Inhibition of HGF/MET signaling decreases overall tumor burden and blocks malignant conversion in Tpl2-related skin cancer

a WST-1 viability assay for v-rasHa-transduced Tpl2？/？ and WT keratinocytes (RAS) grown in conditioned media from Tpl2？/？ or WT fibroblasts. Results normalized to the v-rasHa-transduced Tpl2+/+ (WT) keratinocyte control. *p？<？0.05, **p？<？0.01. b v-rasHa-transduced WT and Tpl2？/？ keratinocyte malignant conversion in response to fibroblast signaling. v-rasHa-transduced WT (“i”) or Tpl2？/？ (“ii”) keratinocytes cultured in high calcium media develop no foci and remain quiescent in a dispersed monolayer which can be seen at 4X (“iii”) and 40X (“iv”) magnification using rhodamine staining. WT (“v”) and Tpl2？/？ (“vi”) keratinocytes cultured in high calcium fibroblast conditioned media form proliferative foci. Foci from rhodamine-stained cultures stain brightly (“vi”, 4X magnification; “vii”, 40× magnification) under fluorescence microscopy. Real-time PCR quantification of HGF in keratinocytes (c) and immunoblotting (d) of HGF in untreated and v-rasHa-transduced Tpl2？/？ and WT keratinocytes. Immunoblotting of HGF in fibroblasts (e) and immunostaining of HGF in skin (f). Real-time PCR quantification (g) and immunoblotting (h) of p-MET. *p？<？0.0