生长抑素受体亚型在结直肠癌组织中的表达

Expression of 5 somastatin receptor subtypes in colorectal cancer tissues

目的 探讨结直肠癌组织中生长抑素受体亚型(SSTR1 SSTR5 )的表达和临床病理学意义。方法 免疫组织化学染色方法(SP法)检测12 7例结直肠癌组织和40例正常结直肠黏膜中SSTR 5种亚型的表达。结果 SSTR 5种亚型在结直肠癌组织和正常结直肠黏膜均有表达,两组SSTR表达的优势亚型都是SSTR1,结直肠癌组织中SSTR4表达明显高于正常结直肠黏膜(18.9%比2 .5 % ,P <0 .0 5 )。SSTR2、SSTR4、SSTR5在中高分化结直肠癌表达明显高于低分化结直肠癌表达(P <0 .0 5 ) ;淋巴结转移的结直肠癌SSTR1表达明显高于无淋巴结转移者(72 .2 %比5 4.5 % ,P <0 .0 5 ) ;溃疡型结直肠癌SSTR2表达明显降低(P <0 .0 5 ) ;此外,SSTR1表达率随Dukes分期呈升高趋势,而SSTR3 ,SSTR5则呈下降趋势,但没达到统计学水平。SSTR5种亚型表达均与患者年龄、性别、肿瘤位置、浸润深度、远处转移无明显相关。结论 结直肠癌组织中SSTR1是优势表达亚型,SSTR2、SSTR4、SSTR5亚型表达与癌恶性程度有关,可能在结直肠癌发展过程中发挥重要作用。

Objective To study the expression of SSTR1,SSTR2,SSTR3,SSTR4 and SSTR5 in colorectal cancer tissues and their relationships with cliniopathological features.Methods Immunohistochemical staining of 5 SSTR subtypes was performed by the standard streptavidin-peroxidase (SP) technique for the paraffin sections of 127 cases of colorectal cancer and 40 cases of normal colorectal mucosae.The relationship between the 5 SSTR subtypes expression in colorectal cancers and the clinicopathological parameters was analyzed.Results Positive staining for all 5 SSTR subtypes was observed in colorectal cancer tissues and normal colorectal mucosae.The clear predominance of SSTR subtypes expression in colorectal cancer and normal tissue was SSTR1.As compared with normal colorectal mucosae,SSTR4 was more frequently expressed in colorectal cancer ( P < 0.05). The expression of SSTR2,SSTR4 and SSTR5 in middle to well differentiated colorectal adenocarcinoma was significantly higher than that in poorly differentiated colorectal adenocarcinoma ( P < 0.05).The expression of SSTR1 in colorectal cancer with positive lymph node metastasis was significantly higher than negative lymph node metastasis (72.2% vs 54.5%, P < 0.05). Although this difference had no statistical significance between SSTR1,SSTR3,SSTR5 and Dukes'stage,the expression of SSTR1 was increased with Dukes' stage,while SSTR3 and SSTR5 decreased with Dukes' stage.The SSTR2 expression was obviously decreased in the ulcerative type of colorectal cancer ( P < 0.05). However,there was no correlation between the expression of the 5 SSTR subtypes and other clinicopathological parameters such as age,sex,tumor site,invasive depth and distant metastasis.Conclusion SSTR1 was the predominant SSTR subtype in colorectal cancer.The expression of SSTR2,SSTR4,SSTR5 was correlated with malignant degree of colorectal cancer and may play an important role in the progression of colorectal cancer.SSTA that has a high affinity for SSTR5 should be chosen to treat colorectal cancer.