Expression of c-ras oncogene and DNA ploidy in urinary bladder tumors

Oh, Bong Ryoul; Park, Yang Il; Min, Byung Kap

Abstract

Biological behavior of transitional cell tumors of the urinary bladder is related to many parameters, such as clinical staging, vascular invasion, expression of blood group antigens or oncogenes and DNA ploidy as well as histopathological grading. In most. however, the parameters have been evaluated separately in relation to histopathological grading or prognosis. although it is well known that biological behavior of a tumor can be predicted more reliable by analysis multiple parameters. In this study. the author tried to see the prognostic Relation ship between histopathological grading and expression of c-ras oncogene and DNA ploidy which have been defined recently. Immunohistochemical staining for c-ras oncogene products was performed in 40 cases of transitional cell tumors and positive tumor cells were estimated by light microscopy. DNA ploidy was determined by flow cytometry using the paraffin-embedded tissue. 1. By immunohistochemistry For c-ras oncogene products. the mean value of the positive cells was 35.1% in papillomas. 79.4% in grade I. 81.9% in grade X and 87.6% in grade III transitional cell carcinomas. 2. Analysis of DNA ploidy revealed diploidy in 8 and aneuploidy in 2 of 10 cases of papilloma, diploidy in 7 and aneuploidy in 3 of 10 cases of grade I diploidy in 4. tetraploidy in 1 and aneuploidy in 6 of 10 cases of grade II , diploidy in 3, tetraploidy in 1 and aneuploidy in 6 10 cases of grade III transitional cell carcinoma. In conclusion, high grade tumors showed more marked augmentation of the oncogene expression and higher incidence of DNA aneuploidy and tetraploidy, suggesting a close relationship among the histopathological grading, oncogene expression and DNA ploidy.