中文摘要：

目的利用细菌鞭毛肽库技术筛选与高转移潜能的前列腺癌PC-3M-1E8细胞特异结合的多肽片段。方法利用细菌鞭毛肽库对人前列腺癌高低转移配对细胞株PC-3M-1E8和PC-3M-2B4进行筛选,获得与前列腺癌高转移细胞亲和的细菌克隆。将结合能力最强细菌克隆所共同拥有的重复多肽序列挑选出来并化学合成;利用荧光染色和流式细胞仪,通过细胞亲和、竞争拮抗实验及荷瘤小鼠模型,鉴定合成肽与前列腺癌高转移细胞的体内外的结合特异性。结果筛选出一段核心序列为NVVRQ的五肽,命名为TMTP1;FITC-TMTP1可特异地与PC-3M-1E8高度亲和,且这种结合是浓度依赖并能为游离的TMTP1所拮抗;荧光显微镜检测小鼠肿瘤及正常组织器官冰冻切片显示FITC-TMTP1在肿瘤原发灶及转移灶的荧光信号强度也要显著强于正常组织器官。结论筛选获得的短肽TMTP1可以特异地与高转移潜能的前列腺癌细胞结合,为前列腺癌的靶向诊疗提供一种可能的标志物及靶向载体。

英文摘要：

Objective To select polypeptide fragment which binds to the highly metastatic prostate cancer PC-3M-1E8 cell line in vitro screened by Fli Trx bacterial peptide display system.Methods Targeting peptides were selected in vitro by screening of the Fli Trx library with the paired highly metastatic and nonmetastatic human prostate cancer cell lines PC-3M-1E8 and PC-3M-2B4.After bio-selection,the clones with the strongest binding capability were identified,the inserted and repeated motifs were selected and synthesized for further identification.The specific binding capacity of peptides was confirmed by binding assay,competitive inhibition assays and in vivo targeting studies.Results The target peptide sequences enriched in the selected clone pool was NVVRQ,which we named TMTP1.Binding assay revealed that FITC-TMTP1 specially bounds to highly metastatic prostate cancer cell PC-3M-1E8,but did not bind to the non-metastatic tumor PC-3M-2B4;binding of FITC-TMTP1 and PC-3M-1E8 was concentration-dependent and could be competitively inhibited by free synthetic TMTP1.After i.v.injection,FITC-TMTP1 also specifically targeted primary and metastatic tumors induced by PC-3M-1E8.Conclusion TMTP1 targets highly metastatic prostate cancer cells in vitro and in vivo.It suggests that TMTP1 is a potential strategy for the development of new diagnostic tracers or alternative anticancer carrier for prostate cancer.