ADENOSINE AS AN ENVIRONMENTAL STRESSOR AFFECTING HSP27 AND CXCR4 IN EPITHELIAL CELLS

Abstract

Solid tumours are a hostile tissue environment in which the cells are exposed to many stresses including hypoxia. One consequence of hypoxic conditions is an increase in extracellular levels of the purine nucleoside adenosine, which enhances tumour cell migration. This is achieved in part through an increase in the levels of the chemokine receptor CXCR4, which along with its ligand CXCL12, is a key player in breast cancer metastasis. The cellular response to stress is mediated by a family of proteins known as heat-shock proteins (HSPs). The small heat shock protein 27 (HSP27) has been implicated in changes in cancer cell migration. I have therefore studied the regulation of HSP27 in human breast cancer cells by conditions that normally exist in the stressful tumor environment. My project specifically aimed to establish whether changes in HSP27 are linked to hypoxia, adenosine levels and alterations in the CXCL12-CXCR4 migratory pathway.