Cellular retinol-binding proteins in head and neck tumors and their adjacent tissues

The levels of cellular retinol-binding protein (CRBP) were examined by Scatchard analysis in 17 surgically resected human head and neck tumors and their adjacent normal tissues (normal tissues corresponded to muscle tissue). The center area and the marginal area of tumors were tested for their levels of CRBP in 17 cases, and the adjacent tissue was tested in 13 of the 17 cases. Only a small difference (if any) in the dissociation constant (Kd values) was seen in some cases between tumor and adjacent tissue; in most cases the Kd values in both areas were similar, and these values were also similar between the central and marginal areas of tumors. The average level of CRBP in the marginal area of the tumors was higher than that in the center area of the tumors in all the 17 cases. Among the 13 tumor cases whose adjacent tissues were tested, 12 showed CRBP levels more than two times higher in the marginal area of tumors; whereas in only one case was the level in the marginal or the center area of tumor similar to that in the adjacent tissues.