Figure 4.
The reversal of aggravated neoplastic progression in HPV16/Ctsl−/− mice by restoration of epidermal cathepsin L (Ctsl) function. The approach was to restore Ctsl function in Ctsl−/− epidermis by transgenic epithelial expression of human cathepsin V (CTSV; orthologue of mouse Ctsl) under the control of the human keratin 14 (K14) promoter. (a) Immunohistochemical detection of CTSV in a 16-week-old transgenic triple mutant (brown staining; right panel). Bars indicate 50 µm. (b) HPV16 E6 oncogene mRNA expression is not altered by expression of the second K14-promotor transgene (n = 3). (c) Proliferation rates and (d) the frequency of hyperplasia and dysplasia in the epidermis of 16-week-old HPV16/CTSV/Ctsl−/− mice compared with HPV16/Ctsl+/+ and HPV16/Ctsl−/− littermates (n = 10–12). The color reproduction of this figure is available on the html full text version of the manuscript. A full colour version of this figure is available at the Oncogene journal online.