Abstract: OBJECTIVE: To detect WW domain containing oxidoreductase gene(WWOX)expression and test abnormal promoter methylation of WWOX gene in esophageal squamous cell carcinoma(ESCC). METHODS: RT_PCR and methylation_ specific PCR (MSP) methods were used to detect WWOX gene expression and WWOX promoter methylation in 69 ESCC tissues and 48 corresponding normal tissues. RESULTS: WWOX gene was methylated in 18 of 69 (26.1％) tumor specimens, which was significantly higher than that in corresponding normal tissues (4.2％,2/48,P=0.002). Methylation frequencies of stagesⅢandⅣtumor tissues (43.3％) were higher than those of stagesⅠandⅡtumor tissues (12.8％)(P=0.004). Methylation frequencies of poorly differentiated group (33.3％) were higher than those in moderate_(20％)and poor_moderate differentiated groups (26.2％), but it did not show significant difference (P>0.05). Expression level of WWOX gene mRNA in esophageal cancer tissues was significantly lower when compared with the corresponding normal tissues. No significant correlation was found between the expression level of WWOX gene mRNA and clinical data (P>0.05) in ESCC tissues. CONCLUSION: The aberrant promoter methylation of WWOX gene was related to tumorigenesis and progression of esophageal squamous cell carcinoma.

Key words: esophageal squamous cell carcinoma, WW domain containing oxidoreductase gene(WWOX);methylation