GLUCOCORTICOID REQUIREMENT FOR GROWTH OF HUMAN PAPILLOMAVIRUS 16-TRANSFORMED PRIMARY RAT-KIDNEY EPITHELIAL-CELLS - CORRELATION OF DEVELOPMENT OF HORMONE RESISTANCE WITH VIRAL-RNA EXPRESSION AND PROCESSING

The establishment of transformation of primary baby rat kidney epithel ial cells by human papillomavirus type 16 DNA requires glucocorticoid hormones (Pater et al., Nature (Lond.), 335: 832-835, 1988). In this r eport we provide evidence that growth of transformed baby rat kidney c ells in culture also requires glucocorticoids. However, transformed ce lls for which growth does not require hormone readily arise after a br ief period of crisis, if cultured without added hormone. No reduction of glucocorticoid receptor was evident in non-hormone-requiring cells. The expression of human papillomavirus 16 RNA in these cells was anal yzed by Northern blot, primer extension, and RNase protection analysis . Cells that do not require hormone had greatly reduced levels of tran scripts initiated from the viral P97 promoter. However, there is evide nce for compensating alterations to allow more efficient expression of E7 mRNA, since the growth of these cells is correlated with altered p atterns of viral RNA expression and processing.