Abstract: Objective: To investigate the expression of matrix metalloproteinase-1 (MMP-1) and vascular endothelial growth factor-C (VEGF-C) in human esophageal squamous cell carcinoma (ESCC),and their relationship with the clinicopathological parameters.Methods: The expressions of MMP-1 and VEGF-C were determined immunohistochemically in 90 cases of human esophageal squamous cell carcinoma,16 cases of severe dysplasia/carcinoma in situ and 28 cases of adjacent normal tissues.Results: The positive expression rates of MMP-1 in ESCC,severe dysplasia/carcinoma in situ and adjacent normal tissues were 81.11%,81.25% and 17.86%,respectively.The expression of MMP-1 was associated with the depth of invasion,lymph node metastasis and clinical staging in ESCC,but not with differentiation (P>0.05).The positive expression rates of VEGF-C in ESCC,severe dysplasia/carcinoma in situ and adjacent normal tissues were 83.33%,75.00% and 25.00%,respectively (P<0.01);the expression of VEGF-C was associated with the lymph node metastasis and clinical staging in ESCC (P<0.01 and P<0.05),but not with the differentiation or depth of invasion (P>0.05).And there was a positive correlation between MMP-1 and VEGF-C (P<0.01).Conclusions: MMP-1 and VEGF-C play a crucial role in invasion and lymphatic metastasis.They are important predictors of biological behavior in ESCC.