目的　探讨Stat3、CyclinD1和Bcl-2三种Stat3通路上的蛋白在食管鳞状细胞癌（esophageal squamous cell carcinoma, ESCC）发生中的作用及其在早期诊断中的意义。  方法　制作组织芯片，包含有860例ESCC组织、198例不典型增生组织、201例单纯增生组织及467例癌旁正常上皮组织，应用免疫组化方法检测三种蛋白的表达情况。  结果    （1）ESCC中三种蛋白的表达均显著高于癌旁单纯增生和正常上皮组织（P<0.05）。（2） 随着ESCC分化程度由高到低，Stat3和Bcl-2蛋白的表达逐渐增强，而CyclinD1的表达逐渐减弱。（3）三种蛋白在ESCC中的表达与患者的年龄、性别、发生部位、肿瘤大小及大体分型差异无统计学意义（P>0.05），与癌组织浸润深度及淋巴结转移有关（P <0.05）。（4）ESCC中Stat3与CyclinD1的表达呈负相关（r=-0.699，P=0.000）；与Bcl-2的表达呈正相关（r=0.660，P=0.000）；但是CyclinD1与Bcl-2的表达无相关性。  结论　Stat3、CyclinD1和Bcl-2可能在ESCC的发生发展和浸润转移中有重要的作用，CyclinD1和Bcl-2的表达检测有助于ESCC的早期诊断。

Objective　To investigate the roles of Stat3, CyclinD1 and Bcl-2 in the tumorigenesis and early diagnosis of esophageal squamous cell carcinoma (ESCC).　Methods　Using tissue microarray (TMA) technique and immunohistochemistry (IHC) method, Stat3, CyclinD1 and Bcl-2 protein expression were detected in tissue specimens of ESCC (860 cases), dysplasia (198 cases), basal cell hyperplasia (201 cases) and normal mucosa adjacent to cancer tissue (467 cases).　Results　(1) Stat3, CyclinD1 and Bcl-2 proteins were respectively detected in ESCC and dysplasia, which were significantly higher than that of other control group (P<0.05). (2) The expression of Stat3 and Bcl-2 protein were gradually increased, but CyclinD1 reduced, from the well to poorly differentiated ESCC. (3) The expression of Stat3, CyclinD1 and Bcl-2 significantly related to lymph node metastasis and infiltration depth (P<0.05), but not correlated with the age, gender, primary location, the size of tumor and gross appearance type (P>0.05). (4) There was significantly negative association between Stat3 and CyclinD1 (r=-0.699, P=0.000), however, the expression of Stat3 was positive related to the Bcl-2 expression(r=0.660, P=0.000).　Conclusions　Stat3, CyclinD1 and Bcl-2 may play important roles in tumorigenesis and progression of ESCC. Detection of CyclinD1 and Bcl-2 proteins may be helpful for the early diagnosis of ESCC.