Isolation of Kidney Cancer Cells

Three kidney cancer tissues and corresponding histologically proven non-malignant tissues adjacent to the tumor were obtained after surgery. All the tumors were of Grade 3. Portions of the tissue were immediately sent to the histopathology laboratory for histological diagnosis. Other portions were placed into a transport medium and disaggregated immediately as described previously by Valente et al. [18 (link)]. The cultured cells exhibited the characteristic features of epithelial cells (i.e., positive immunocytochemical staining for cytokeratin 19). Contamination from fibroblasts was quantified using an anti-vimentin antibody (Sigma, St. Louis, MO, USA). Their expression was lower than 10%. In all experiments, to obtain enough cells to perform a basic growth assay and ERK1/2 activation, and to avoid variations in the characteristic features of the cells, normal and corresponding tumor kidney epithelial cells were exclusively used in the primary culture at passage 2.