血管生成素2在口腔颌面部鳞癌中的表达及意义

Clinical significanee of angiopoietin-2 expression in oral squamous cell carcinoma

目的检测血管生成素2（Ang-2）在口腔颌面部鳞癌中的表达，分析其表达强度与淋巴结转移和临床分期等临床生物学行为的关系，并探讨Ang-2在口腔颌面部恶性肿瘤生长中的作用。方法采用实时荧光定量聚合酶链反应（PCR）法检测23例口腔颌面部鳞癌组织中Ang-2 mRNA的表达；采用免疫组化半定量法检测28例口腔颌面部鳞癌组织中Ang-2蛋白的表达。结果Ang-2 mRNA在口腔颁面部鳞癌组织中表达的dCt值为6．86±1．37，在癌旁无瘤组织中表达的dCt值为7．95±2．08，差异有统计学意义（P〈0．05）。Ang-2蛋白阳性染色定位于肿瘤细胞和血管内皮细胞的胞浆和胞膜中，在肿瘤组织及癌旁无瘤组织中的阳性表达率分别为53．6％和24．0％，差异有统计学意义（P〈0．05）。Ang-2 mRNA在淋巴结转移阴性和阳性组中表达的dCt值分别为7．16±1．49和6．48±1．16；在不同临床分期组（Ⅰ、Ⅱ期与Ⅲ、Ⅳ期）中表达的dCt值分别为7．11±1．63和6．49±1．10，差异均无统计学意义（均P〉0．05）。结论Ang-2参与了口腔颌面部肿瘤血管的形成。Ang-2 mRNA的表达强度与淋巴结转移及临床分期无明显的相关性，有待更大样本量的研究来进一步论证。

Objective To investigate the expression of angiopoietin-2 （Ang-2） and its clinical significance in oral squamous cell carcinoma. Methods The expression of Ang-2 mRNA was measured by real-time RT-PCR, and the expression of Ang-2 protein in tissue samples was detected by immunohistocbemical staining. Results The mean dCt value of Ang-2 mRNA expression in the cancer tissue was 6.86 ＋ 1.37, significantly lower than that in the paired adjacent non-cancerous tissue （7.95 ± 2.08,P 〈 0.05）, indicating a significantly higher expression of Ang-2 mRNA in the cancerous tissue than that in the adjacent non-cancerous tissue. The distribution of Ang-2 protein was found not only in the vascular endothelial cells but also in tumor cells. Semi-quantitative analysis revealed that the expression of Ang-2 protein in tumor specimens （ 53.6% ） was significantly higher than that （ 24. 0% ） in the paired adjacent non-cancerous tissue （P 〈 0.05 ）, the result was well consistent with that measured by RT-PCR. The dCt value of Ang-2 mRNA expression was 6.48 ± 1.16 in the patients with metastasis in lymph nodes versus 7.16 ± 1.49 in those without, with a non-significant difference between the two groups （ P 〉 0.05 ）. As regards the clinical stages, no significant difference was found between the expressions of Ang-2 mRNA in stage Ⅰ＋ Ⅱ（7.11±1.63 ） and stage Ⅲ ＋ Ⅳ cases （6.49±1.10,P〉0.05）.Condusion Angiopoietin-2 protein is expressed not only in vascular endothelial cells, but also in tumor cells, suggesting that angiopoietin-2 may take part in angiogenesis in oral squamous cell carcinoma. However, our results that high expression of angiopoietin-2 mRNA is not correlated with lymph node metastasis and clinical stages, needs to be further verified in a large scale study.