This paper demonstrates that Y79 human retinoblastoma cells contain immunoreactive insulin (IRI) and release it in the medium. Cells cultured either in suspension or in monolayer showed a similar content of IRI. Moreover, in both conditions, IRI concentration was higher in cells cultured in serum-supplemented medium rather than in serum-free medium. Retinoblastoma cells are capable of synthesizing insulin. This was demonstrated by incubating Y79 cells with [3H]leucine. The synthesized radioactive insulin was separated and assayed by means of a HPLC procedure described in this paper. Both cell growth and [3H]thymidine and [3H]uridine incorporation into acid-insoluble fraction was reduced (-75%) in Y79 cells cultured without serum with respect to those cultured in the presence of serum. The addition of insulin to the serum-free medium stimulated both cell division and DNA and RNA labeling, with values approaching those obtained with serum supplemented cultures. Insulin-like growth factor I exerted similar effects, but at a much lower concentration than insulin. We suggest that both insulin and IGF-I may represent mitogenic signals for these cells which might be mediated through insulin-like growth factor I receptors.
|Data di pubblicazione:||1994|
|Titolo:||Synthesis of insulin and its effects in Y79 human retinoblastoma cells|
|Autori:||Vento, R.; Tesoriere, G.; Giuliano, M.; Calvaruso, G.; Lauricella, M.; Carabillo, M.|
|Tipologia:||Articolo su rivista|
|Citazione:||Vento, R., Tesoriere, G., Giuliano, M., Calvaruso, G., Lauricella, M., & Carabillo, M. (1994). Synthesis of insulin and its effects in Y79 human retinoblastoma cells. EXPERIMENTAL EYE RESEARCH, 59.|
|Tipo:||Articolo in rivista|
|Appare nelle tipologie:||01 - Articolo su rivista|