Insulin-like growth factors I and II induce cell death in Wilms's tumour cells

M Granérus¹, A Johannisson¹, P Ekblom² and W Engström¹

¹ Department of Pathology, Faculty of Veterinary Medicine, Swedish University of Agricultural Sciences, PO Box 7028, S-750 07 Uppsala, Sweden
² Department of Animal Physiology, University of Uppsala, BMC, S-75124 Uppsala, Sweden

Correspondence to:
Dr Engströmwilhelm.engstrom{at}pat.slu.se

Aim—To study the effects of insulin-like growth factors (IGFs) on the growth phenotype of a Wilms's tumour cell line (WCCS-1).

Methods—WCCS-1 cells were cultured in vitro and exposed to IGF-I and IGF-II, as well as their antagonists, IGF binding protein 2 and the type I receptor blocking antibody IGF-IR. The effects on proliferation and cell cycle parameters were assayed by assessing cell numbers, autoradiography after labelling with tritiated thymidine, and flow cytometry after double staining with fluorescein isothiocyanate (FITC) labelled annexin V and propidium iodide.

Results—The addition of IGF-I as well as IGF-II in physiological doses induced cell death in Wilms's tumour cells. Cell numbers decreased most dramatically on the fifth to sixth day after growth factor addition. The occurrence of apoptosis as well as necrosis was confirmed by annexin-V staining of cell cultures. S-phase indices were comparable, irrespective of whether the cells were exposed to IGFs or not, which suggests that WCCS-1 cells undergo cell death at random during the cell cycle rather that from the prereplicative phase. To exclude any influences of the IGF binding proteins (IGFBPs), all results were repeated with Des(1-3)IGF-I, which is unable to bind to any of the IGFBPs. However, this peptide was equally potent in inducing cell death. Finally, the addition of IGFBP-2 or the type 1 receptor blocking antibody IGF-IR partly abrogated the death inducing effects of IGF-I and IGF-II.

Conclusions—Insulin like growth factors induce cell death—apoptosis as well as necrosis—in cultured Wilms's tumour cells. Furthermore, it is proposed that this effect is mediated by the type 1 receptor.

Key Words: insulin-like growth factor I • insulin-like growth factor II • Wilms's tumour • apoptosis

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

• Huang, C.-C., Gadd, S., Breslow, N., Cutcliffe, C., Sredni, S. T., Helenowski, I. B., Dome, J. S., Grundy, P. E., Green, D. M., Fritsch, M. K., Perlman, E. J. (2009). Predicting Relapse in Favorable Histology Wilms Tumor Using Gene Expression Analysis: A Report from the Renal Tumor Committee of the Children's Oncology Group. Clin. Cancer Res. 15: 1770-1778 [Abstract] [Full Text]  
• Remacle-Bonnet, M., Garrouste, F., Baillat, G., Andre, F., Marvaldi, J., Pommier, G. (2005). Membrane Rafts Segregate Pro- from Anti-Apoptotic Insulin-Like Growth Factor-I Receptor Signaling in Colon Carcinoma Cells Stimulated by Members of the Tumor Necrosis Factor Superfamily. Am. J. Pathol. 167: 761-773 [Abstract] [Full Text]