OBJECTIVE To investigate the expression of RECK mRNA and protein in esophageal squamous cell carcinoma （ESCC） and to examine its relationship with the clinicopathologic features. METHODS The expression of RECK mRNA and protein in 62 cases of ESCC, 31 of paraneoplastic atypical hyperplasia （PAH） and 62 normal esophageal mucous membrane specimens was examined, using RT-PCR and immunohistochemistry. RESULTS During canceration of the ESCC, the mRNA of RECK increased sequentially from ESCC tissue to PAH and normal mucous membranes. Values were 1.052±0.078, 1.274±0.235 and 1.306±0.121, respectively, with a significant difference among different groups （F=49.936, P〈0.05）. There was a statistically significant difference in the relative amount of the RECK mRNA among the ESCC tissues at various levels of differentiation, depth of infiltration, and different types of lymph node metastasis （F=5.081, F=26.084, U=24.011, P〈0.05）. In the ESCC tissue and PAH, the positive rates of RECK protein expressions were lower compared to the normal mucosa tissue, i.e. 59.7% （37/62）, 71.0% （22/31） and 85.5% （53/62）, respectively. There was a significant difference among the inter-group comparisons （Х^2=10.331, P〈0.01）. In ESCC, there was a close correlation between the RECK protein expression and the degree of cancer differentiation, and the depth of invasion and the types of ESCC lymph node metastasis （P〈 0.05）. CONCLUSION The decrease in expression of both RECK mRNA and protein in ESCC suggest that these low expressions may relate to ESCC development. Examination of RECK mRNA and protein expression may develop into one of the molecular indices for early ESCC diagnosis and prognosis.
