Qiu Cheng-Zhi, Wang Chuan, Huang Zhong-Xin, Zhu Shi-Ze, Wu You-Yi, Qiu Jian-Long
Department of General Surgery, Second Affiliated Hospital of Fujian Medical University, Quanzhou 362000, Fujian Province, China.
World J Gastroenterol. 2006 Apr 7;12(13):2011-5. doi: 10.3748/wjg.v12.i13.2011.
To study the SSTR1, 2, 3, 4, 5 expression and their relationships with clinico-pathological factors, cell proliferation, Bcl-2 and p53 expression in colorectal cancer cells.
Immunohistochemical staining of five SSTR subtypes, Ki-67, Bcl-2 and p53 was performed by the standard streptavidin-peroxidase (SP) technique for the paraffin sections of 127 colorectal cancers. and expression of five SSTR subtypes in 40 specimens of normal colorectal mucosae was detected with the same method.
Positive staining for five SSTR subtypes was observed in colorectal cancer cells and normal colorectal mucosae. SSTR1 was the most predominant subtype in both colorectal cancer and normal colorectal mucosa, and the second was SSTR5 or SSTR2. As compared with normal colorectal mucosa, SSTR4 was more frequently expressed in colorectal cancer cells (2.5% vs 18.9%, P<0.05); the expression of SSTR2, 4, 5 in moderately to well differentiated colorectal adenocarcinoma was significantly higher than that in poorly differentiated ones (P<0.05), the SSTR1 expression in colorectal cancer with positive lymph node metastasis was significantly higher than that with negative lymph node metastasis (72.2% and 54.5%,P<0.05). In addition, in the ulcerative type of colorectal cancer, SSTR2 expression was obviously decreased (P<0.05); the correlation did not reach a statistical significance between the five SSTR subtypes expression and Dukes'stages (P>0.05), but the frequency of SSTR1 expression increased with Dukes'stage, while SSTR3 and SSTR5 expression decreased with Dukes' stage. Moreover, there was no correlation between expression of the five SSTR subtypes and other clinicopathological factors such as age, sex, tumor site, tumor depth, distant metastasis. The proliferative indexes in colorectal cancer cells with negative expression of SSTR2 and SSTR3 were significantly higher than that with positive expression (P<0.05). The Bcl-2 expression in colorectal cancer cells with positive expression of SSTR1, 2, 3, 5 was significantly lower than that with negative expression (P<0.05). There was no correlation between five SSTR subtypes and p53 expression.
The most predominant SSTR subtype is SSTR1, and the second is SSTR2 or SSTR5. Five SSTR subtypes play different roles in the development of colorectal cancer. SSTR2 and SSTR3 can inhibit the proliferation and promote apoptosis of tumor cells.
研究SSTR1、2、3、4、5在大肠癌细胞中的表达及其与临床病理因素、细胞增殖、Bcl-2和p53表达的关系。
采用标准链霉亲和素-过氧化物酶（SP）技术对127例大肠癌石蜡切片进行5种SSTR亚型、Ki-67、Bcl-2和p53的免疫组化染色。用同样方法检测40例正常大肠黏膜中5种SSTR亚型的表达。
在大肠癌细胞和正常大肠黏膜中均观察到5种SSTR亚型的阳性染色。SSTR1是大肠癌和正常大肠黏膜中最主要的亚型，其次是SSTR5或SSTR2。与正常大肠黏膜相比，SSTR4在大肠癌细胞中的表达更频繁（2.5%对18.9%，P<0.05）；SSTR2、4、5在中高分化大肠腺癌中的表达明显高于低分化腺癌（P<0.05），有阳性淋巴结转移的大肠癌中SSTR1的表达明显高于无淋巴结转移者（72.2%和54.5%，P<0.05）。此外，在溃疡性大肠癌中，SSTR2的表达明显降低（P<0.05）；5种SSTR亚型表达与Dukes分期之间的相关性未达到统计学意义（P>0.05），但SSTR1的表达频率随Dukes分期增加，而SSTR3和SSTR5的表达随Dukes分期降低。而且，5种SSTR亚型的表达与年龄、性别、肿瘤部位、肿瘤深度、远处转移等其他临床病理因素之间无相关性。SSTR2和SSTR3阴性表达的大肠癌细胞增殖指数明显高于阳性表达者（P<0.05）。SSTR1、2、3、5阳性表达的大肠癌细胞中Bcl-2的表达明显低于阴性表达者（P<0.05）。5种SSTR亚型与p53表达之间无相关性。
最主要的SSTR亚型是SSTR1，其次是SSTR2或SSTR5。5种SSTR亚型在大肠癌的发生发展中发挥不同作用。SSTR2和SSTR3可抑制肿瘤细胞增殖并促进其凋亡。
