结直肠癌组织中Ang-2、Tie-2 mRNA的表达及K-ras基因突变的检测

Expression of Ang-2,Tie-2 mRNA and K-ras gene mutation in human colorectal cancer tissue

目的:探讨结直肠癌组织中促血管生成素-2(Ang-2)及酪氨酸激酶受体-2(Tie-2)mRNA的表达及K-ras基因突变的意义。方法:采用实时荧光定量PCR法分析40例结直肠癌组织和10例正常结肠黏膜组织中Ang-2及Tie-2的表达,应用PCR-SSCP方法检测40例结直肠癌组织中K-ras基因突变情况。结果:结直肠癌组织中Ang-2和Tie-2 mRNA的表达量高于正常组织(t=39.960、9.490,P<0.05)。K-ras基因突变率达42.5%(17/40),其中12密码子突变11例(64.7%),13密码子突变6例(35.3%)。浸润达肌层、有淋巴结转移和低未分化癌组织Ang-2mRNA高表达率较高(χ2=6.593、10.165、5.974,P均<0.05),Dukes分期C和D期、浸润达肌层、有淋巴结转移和低未分化癌组织Tie-2 mRNA高表达率也较高(χ2=4.365、8.864、8.087和9.086,P<0.05)。K-ras基因突变率在淋巴结转移的结直肠癌组织中高于无转移者(χ2=6.320,P<0.05),Dukes分期C、D期癌组织高于A、B期(χ2=13.961,P<0.05)。存在K-ras基因突变的癌组织中Ang-2和Tie-2 mRNA表达水平高于无突变者(t=4.056,7.518,P<0.05)。结论:Ang-2、Tie-2的表达与结直肠癌的血管生成以及早期转移有关。K-ras基因突变可作为评估结直肠癌转移和预后的分子生物学指标之一。

Aim：To investigate the expressions of angiopoietin-2 （Ang-2）, tyrosine kinase receptor-2 （Tie-2） mRNA and K-ras gene mutation in colorectal cancer tissues and explore the significance .Methods：Ang-2 and Tie-2 mRNA ex-pressions in 40 cases of colorectal cancer tissue and 10 cases of normal tissue were detected by Real-time PCR, and PCR-SSCP was used to detect K-ras gene mutation .Results：The expressions of Ang-2 and Tie-2 mRNA in colorectal cancer tis-sue were significantly higher than those in normal tissue （t=39.960,9.490,P〈0.05）.K-ras gene mutation was found in 17 cases（42.5%）, among which 11 cases（64.7%） were detected mutation in codon 12,and 6 cases （35.3%） in codon 13.Ang-2 mRNA expression was related to invasion depth , lymph node metastasis and tumor cell differentiation （χ2 =6.593,10.165,5.974, P〈0.05）.Tie-2 mRNA expression was related to Dukes stage ,invasion depth, lymph node metas-tasis and tumor cell differentiation （χ2 =4.365,8.864,8.087,9.086, P〈0.05）.K-ras gene mutation was related to Dukes stage and lymph node metastasis （χ2 =13.961,6.320, P〈0.05）.The expressions of Ang-2 and Tie-2 mRNA in the colo-rectal cancer tissue with K-ras gene mutation were higher than those without K-ras gene mutation （ t=4.056,7.518,P〈0.05）.Conclusion：Ang-2 and Tie-2 may play important roles in angiogenesis and metastasis , and K-ras gene can be used to evaluate the prognosis and metastasis of colorectal cancer .