多肽pd20分子胃癌肝转移导向性的体内特异性鉴定

Specific Identification of Polypeptide Pd20 Target to Gastric Cancer with Liver Metastasis

目的鉴定胃癌肝高转移潜能细胞特异性结合肽pd20胃癌肝转移的导向性。方法构建胃癌肝转移的模型,通过归巢实验鉴定pd20噬菌体在胃癌肝转移裸鼠体内不同部位的归巢情况。竞争抑制实验来检测多肽pd20是否能抑制pd20噬菌体的归巢作用。免疫荧光实验检测多肽pd20在胃癌肝转移裸鼠体内的荧光分布情况。结果归巢实验显示:pd20噬菌体在胃癌和胃癌肝转移组织中回收滴度明显高于心、脾、肾等正常组织和对照噬菌体M13(P<0.05),而对照噬菌体M13在各组织中回收滴度之间的差异无统计学意义(P>0.05)。竞争抑制试验表明:随着多肽pd20的浓度增加,对pd20噬菌体归巢至胃癌肝转移组织的抑制作用越强(P<0.05)。免疫荧光实验结果显示:将多肽pd20携带绿色荧光,注入胃癌肝转移裸鼠体内,发现绿色荧光主要分布于胃癌和胃癌肝转移组织,而其他正常组织中荧光分布很少,或几乎没有荧光分布。结论裸鼠体内实验证实多肽pd20可能具有胃癌肝转移的导向性。

Objective To identify polypeptide pd20 whether has the ability home to gastric cancer with liver metastasis. Methods Gastric cancer with liver metastasis animal models were established. Homing trace of pd20 phage were explored in different organs of constructive animal models though homing test. Immunofluorescent technique was used to test the fluorescence distribution of pd20 phage in gastric cancer with liver metastasis nude mice. Results The recycling drop degrees of pd20 phage in both gastric cancer and gastric cancer with liver metastatic tissues were significantly higher than those in control phage and normal tissue such as heart,spleen,kidney and so on,while control phage had little difference among different tissues. The competitive inhibition tests showed that with the concentration of polypeptide pd20 increased,the pd20 phage home to gastric cancer with liver metastatic tissue were decreased. Polypeptide pd20 carrying green fluorescence were injected into gastric cancer with liver metastasis nude mice and found that green fluorescence mainly distributed in both gastric cancer and gastric cancer with liver metastatic tissues,while there were a little or even little distribution in other normal tissues. Conclusion The vivo tests confirmed that polypeptide pd20 possibly possess orientation for gastric cancer with liver metastasis.