The TGFβ pathway is less active in K14 cKO keratinocytes. (A) Isolated keratinocytes were treated with or without TGFβ for 18 h and subsequently tested via qPCR for the cell cycle inhibitors p15, p21, and p27. Only WT cells showed significant induction of the inhibitors after TGFβ stimulation (n = 4 to 9). (B) Western blotting of wound lysates from WT and cKO mice 5 days after wounding for inactive MT1MMP (pro-MT1MMP) and activated MT1MMP (Act-MT1MMP). cKO mouse wounds contained more inactive MT1MMP but significantly less of the active form than WT mouse wounds (n = 4). Results are given as means ± SEMs *, P < 0.05; **, P < 0.01; N.S., not significant.