Interrelation between expression of matrix metalloproteinase 7 and β-catenin in esophageal cancer

Matrix metalloproteinase 7 (MMP-7) may play a key role in the progression of various human malignant tumors. Nuclear β-catenin enhances the activating expression of MMP-7 genes by binding with the T-cell factor/lymphoid enhancer factor family of transcription factors. We immunohistochemically examined the expression of MMP-7 and β-catenin to better understand the significance of these factors in the progression of esophageal squamous cell carcinoma. The entire coding region of β-catenin exon 3 was also analyzed by direct sequencing in all cases. We found that MMP-7 was expressed in 7 (20.6%) of 34 esophageal squamous cell carcinomas. There was a significant relationship between MMP-7 expression and tumor invasion into adjacent structures (P < 0.05). Aberrant nuclear expression of β-catenin was found in 12 of 34 (35.3%) esophageal cancers and correlated with MMP-7 expression, the statistical difference being (P < 0.05). None of the 34 esophageal cancers examined carried mutations in β-catenin exon 3. MMP-7 expression correlates with penetrating tumor progression in esophageal cancer. Nuclear translocation of β-catenin, without mutations in β-catenin exon 3, is associated with MMP-7 expression.