抄録
RL34 cell line was established from liver epithelium of young normal Wistar rat in 1976 and SGE1 cell line was established from renal glomerular epithelium of young normal Wistar rat in 1987 by us. By the tumorigenicity assays, both RL34 and SGE1 cells did not show any sign of malignant transformation and a majority of the cells were revealed in a near-diploid range. It has been reported that some of the spontaneously immortalized mammalian cell lines have mutant tumor suppressor genes. In the present study, expression of p53 protein in both RL34 and SGE1 cell lines was immunocytochemically analyzed by monoclonal anti-p53 antibodies. Furthermore, mutations of p53 gene were analyzed by restriction enzyme digestion of PCR fragments and sequencing. The results indicated that both cell lines expressed mutated p53 proteins. The mutation of p53 gene in RL34 cell line was on 3'splicing signal portion of intron 4. These findings suggest that p53 gene mutations may be related to immortalization of RL34 and SGE1 lines.
