192 -- Identification and Classification of Changes in Protein Expression and Localization Associated with Epithelial to Mesenchymal Transitions in Human Vulvar Carcinomas after Exposure to the Glucocorticoid Analog, Clobetasol

It has been well established that decreases in cellular adhesions are associated with progression of squamous cell carcinomas to a malignant state. We have found that clobetasol treatment of A431 cells results in the initial loss of E-cadherin preceded by the gain of vimentin expression. Our system provides an inducible model to study this process. During clobetasol induced EMT in the A431 cells the expression of vimentin increases, but the cells do not lose expression of their cytokeratin molecules. Using Raman spectroscopy, we can identify key changes in metabolites associated with EMT between the A431 cells that respond to clobetasol and those that do not. In addition, we can identify earlier time points indicative of changes induced by clobetasol that lead to EMT. Comparison of the untreated and treated cells using Raman spectroscopy will allow us to identify EMT of the clobetasol treated cells much earlier than we are now capable of doing using detection of E-cadherin and vimentin expression by immunofluorescence microscopy. Ultimately this will aid us in dissecting out the signaling pathway between clobetasol and loss of E-cadherin/gain of vimentin expression as well as identify characteristics that enable some cells to escape clobetasol induced EMT. Comparing the results found from these cells with cells expressing only cytokeratins or vimentin, respectively, can then be used for insight into how each influences the cellular architecture in cases where these subcellular molecules are coexpressed, namely in cells undergoing an epithelial to mesenchymal transition.