生长抑素及类似物对大肠癌组织血管生成的调控

Antiangiogenic effects of somatostatin and its analogues in rectal cancer

目的 :研究生长抑素 (somatostatin ,SS)与大肠癌组织微血管密度 (MVD)及相关因子血管内皮细胞生长因子 (VEGF)和基质金属蛋白酶抑制剂 2(TIMP 2 )表达的相关性。方法 :应用免疫组织化学S P法 ,分析 80例手术切除的新鲜大肠癌标本SS ,CD34,VEGF ,TIMP 2的变化。结果 :大肠癌组织中SS表达阳性率为 6 6 .2 5 % ,SS高表达组的大肠癌MVD的表达显著低于SS低表达组 (P <0 .0 1) ,SS表达与TIMP 2表达呈明显正相关 (P <0 .0 5 ) ,与VEGF呈显著负相关 (P <0 .0 5 )。结论 :SS及VEGF ,TIMP 2在人体大肠癌组织中的表达有一定拮抗性。SS的抑癌机制之一可能是干扰了血管生长因子的合成 ,影响了细胞内调节细胞生长信号的传递 ,从而抑制肿瘤血管的生长。

AIM: To investigate the correlation between the somatostatin analogues (SS) and angiogenesis in colorectal carcinoma. METHODS: 80 cases of colorectal carcinomas were examined by immunohistochemical staining (S P method) using anti SS, anti VEGF and anti CD34 (+) monoclonal antibodies. RESULTS: SS positive staining was obtained in 53 out of 80 cases ( 66.25 %), and mainly in the cytoplasm of tumor cells. Microvessel density (MVD) expression was more intense in the negative group in comparison with others (P< 0.01 ). A significant correlation was found between the SS, VEGF and TIMP 2. The expression of VEGF in the SS positive group was lower than that in the negative group (P< 0.05 ), while that of TIMP 2 reversed (P< 0.05 ). CONCLUSION: There is certain antagonism between the expression of SS, VEGF and TIMP 2 in human colon cancer. One of the mechanisms of tumor inhibition by SS may be the interference with the synthesis of growth factors by tumor cells and with transmission of intracellular signals that regulates cell growth.