Association between tumor DNA aneuploidy and in vitro tetraploidy of skin fibroblasts in patients with colorectal neoplasms.

Abstract

In vitro tetraploidy (IVT) in cultures of skin fibroblasts was compared with tumor DNA ploidy, as determined by flow cytometry on paraffin-embedded material, in 99 patients with colorectal neoplasm. In 63 patients with non-heritable carcinoma we found a significant correlation between the number of aneuploid stemlines in the tumor and IVT in the fibroblast culture. Furthermore, tumor aneuploidy was significantly correlated to the size of the tetraploid subpopulation in the fibroblasts. There was no correlation between aneuploidy and Dukes's stage or the degree of differentiation. In 36 patients with adenoma no correlation between tumor aneuploidy and fibroblast IVT was demonstrated, whereas the number of tumor stemlines was significantly correlated to histopathologic stage and grade of dysplasia. IVT in cultured skin fibroblasts, which has been reported to reflect a genetic predisposition to colorectal cancer in heritable colon cancer syndromes, thus seems to be relevant also for the understanding of tumor formation and progression in the 'non-heritable' type of colorectal cancer.