FIG. 9.
Transcriptional regulation of INK4 family genes by progestins. Ten micrograms of total RNA from T-47D cells treated with ORG 2058 or vehicle at various time points was subjected to RNase protection analysis using a template set focused on cell cycle inhibitors according to the manufacturer's instructions (hCC-2; Pharmingen). Protected fragments corresponding to mRNA encoding p18INK4c, p27Kip1, and p19INK4d are shown in comparison with the fragment encoding the metabolic enzyme GAPDH as a control for RNA loading. (B) Densitometric values for levels of mRNA encoding p18INK4c are expressed as a percentage of averaged control values. The values for 6, 12, 18, and 24 h represent averages of two independent experiments.