FIG. 9.

Effect of inhibitors of posttranslational protein processing on RCC cells. Parental (solid bars) and wtVHL-expressing (hatched bars) UMR, 786, and 121 cells, were plated at a density of 30,000 cells/well in 6-well cluster plates and cultured for 48 h in complete medium, either alone or supplemented with tunicamycin (A) or a variety of drug treatments affecting protein processing: glucosamine (10 mM), 2-deoxyglucose (10 mM), azetidine (3 mM), brefeldin A (0.3 μg/ml) and thapsigargin (3 μM) (B), with the exception of UMR cells, which were treated with 2-deoxyglucose (10 mM) for 72 h. At the end of each treatment period, cultures were subjected to clonogenic assay as described in Materials and Methods. Percentages were calculated relative to untreated, time-matched controls. Dimethyl sulfoxide alone had no influence on clonogenicity relative to untreated cells. Treatments were done in duplicate, and the values represent the mean ± the SEM for at least three independent experiments.