Correlation of malignancy and expression of cytokeratin in human gingival and rhinopharyngeal cancers xenografted into nude mice

Abstract

We investigated cytokeratin (K) expression in well-differentiated human gingival (GK-1) and poorly-differentiated rhinopharyngeal (KB-N) cancer xenograft lines in nude mice. GK-1 expressed Ks 1, 5, 6, 8, 10, 11, 14, 18 and 19, and KB-N expressed Ks 5, 6, 7, 8, 10, 13, 14, 17, 18 and 19. Immunoblotting analysis produced expression of various molecular sizes of K 18 in both lines, and of K 19 in GK-1. Immunohistochemical studies indicated that, compared with GK-1, KB-N reacted strongly and widely with anti CK 8, 18 and 19 antibodies. K 8 of GK-1 showed a stronger reaction in the peripheral cells of the cancer nest, while K 19 expression was stronger in large cancer nests. These results suggest that expression of Ks 1, 8, 18 and 19, and chemical changes in K protein have a strong correlation with malignancy in head and neck cancer.