Effects of keratinocyte growth factor in the squamous epithelium of the upper aerodigestive tract of normal and irradiated mice

Purpose: To investigate the effects of keratinocyte growth factor (KGF) on the structure of the stratified squamous epithelium of the tongue, buccal mucosa and oesophagus of normal and irradiated mice. Materials and methods: Female BDF1 mice were exposed to total body irradiation from a caesium source. The irradiated mice and normal, unirradiated mice were injected with 5mg/kg per day KGF or vehicle. Thickness and proliferation in the epithelium were measured. Results: KGF caused epithelial thickening of the non-keratinized layers in oral epithelium in normal mice. It increased the number of nucleated layers and influenced differentiation of post-mitotic cells in the upper layers by increasing the size and number of keratohyalin granules, and the number of desmosomes. Single and fractionated doses of radiation caused inhibition of proliferation as detected by markedly reduced BrdU incorporation following exposure, followed by epithelial atrophy. KGF treatment of mice reversed the inhibition of proliferati...