环行七肽CGNSNPKSC的受体鉴定及其在胃癌中的表达

目的：探讨血管特异结合短肽CGNSNPKSC在胃癌中的表达及与肿瘤分化程度的关系;初步筛选短肽CGNSNPKSC的受体.方法：采用免疫组化SP法检测CGNSNPKSC在胃癌中的表达及与分化程度的关系;以CGNSNPKSC作为＂探针＂免疫筛选表达型λZAP噬菌体cDNA文库,筛选CGNSNPKSC可能的受体,并利用生物信息学对阳性克隆进行初步分析.结果：CGNSNPKSC受体在高,中,低度分化胃癌的血管中表达率依次为12/18（67%）,17/23（74%）,22/24（92%）;在低分化胃癌组织中的表达明显高于高分化和中分化胃癌组织（P＜0.05）.cDNA文库筛选获得43个独立候选克隆,生物信息学显示分属于13种不同的基因.结论：CGNSNPKSC与胃癌的血管特异结合,可作为肿瘤血管抑制治疗的靶向载体.

Identification of the receptor of CGNSNPKSC and its expression in gastric cancer

Objective: To detect the expression of vascular-binding peptide CGNSNPKSC in gastric cancer and to identify its possible receptor. Methods: Immunohistochemical analysis was used to detect the expression of CGNSNPKSC in gastric cancer and its relation with tumor type. A micro-vascular cDNA library was screened to detect the receptor of CGNSNPKSC, and the possible inserts were further identified by bioinformative assay. Results: CGNSNPKSC was found in 51/65 (78%) cases of gastric cancer tissues, including 12/18 (67%) cases of well-differentiated tissues, 17/23 (74%) cases of moderate-differentiated tissues and 22/24 (92%) cases of poor-differentiated tissues. Statistical analysis showed that there was significant correlation between the expression of CGNSNPKSC and the differentiation of gastric cancer. After four rounds of selection, 43 clones (designated C1-C43) were found showed reactivity to CGNSNPKSC. Sequence analysis and on-line homology analysis revealed that these inserts belonged to 13 genes. Conclusion: These results took further insight into the characteristic of CGNSNPKSC, and strongly suggested that CGNSNPKSC might be used as vehicle delivering cytokine or chemotherapy in targeting gastric cancer therapy.