Extracellular matrix components produced by SV40-transformed human epidermal keratinocytes.

The production of fibronectin, laminin and glycosaminoglycans (GAGs) has been investigated in normal and SV40-transformed human epidermal keratinocytes. Normal keratinocytes produced small amounts of laminin and fibronectin and three classes of GAGs; hyaluronic acid, heparan sulphate and chondroitin sulphate, hyaluronic acid being the major GAG. The SV40-transformed keratinocytes retained their cell-surface laminin and fibronectin, and in some cases showed elevated levels when compared to normal keratinocytes. All the transformants showed a shift in GAG production from hyaluronic acid to heparan sulphate, so that in all SV40-transformed keratinocytes heparan sulphate was the major GAG. These results demonstrate that the loss of extracellular matrix, which normally occurs in transformed fibroblastic cells, is not a feature of SV40-transformed human keratinocytes.