Microarray analysis of cultured gastric myofibroblasts

Neuronal, endocrine and exocrine cells exhibit regulated exocytosis but there is also a body of evidence for regulated exocytosis from other cell types. Myofibroblasts are a stromal cell type that secretes extracellular matrix proteins, growth factors and cytokines; they are important in wound healing and increasingly are recognised to play a role in modifying the cellular microenvironment in cancer. We have established calcium dependent regulated secretion in a subset of myofibroblasts from gastric cancers, adjacent tissue and from normal tissue. We have used microarrays to look for the expression of genes associated with the regulated secretory phenotype. A panel of different myofibroblast lines generated from gastric cancers, adjacent tissue, and normal tissue, were assayed for the ability to exhibit regulated exocytosis in response to acute stimulation with IGF. From this database lines were designated as either “responders” or “non-responders” ie exhibited a regulated exocytosis phenotype, or not. The transcript profiles of the two classes of cell were examined using Affimetrix microarrays.