Picture map of Europe with pins indicating European capital cities

Open Access research with a European policy impact...

The Strathprints institutional repository is a digital archive of University of Strathclyde's Open Access research outputs. Strathprints provides access to thousands of Open Access research papers by Strathclyde researchers, including by researchers from the European Policies Research Centre (EPRC).

EPRC is a leading institute in Europe for comparative research on public policy, with a particular focus on regional development policies. Spanning 30 European countries, EPRC research programmes have a strong emphasis on applied research and knowledge exchange, including the provision of policy advice to EU institutions and national and sub-national government authorities throughout Europe.

Explore research outputs by the European Policies Research Centre...

Indoleamine 2,3-dioxygenase activity and L-tryptophan transport in human breast cancer cells

Travers, M. and Gow, Iain F. and Barber, M.C. and Thomson, Jean and Shennan, David B. (2004) Indoleamine 2,3-dioxygenase activity and L-tryptophan transport in human breast cancer cells. BBA - Biomembranes, 1661 (1). pp. 106-112. ISSN 0005-2736

Full text not available in this repository. Request a copy from the Strathclyde author

Abstract

The activity and expression of indoleamine 2,3-dioxygenase together with -tryptophan transport has been examined in cultured human breast cancer cells. MDA-MB-231 but not MCF-7 cells expressed mRNA for indoleamine 2,3-dioxygenase. Kynurenine production by MDA-MB-231 cells, which was taken as a measure of enzyme activity, was markedly stimulated by interferon-γ (1000 units/ml). Accordingly, -tryptophan utilization by MDA-MB-231 cells was enhanced by interferon-γ. 1-Methyl- -tryptophan (1 mM) inhibited interferon-γ induced kynurenine production by MBA-MB-231 cells. Kynurenine production by MCF-7 cells remained at basal levels when cultured in the presence of interferon-γ. -Tryptophan transport into MDA-MB-231 cells was via a Na+-independent, BCH-sensitive pathway. It appears that system L (LAT1/CD98) may be the only pathway for -tryptophan transport into these cells. 1-Methyl- , -tryptophan trans-stimulated -tryptophan efflux from MDA-MB-231 cells and thus appears to be a transported substrate of system L. The results suggest that system L plays an important role in providing indoleamine-2,3-dioxygenase with its main substrate, -tryptophan, and suggest a mechanism by which estrogen receptor-negative breast cancer cells may evade the attention of the immune system.