Published online Dec 15, 2002. doi: 10.3748/wjg.v8.i6.971
Revised: July 12, 2002
Accepted: July 26, 2002
Published online: December 15, 2002
AIM: To study the expression of early growth response gene-1 (Egr-1 gene) and Bcl-X/L protein and its relationship with the cell apoptosis in human esophageal carcinoma(EC) and precancerous lesions.
METHODS: In situ hybridization(ISH), immunohistochemistry (IHC) and TUNEL method were used respectively to detect Egr-1mRNA,Egr-1 protein, apoptosis related-protein Bcl-X/L and cell apoptosis in situ from 66 cases of esophageal squamous cell carcinoma and their upper cut edge and paracancerous mucosa.
RESULTS: Egr-1 gene in situ hybridization, Bcl-X/L immunohistochemistry positive products were located in the cytoplasm, while Egr-1 immunohistochemistry and TUNEL positive signal were located in the nuclei. The apoptosis index(AI) and the frequency of apoptosis occurrence were increased gradually from precancerous lesion to cancer (P < 0.01) and the expression of Egr-1mRNA and Egr-1 protein in dysplasia was the highest among all specimens (P < 0.01). The AI of Egr-1 positive cancer tissues was much higher than that of Egr-1 negative cancer tissues (P < 0.01), while the AI of Bcl-X/L positive cancer tissues was much lower than that of Bcl-X/L negative cancer tissues (P < 0.01). The AI and Egr-1 expression were not correlated with invasiveness and lymphatic metastasis in EC.
CONCLUSION: Cell apoptosis was present through esophageal carcinogenesis. The expression of Egr-1 mRNA and Egr-1 protein were high in precancerous lesion of esophagus. The AI was increased significantly in Egr-1 positive squamous cell carcinoma. Egr-1 might promote apoptotic effect. Egr-1 expression and cell apoptosis may have an important biological significance in esophageal carcinogenesis.