CAJ | 학술논문

目的制备99Tcm标记的survivin mRNA反义肽核酸(PNA)探针,并进行荷瘤裸鼠体内基因显像,研究其对肿瘤早期诊断的价值.方法化学合成survivin mRNA的反义、无义PNA,在5＇端连上4个氨基酸[ Gly- (D) Ala-Gly-Gly],形成1个类似N4结构的强螯合基团；为消除空间阻碍,引入1个γ-氨基丁酸(Aba)作为隔离物,利用配体交换法进行99Tcm标记.用HPLC及ITLC对标记物的标记率、放化纯进行鉴定.并对反义、无义组各5只人肺癌A549荷瘤裸鼠行99Tcm-survivin mRNA反义、无义PNA体内显像.注药后1,2和4h分别显像,利用ROI测得肿瘤与对侧组织的T/NT比值.结果分析采用SPSS 13.0软件进行成组t检验.结果 99Tcm-survivin mRNA反义PNA即刻标记率为(95.48±1.92)％,放化纯＞95％,且标记物体外稳定性好,与血清保温24h后标记率仍＞85％.无义PNA标记率与之基本一致.99Tcm-survivin mRNA反义PNA在肿瘤组织内特异性浓聚,随时间延长,浓聚程度逐渐增加,1,2和4 h T/NT值分别为2.70±0.28,3.44±0.35和4.21±0.63.无义PNA在肿瘤组织中稍有浓聚,但在4h内变化不大,4h时T/NT值(3.12±0.50)与反义组差异有统计学意义(t =2.918,P=0.019).结论 99Tcm-survivin mRNA反义PNA即刻标记率高,稳定性好,无需纯化即可用于显像,在肿瘤组织中特异性浓聚,对肿瘤的早期诊断有潜在价值.
목적 제비99Tcm표기적survivin mRNA반의태핵산(PNA)탐침,병진행하류라서체내기인현상,연구기대종류조기진단적개치.방법 화학합성survivin mRNA적반의、무의PNA,재5＇단련상4개안기산[ Gly- (D) Ala-Gly-Gly],형성1개유사N4결구적강오합기단；위소제공간조애,인입1개γ-안기정산(Aba)작위격리물,이용배체교환법진행99Tcm표기.용HPLC급ITLC대표기물적표기솔、방화순진행감정.병대반의、무의조각5지인폐암A549하류라서행99Tcm-survivin mRNA반의、무의PNA체내현상.주약후1,2화4h분별현상,이용ROI측득종류여대측조직적T/NT비치.결과분석채용SPSS 13.0연건진행성조t검험.결과 99Tcm-survivin mRNA반의PNA즉각표기솔위(95.48±1.92)％,방화순＞95％,차표기물체외은정성호,여혈청보온24h후표기솔잉＞85％.무의PNA표기솔여지기본일치.99Tcm-survivin mRNA반의PNA재종류조직내특이성농취,수시간연장,농취정도축점증가,1,2화4 h T/NT치분별위2.70±0.28,3.44±0.35화4.21±0.63.무의PNA재종류조직중초유농취,단재4h내변화불대,4h시T/NT치(3.12±0.50)여반의조차이유통계학의의(t =2.918,P=0.019).결론 99Tcm-survivin mRNA반의PNA즉각표기솔고,은정성호,무수순화즉가용우현상,재종류조직중특이성농취,대종류적조기진단유잠재개치.
Objective To prepare the 99Tcm-survivin mRNA antisense peptide nucleic acid (PNA)and investigate its value as a gene imaging agent in tumor bearing mice and early diagnosis in tumor.Methods Survivin mRNA antisense PNA and mismatch PNA were synthesized.Four amino acids (Gly- (D)Ala-Gly-Gly) and Aba (4-aminobutyric acid) were linked to the 5' end of PNA.Gly- (D)Ala-Gly-Gly served as a chelating moiety for strong chelation of 99Tcm and Aba acted as a spacer to minimize the steric hindrance.PNAs were labeled with 99Tcm by the ligand-exchange method.The labeling efficiency and radiochemical purity were measured by HPLC and ITLC methods.There were five BALB/c nude mice bearing human lung carcinoma ( A549 ) in each of antisense PNA and mismatch PNA groups.Gene imaging of 99Tcm-survivin mRNA antisense and mismatch PNAs were performed at 1,2 and 4 h post the injection,respectively,and the T/NT ratio was measured by the method of ROI.The statistical comparisons of average values were performed with the two-group t-test for independent sample by SPSS 13.0.Results The product kept stable in vitro.The labeling efficiency of 99Tcm-survivin mRNA antisense PNA was (95.48 ±1.92)％ and more than 85％ after the incubation for24 h in serum.The radiochemical purity was ＞ 95％.The labeling efficiency of mismatch PNA was similar to the antisense PNA.99Tcm-survivin mRNA antisense PNA was especially uptaken by tumor lesion,and its accumulation reached the top at 4 h post the injection.T/NT ratios at 1,2,and 4 h were 2.70 ± 0.28,3.44 ± 0.35,4.21 ± 0.63,respectively.In the comparison,the T/NT ratio of 99Tcm-survivin mRNA mismatch PNA at 4 h (3.12 ±0.50) was significantly lower (t =2.918,P =0.019).Conclusions 99Tcm-survivin mRNA antisense PNA has high labeling efficiency,good stability and no need of purification.Its characteristic of especial uptake by tumor lesion provides the potential value in early diagnosis of tumor.