Detection of metastasis-associated differences for receptors of glycoconjugates (lectins) in histomorphologically unchanged xenotransplants from primary and metastatic lesions of human colon adenocarcinomas.

Clinically applicable markers for tumor progression may be uncovered by selective analysis of biochemical parameters, supposedly participating in this complex process. Owing to the importance of specific protein-carbohydrate interactions in diverse biological processes, the pattern of the receptor part in this glycobiochemical recognition system, the sugar receptors (lectins), conceivably reflects biological properties of tumor cells in glycobiochemical terms. Therefore, we established and characterized xenografts from surgically removed specimens of a human primary colon adenocarcinoma and its metastatic lesions to liver of the same patient and of a histomorphologically similar primary colon adenocarcinoma of another patient in nude mice. Xenotransplantation and subsequent glycobiochemical analysis of material from early passages with a standardized procedure had been preferred to cell culture in monolayer on account of maintenance of a higher degree of organized histotypic assembly. Despite histomorphological similarities, the sugar receptor profile revealed significant differences in tumor-tumor and tumor-metastasis comparison, especially for alpha- and beta-galactoside-binding proteins. Tumor-metastasis differences were substantiated by a second successfully xenotransplanted pair of specimens. Comprehensive expansion of these initial data may eventually lead to desirable functional correlations with the different biological properties of histomorphologically similar primary colon adenocarcinomas and of the metastatic phenotype and to a rational development of therapeutic modalities to restrict tumor growth and spread.