[Expression of extracellular matrix (tenascin) in the gastric cancer--an immunohistochemical study]

Expression and distribution of tenascin (TN) were immunohistochemically studied in the primary and metastatic sites of 90 cases of resected gastric cancer. TN was present in stromal cells surrounding cancer nests, but not in cancer cells. The overall incidence of TN-positive cases in the primary site was 70%, and the incidence in advanced cancer cases was significantly higher than that in early cancer cases. The incidence of TN-positive cases was significantly higher in the metastatic site than in the primary site. TN tended to be expressed intensively in the periphery of tumors. Coexpression of fibronectin (FN) and TN was observed in 50% of the TN-positive cases. However, the cases, in which TN was strongly positive in the periphery of tumors, were not reactive with anti-FN antibody. Ki-67 monoclonal antibody was also utilized to compare the number of proliferating cells in the TN-positive cases with that in the TN-negative cases. The number of Ki-67-positive cells was larger in the TN-positive cases than in the TN-negative cases. These results suggest that TN would be related to progression and metastasis of the gastric cancer, and that its biological function would be different from that of FN.