cells were treated with various concentration of carbocyclic ddIVDU, and GCV. Cytotoxicity was measured by the MTS methods. For in vitro uptake study, MCA and MCA-tk cells were incubated with 1uCi of [125I]carbocyclic ddIVDU. Accumulated radioactivity was measured after various incubation times. Results: The synthesis of ddIVDU and precursor for radioiodination were achieved from cyclopentadiene in good overall yield, respectively. The radioiododemetallation for radiolabeling gave more than 80% yield with >95% radiochemical purity. GCV was more toxic than carbocyclic ddIVDU in MCA-tk cells. Accumulation of [125I]carbocyclic ddIVDU was higher in MCA-tk cells than MCA cells. Conclusion: Biological data reveal that ddIVDU is stable in vitro, less toxic than ganciclovir (GCV), and selective in HSV1-tk expressed cells. Thus, this new carbocyclic nucleoside, referred to in this paper as carbocyclic 2`,3`-didehydro-2`,3`-dideoxy-5- iodovinyluridine (carbocyclic ddIVDU), is a potential imaging probe for HSV1-tk. (Nucl Med Mol Imaging 2009;43(5):478-486)

폴라로그래피를 이용한 [201Tl]염화탈륨 주사액의 중금속 분석

이동훈,전권수,유국현,김상욱,임상무,서용섭,양승대,안순혁,최강혁 대한핵의학회 2000 핵의학 분자영상 Vol.34 No.4

Purpose: Thallous-201 chloride produced at Korea Cancer Center Hospital(KCCH) is used in detecting cardiovascular disease and cancer. Thallium impurity can cause emesis, catharsis and nausea, so the presence of thallium and other metal impurities should be determined. According to USP and KP, their amounts must be less than 2 ppm in thallium and 5 ppm in total. In this study, the detection method of trace amounts of metal impurities in [201Tl]TlCl injection with polarography was optimized without environmental contamination. Materials and Methods: For the detection of metal impurities, Osteryoung Square Wave Stripping Voltammetry method was used in Bio-Analytical System (BAS) 50W polarograph. The voltammetry was composed of Dropping Mercury Electrode (DME) as a working electrode, Ag/AgCl as a reference electrode and Pt wire as a counter electrode. Square wave stripping method, which makes use of formation and deformation of amalgam, was adopted to determine the metal impurities, and pH 7 phosphate buffer was used as supporting electrolyte. Results: T1, Cu and Pb in thallous-201 chloride solution were detected by scanning from 300 mV to -800 mV. Calibration curves were made by using TlNO3, CuSO4 and Pb(NO3)2 as standard solutions. Tl was confirmed at -450 mV peak potential and Cu at -50 mV. Less than 2 ppm of Tl and Cu was detected and Pb was not detected in KCCH-produced thallous-201 chloride injection. Conclusion: Detection limit of thallium and copper is approximately 50 ppb with this method. As a result of this experiment, thallium and other metal impurities in thallous-201 chloride injection, produced at Korea Cancer Center Hospital, are in the regulation of USP and KP. Polarograph could be applied for the determination of metal impurities in the quality control of radiopharmaceuticals conveniently without environmental contamination. (Korean J Nucl Med 2000;34:336-43)

C -11 및 F - 18 표지 콜린의 합성과 체내동태에 관한 연구

전권수,유국현,김상욱,임상무,홍성운,서용섭,양승대,안순혁,허민구 대한핵의학회 2001 핵의학 분자영상 Vol.35 No.3

Objectives: Recently, [methyl-(11)^C]-(β-Hydroxyethyl)trimethylammonium ([(11)^C]choline) has been discovered to be a very effective tracer in imaging various human tumors using positron emission tomography. Because of the short half-life of C-11, it is very difficult to use in a routine imaging procedure and needs a frequent synthesis of [(11)^]choline. This can be supplemented by the substitution of [(11)^Ccholine with [methyS-18]fluorocholine. Here, we would like to report cell uptake and biodistribution of [(11)^Ccholine and [(18)^F]fluorocholine as a basic study. Methods [(11)^C]Choline was prepared by the treatment of [(11)^C]CHzI with N,N-dimethylaminoethanol and [18F]fluorocholine was synthesized from reaction of CHzBr[18F]F with N,N-dimethylaminoethanol. The radiochemical purity was checked by high performance liquid chromatography (HPLC). The biodistribution of [(11)^C]choline and [(18)^F]fluorocholine was determined in balb/c mouse at 5 min, 20 min, 40 min and 80 min. The cell uptake wa measured using glioma (9L) and colon adeocarcinoma (SW620). Results: The radiochemical purity was more than 98% after purification. In the liver, uptake did not change over time the uptake was 20/ID/g for [C]choline and 13%ID/g for [(18)^F]fluorocholine. In the kidney, radioactivity decreased over tirne the uptake was 15%1D/g for [(11)^Ccholine and 20%ID/g for [(18)^F]fluorocholine, 80 min post-injection. The cell uptake of [(11)^Ccholine was 4.93% for glioma (9L) and 18.69F for colon adenocarcinoma (SW620). For [(18)^F]fluorocholine, 1.77% for glioma (9L) and 2.77% for colon adenocarcinoma (SW620). Conclusion: [(11)^CCholine and [(18)^F]fluorocholine showed a different cell uptake tendency, depending on cancer cell line. (Korean J Nucl Med 200135:185-191)