中文摘要：

目的：获得与胃癌耐药细胞株SGC7901／VCR特异结合的抑制耐药短肽，作为提高胃癌化疗效果的先导化合物。方法：以SGC7901／VCR细胞为靶细胞，胃粘膜永生化上皮细胞GES，胃癌药敏细胞SGC7901为吸附细胞对噬菌体7肽库进行消减筛选，用细胞ELISA鉴定阳性噬菌体克隆并测序，利用竞争抑制试验确定阳性克隆的结合部位是否为外源性肽段。结果：经4轮筛选，从随机挑选的30个噬菌体克隆中得到14个能特异性与SGC7901／VCR结合而不与胃癌药敏细胞结合的阳性克隆，确定其氨基酸序列分别为SYl和SY2（筛选所得安基酸序列正在专利申请中），含SY1为阳性克隆。结论：用噬菌体环7肽库成功筛选到能特异性结合胃癌耐药细胞株的短肽，为肿瘤治疗或药物靶向治疗奠定基础。

英文摘要：

Objective：To obtain short peptides which specifically bind to drug resistant cells by means from 7 peptide libraries. Methods： Multidrug- resistant gastric cancer cells SGC7901/VCR were used as the target cells and GES as the absorber cells as well drug - sensitive gastric cancer cells SGC7901 for subtraction biopanning from a Ph. D. -C7C library. The positive phage clones were identified by cell enzyme -linked immunosorbent assay （ELISA）, and the amino acid sequences were deduced by DNA sequencing. Results. After 4 rounds of screening, the 14 positive phage clones were identified only specific bind to the SGC -7901/VCR of human gastric cancer not to SGC - 7901, DNA sequence was CTLQNRTLC and CGASNLKSC, the phages containing CTLQNRTLC were positive. Conclusion： A candidate peptide special binding to gastric resistant cancer can be selected, thus providing the potential for improving gastric tumor chemotherapy or targeted drug delivery in chemotherapy.