Figure 1
From: The pluripotency factor NANOG promotes the formation of squamous cell carcinomas
Nanog-inducible mouse model.
(A) Schematic representation of the K5-rtTA;Col1a1::tetO-Nanog mouse model. The reverse transactivator (rtTA) is under the control of the bovine cytokeratin 5 (K5) promoter. A cassette containing the Nanog-cDNA is under the control of the doxycycline (DOX)-responsive promoter (tetO), which was inserted downstream of the Col1a1 locus. Arrows indicate transcriptional start sites. (B) Relative Nanog mRNA levels in the indicated organs determined by qRT-PCR. Nanog-inducible mice (n = 3) containing both transgenes (K5-rtTAtg/.;Col1a1tetO-Nanog/+; abbreviated as TG) and control mice (n = 3) lacking the transactivator (Col1a1tetO-Nanog/+; abbreviated as CTR) were analyzed 48 hr after administration of doxycycline (DOX) (2 mg/ml) in the drinking water. (C) Immunohistochemistry (IHC) for NANOG of paraffin-embedded sections of tail skin from CTR and TG mice treated as indicated in (B). Two magnifications are shown for each tissue (bars correspond to 50 μm). (D) Nanog mRNA levels normalized to Gapdh in CTR and TG tail skin topically treated 4 times, at 48 hr intervals, with 12-O-tetradecanoylphorbol 13-acetate (TPA) or acetone as a control. Mice (n = 4) were exposed to doxycycline (2 mg/ml) in their drinking water 48 hr prior to TPA treatment and throughout the remaining protocol. (E) Epidermal thickness (basal and suprabasal layers) of CTR and TG mice (n = 5) treated as in (D). (F) Representative hematoxylin and eosin (H&E) staining and immunohistochemistry (IHC) for NANOG, Ki67 and LORICRIN of TPA-treated CTR and TG mice as indicated in (D) (bars correspond to 50 μm). Bars in (B, D, E) correspond to mean ± SD of the indicated number of mice (n). Statistical significance was determined by the two-tailed Student’s t test: (*) p < 0.05; (**) p < 0.01.
