Caveolin-1 and Flotillin-1 Differential Expression in Clinical Samples of Renal Cell Carcinoma

Caveolin-1 and flotillin-1 belong to plasma membrane microdomains. They are characterized by peculiar lipid and protein composition and are involved in fundamental cellular events such as: signal transduction, cell adhesion, lipid/protein sorting, and human cancer. We addressed caveolin-1 and flotillin-1 expression in 30 human renal cell carcinoma (RCC) and adjacent normal kidney (ANK) samples by SDS-PAGE and immunoblotting with specific antibodies. Significant caveolin-1 and flotillin-1 over-expression was found in RCC tissues compared to ANK, and was confirmed by immunohistochemistry. Caveolin-1 and flotillin-1 protein levels were found by 1-D, 2-DE, and MS to be increased also in RCC microdomain-enriched subcellular fractions purified from paired RCC and ANK samples.