| Abstract: | A malignant human urothelial cell line (J82) has been cultured in a serum-free medium (HMRI-1) developed specifically for normal human urothelium. Unlike the normal human urothelium which grew as an attached monolayer, the J82 cells proliferated as free floating cellular aggregates. Comparative growth kinetic studies have shown that the J82 cells, unlike normal cultured urothelial cells, did not require epidermal growth factor, bovine pituitary extract or transferrin as single additives in the HMRI-1. However, deletion of certain combinations of these factors markedly reduced growth. It was concluded that the J82 cells had a reduced dependency on the normal urothelial cell growth factors suggesting that the J82 cells had altered nutritional requirements which might possibly be associated with the production of autocrine growth factors. |
