The expression of the H19 gene and its function in human bladder carcinomacell lines

The human H19 gene is a paternally imprinted oncofetal gene, highly express ed in several fetal tissues, downregulated in nearly ail adult tissues but re-expressed in carcinomas of tissues which express the gene in fetal life. It has no known protein product and till today, no function could be desig nated to H19 RNA. Cells derived from bladder carcinomas and hepatocellular carcinomas were transfected with plasmids carrying a luciferase reporter ge ne under the control of a 800 nucleotides long promoter region of the H19 g ene either alone or together with different parts of a 5 kb downstream regi on, previously shown to possess enhancer activity. Our results provide evid ence that three regions of the 3' downstream sequence can independently sti mulate the H19 promoter activity in a tissue and cell specific manner, The growth rate of two cell populations, both derived from the same bladder car cinoma cell line and which differ in their H19 RNA content, were compared. The cells with a high H19 RNA level stopped their proliferation after 48 h when cultivated in a low serum containing media while the cells lacking H19 RNA continued their proliferation for at least an additional 48 h period. (C) 1999 Federation of European Biochemical Societies.