SIGNIFICANCE OF ALPHA-1-ANTITRYPSIN MESSENGER-RNA EXPRESSION IN ESOPHAGEAL-CARCINOMA

Alpha-1-antitrypsin (alpha 1AT) is present not only in the normal gast rointestine, but in malignant gastrointestinal tissue as well. We stud ied the expression of alpha 1AT mRNA in 30 cases of esophageal carcino ma using a Northern blot analysis. In addition, we also examined the e xpression of matrix metalloproteinase 7 (MMP7) mRNA in the latest 15 c ases by reverse transcriptase-polymerase chain reaction (RT-PCR) metho d to clarify the relationship between the alpha 1AT and MMP7. In 25 of the 30, the expression of alpha 1AT mRNA in esophageal carcinomatous tissue (T) was lower than that in the corresponding normal tissue (N) of the esophagus. The T/N ratio of alpha 1AT mRNA expression showed a significant inverse correlation with the depth of tumor invasion, lymp h node metastasis and stage of disease (p=0.042, p=0.0001 and p=0.002, respectively). The T/N ratio of alpha 1AT bad a converse correlation with that of MMP7 (p=0.034). The current study thus suggested that i) the lower expression of T/N expression may be a marker for the biologi cal aggressiveness of esophageal carcinoma, and ii) the reduction of a lpha 1AT may be partially correlated with the overexpression of MMP7 i n tumor tissue.