Expression Analysis Of Transcription Factors Elk-1 & C-Jun/AP-1 In Human Esophageal Squamous Cell Carcinoma

AIM: To study the expression pattern of Ets-like protein 1 (Elk-1) in human esophageal squamous cell carcinoma (ESCC) and to analyze its relationship with clinicopathologic parameters.METHODS: The expression of Elk-1 in fresh esophageal cancer tissues and their corresponding normal mucosae was detected immunohistochemically (IHC) by means of tissue microarray (TMA). Its correlation with clinical characteristics was evaluated and analyzed by univariate analysis. All statistical analyses were performed by SPSS version 13.0.RESULTS: Expression level of transcription factor Elk-1 increased in 78.5% (84/107) ESCC tissues compared with their matched normal esophageal epithelium. However, the expression of Elk-1 did not show any obvious correlation with degree of differentiation of esophageal carcinoma (in well-differentiated, moderately-differentiated and poorly-differentiated tumors, the increased expression was 7/8, 60/74, and 19/25, respectively, P > 0.05). Moreover, no obvious correlation was found with lymph node metastasis and depth of invasion.CONCLUSION: Increased expression of transcription factor Elk-1 may play an important role in esophageal carcinogenesis and further researches will be needed to clarify the possible mechanism and correlation to prognosis. Transcriptional activation of eukaryotic genes depends on the precise and ordered recruitment of activators, chromatin modifiers, and general transcription factors to the promoters of target genes. Previously, we identified differentiation-associated genes were coordinately down-regulated in human esophageal squamous cell carcinoma (ESCC) including SPRRs (small proline-rich proteins), keratins, cystatin A and involucrin, all of which contain AP-1 DNA binding sites in the promoter regions. However, the mechanisms of down-regulation of these genes were poorly understood.We investigated the endogenous expression pattern of AP-1 ( activator protein-1) in paired ESCC tissue specimens. Coincident with the down-regulation of these genes, c-Jun expression was obviously decreased in cancer tissues. It suggested that the downregulation of c-Jun may be associated with the underexpression of differentiation-associated genes in ESCC.AIM: To study the expression of c-Jun in human esophageal squamous cell carcinoma (ESCC) and to analyze its relationship with clinicopathologic parameters.METHODS: The expression of c-Jun in fresh esophageal cancer tissues and their corresponding normal mucosae was detected immunohistochemically (IHC) by means of tissue microarray (TMA). Its correlation with clinical characteristics was evaluated and analyzed by univariate analysis. All statistical analyses were performed by SPSS version 13.0.RESULTS: Expression level of transcription factor c-Jun decreased in ESCC tissues compared with their matched normal esophageal epithelium (P<0.05). However, the expression of c-Jun did not show any obvious correlation with degree of differentiation of esophageal carcinoma (P>0.05). Moreover, no obvious correlation was found with lymph node metastasis and depth of invasion.CONCLUSION: Decreased expression of transcription factor c-Jun may play an important role in esophageal carcinogenesis and further researches will be needed to clarify the possible mechanism and correlation to prognosis.