Relationship between endostatin expression and the invasion of rectal cancer
ABSTRACT: Objective To investigate the relation of endostatin (ES) and the vascular formation in rectal cancer, and the effect of ES on the invasion of rectal cancer. Methods The expression level of ES and microvessel density (MVD) in 10 cases of normal rectal tissues and 40 cases of rectal cancer were detected by immunohistochemistry staining. Results The expression level of ES in normal rectal tissues was obviously stronger than that in rectal cancer (P<0.0
5). There was a negative relation between the expression level of ES and MVD in rectal cancer with the changes of the depth of infiltration and lymph node metastasis (P<0.0
5). Conclusion With the decrease of ES, the number of knubbly vessels increases. The decrease of ES can promote infiltration of rectal cancer and metastasis of lymph node.
KEY WORDS: endostatin; microvessel density; rectal cancer
1 材料与方法
1.4 统计学方法 采用SPSS10.0统计软件进行统计学处理，实验数据用均数±标准差(±s)表示，组间比较采用单因素方差 分析 ，相关分析采用秩和检验。P<0.05为差异具有统计学意义。
2 结果
2.1 正常直肠组织与直肠癌组织中ES的表达及MVD ES阳性表达主要在正常直肠黏膜组织。直肠癌组织中边缘区细胞ES染色要强于中心区，一些坏死组织周边区也可见到强阳性染色出现。直肠癌组织的MVD明显高于正常黏膜组织(P<0.05，表
1)。
表1 正常直肠组织与直肠癌组织中ES 的表达及MVD（略）
Table 1 The expression level of ES and MVD in normal rectal tissues and rectal cancer
*P<0.05 vs. normal rectal tissue
2.2 直肠癌组织中ES的表达、MVD与临床病理特征的关系 依癌组织浸润深度分为黏膜层、肌层、全层三组，随浸润深度的增加，直肠癌组织中ES表达与MVD呈负相关关系(rs=-0.786, P<0.0
5)。直肠癌浸润越深，ES蛋白的表达越低，而MVD增加(表
2)。
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表2 直肠癌的浸润深度与ES表达及MVD的关系（略）
Table 2 The effect of the expression level of ES and MVD on the depth of infiltration in rectal cancer
△P<0.05 vs. mucous membrane; *P<0.05 vs. mucous membrane and muscular layer
2.3 直肠癌组织中ES的表达、MVD与淋巴结转移的关系 按淋巴结转移情况分为有淋巴结转移与无淋巴结转移两组，两组间直肠癌组织中ES表达及MVD有显著性差异(P<0.05，表
3)。
表3 淋巴结转移与ES表达及MVD的关系（略）
Table 3 The effect of the expression level of ES and MVD on the lymph node metastasis in rectal cancer
*P<0.05 vs. no lymph node metastasis
3 讨论
