Publication List English
2021/10/31
Generation of a Transgenic Zebrafish Line for In Vivo Assessment of Hepatic Apoptosis
2021/07/09
Quality Control Protocol for Zebrafish Developmental Toxicity Studies
》Loss of nuclear localization of the S100C protein in immortalized human fibroblasts.
2001/01/01
M Sakaguchi,H Yamada,T Tsuji,Y Inoue, M Miyazaki,T Tanaka,M Namba
RADIATION RESEARCH 155,208 -214 2001
Abstract
It is well known that cancer develops through a multistep process. In vitro transformation studies of normal human cells have shown that the immortalization step is critical for neoplastic transformation of cells. Furthermore, studies of cell fusion between normal and immortalized cells have indicated that the normal phenotype is dominant and the immortal phenotype is recessive. Thus we looked for cellular proteins that were down-regulated in immortalized human cells by two-dimensional gel electrophoresis to elucidate the mechanisms of immortalization of human cells. We found that the S100C protein was down-regulated in immortalized cells. This protein was localized in the cytoplasm of cells at the semiconfluent stage, while at the confluent stage it moved into the nuclei of normal cells but not into those of immortalized cells. Microinjection of an S100C antibody into normal confluent cells diminished the level of nuclear S100C protein, resulting in DNA synthesis. Taken together, loss of nuclear localization of the S100C protein, which may be related to DNA synthesis, is thought to be one of the mechanisms of immortalization.