PROGRESS OF FUNDAMENTAL RESEARCH IN WILMS-TUMOR

The progress of fundamental research on the histopathological and mole cular genetic properties, model systems, growth factor involvement, an d tumor markers of clinical nephroblastoma (Wilms' tumor) are reviewed . Histologically, Wilms' tumor (WT) has been found to reveal a disorga nized renal developmental process in which blastema and epithelia are randomly interspersed in varying amounts of stroma. Anaplasia is the o nly criterion for assigning a WT as having an ''unfavorable histology. '' Cytogenetic analysis identified WT genes at chromosome 11p13 (WT1), 11p15 region (WT2), and 16q (WT3). Permanent in vitro WT cell lines a nd in vivo WT models, such as human xenografts, have been established which provide indefinite sources of tumor material for fundamental, as well as therapy-directed, research. Abnormalities of growth factor (G F) expression in WT indicate that GF may play an important role in WT pathogenesis. A series of monoclonal antibodies was tested in WT by im munohistochemical techniques to identify specific diagnostic and progn ostic markers. p53 expression in anaplastic WT is significantly higher than in differentiated WTs, indicating p53 may be a prognostic marker . Although significant progress has been made in the fundamental resea rch, our basic knowledge of this malignancy is still limited. The avai lability of suitable experimental models, particularly the human xenog raft system, offers the opportunity for further study of the cell biol ogical and molecular aspects of WT and its clinical progression.