Expression of Immediate Early Transcription Factors in Human Renal Cell Tumors

Abstract

Initiation and progression of malignant growth is a multistep process. Various genes are likely to play potential roles in this process, of which cellular oncogenes and suppressor genes have recently been the focus of investigation. Cellular oncogenes are involved in the regulation of normal growth and/or differentiation and in the signal transduction pathway or in the transcriptional regulation of gene expression of diverse cellular genes. Transcription factors, representing proteins that regulate gene expression by binding to specific regulatory DNA sequences, have been implicated in oncogenesis since structural or functional changes in these factors may result in an altered expression of multiple genes, subsequently leading to changes in both growth properties and differentiation state of affected cells. The transcription factors c-fos, c-jun, and early response gene (EGR-1) are members of a class of proto-oncogenes known as immediate early genes. Genes belonging to this class are characterized by their mRNA levels being strongly induced by serum stimulation: within 20 min after serum stimulation of serum-starved 3T3 cells the mRNA levels of these genes are induced 40- to 50-fold. To date, little is known about the expression of these genes in primary human renal cell carcinomas [1].