Primary Cell Cultures Arising from Normal Kidney and Renal Cell Carcinoma Retain the Proteomic Profile of Corresponding Tissues

Abstract
Renal cell carcinoma (RCC) tissue is composed of a mixture of neoplastic and normal cells, which complicate proteome analysis. The aim of our study was to investigate whether it is feasible to establish primary cell cultures of RCC and of renal cortex maintaining the tissue phenotype along with a more homogeneous and enriched cytological material. Fourteen (82.3%) primary cultures from 17 surgical cases were established and characterized by morphology, growth rate, immunocytochemistry, and molecular analysis performed by Real-time PCR, Western blotting, two-dimensional electrophoresis (2-DE), and mass spectrometry. Cultures showed >90% cytokeratine-positive epithelial cells. In primary tumor cultures, the molecular phenotype of manganese superoxide dismutase and heat shock protein 27 was the same as that found in tumor tissues with overexpression and increased number of isoforms. Moreover, 27 out 28 specific proteins and their isoforms, present in spots excised from 2-DE gel of cortex or RCC cultures, corresponded to those identified on the 2-DE tissue cortex reference map, suggesting that these primary cultures retain the proteomic profile of the corresponding tissues. Keywords: renal cell carcinoma • primary cultures • proteome • real-time PCR • two-dimensional gel electrophoresis • mass spectrometry • Western blotting • immunocytochemistry • manganese superoxide dismutase • heat shock protein 27