Skip to main content

Research Repository

Advanced Search

Molecular aspects of insulin resistance, cell signaling pathways and breast cancer in relation to obesity.

Weichhaus, M.; Broom, J.; Wahle, K.; Bermano, G.

Authors

M. Weichhaus

J. Broom

K. Wahle



Abstract

A growing number of clinical studies validate a relation of insulin resistance and breast cancer in obese patients. We hypothesised that high plasma insulin levels cause aberrant insulin signalling in breast epithelial cells which may be responsible for an increase in cell proliferation, indicative of potential carcinogenesis and increased cancer progression. It was of particular interest to determine any differences of high insulin concentrations in activating the phosphoinositide-3 kinase (PI-3 kinase) pathway or the mitogen-activated protein kinase (MAP kinase) pathway, the latter being linked to increased cell proliferation. We used two cell line models to investigate the carcinogenic (MCF-10A, immortalised breast epithelial cells) and cancer progression (MDA-MB-231, ER-negative breast cancer cells) potential of insulin. Insulin treatment (100 nM, 24 h) increased cell proliferation in MCF-10A cells, but had no cell proliferative effect on MDA-MB-231 cells. Additionally expression of PCNA as marker of proliferation was tested. The use of PI-3 kinase and MAP kinase specific inhibitors (Wortmannin and PD98059, respectively) demonstrated both pathways being responsible for the observed increase in cell proliferation (MCF-10A). Simultaneous treatment with both inhibitors eliminated insulin induced cell proliferation entirely. Phosphorylation of ERK1/2 was examined as specific activity measurement of MAP kinase pathway. Insulin induced higher phosphorylation levels in MCF-10A cells than in MDA-MB-231. These preliminary results suggest that insulin may initiate carcinogenesis of breast epithelial cells by increasing cell proliferation rather than increasing cancer progression of existing tumours. These effects may be mediated by insulin activating both the PI-3 kinase and the MAP kinase signalling pathways.

Citation

WEICHHAUS, M., BROOM, J., WAHLE, K. and BERMANO, G. 2008. Molecular aspects of insulin resistance, cell signaling pathways and breast cancer in relation to obesity. Presented at 16th European congress on obesity 2008 (ECO 2008), 14-17 May 2008, Geneva, Switzerland.

Presentation Conference Type Poster
Conference Name 16th European congress on obesity 2008 (ECO 2008)
Conference Location Geneva, Switzerland
Start Date May 14, 2008
End Date May 17, 2008
Deposit Date Jul 8, 2021
Publicly Available Date Mar 29, 2024
Keywords Insulin resistance; Breast cancer; Obesity; Increase in cell proliferation; Cancer progression
Public URL https://rgu-repository.worktribe.com/output/1380312
Related Public URLs http://hdl.handle.net/10059/591
https://rgu-repository.worktribe.com/output/1148634
https://rgu-repository.worktribe.com/output/1380321
https://rgu-repository.worktribe.com/output/1380292

Files





Related Outputs



You might also like



Downloadable Citations