关键词: 癌基因C-myc, 抑癌基因PTEN, 免疫组织化学

Abstract: Abstract:Objective To investigate the correlation between the expressions of tumour suppressor gene PTEN and oncogene C-myc in colorectal carcinoma. Methods The expressions of PTEN and C-myc protein in normal colorectal mucosa(n＝8), adjacent non-cancerous tissues(n＝10) and primary colorectal carcinoma tissues(n＝60) were observed by S-P immunohistochemical assay. Results Of 60 colorectal carcinoma tissues, C-myc protein was detected in 46 cases. The expression rate of C-myc in the primary colorectal carcinoma tissues(76.70%) was significantly higher than that in the normal(0) and adjacent non-cancerous tissues(10%) (P<0.01). Overexpression of C-myc was significantly correlated with hepatic metastasis(r＝5.540, P<0.05) and was not related with TNM staging(r＝0.013, P>0.05). The positive expression rate of PTEN protein in the primary colorectal carcinoma tissues (25.00%,15/60) was significantly lower than that in the normal(100%) and adjacent non-cancerous tissues(90%) (P<0.01). PTEN protein expression was positively correlated with pathological differentiational degree(r＝0.869, P<0.05), negatively with TNM staging, lymph nodes metastasis and hepatic metastasis(r＝－0.791,r＝－0.741, r＝－0.634, P<0.05). The level of C-myc protein expression was negatively correlated with PTEN expression (r＝－0.322, P<0.001). Conclusion C-myc protein overexpression can not be used as a clinicopathological parameter to dignose colorectal cancer. The expression of PTEN is closely related to clinicopathological features in colorectal carcinoma, and could be used as a marker of tumour burden of colorectal carcinoma.

Key words: oncogene C-myc, anti-oncogene PTEN, immunohistochemistry