Immunohistochemical detection of epidermal growth factor in submandibular gland tumours of mice administered testosterone

Immunohistochemical identification of epidermal growth factor (EGF) is described in experimental carcinoma of the submandibular gland of mice given testosterone before sacrifice. EGF in the submandibular gland was confined to the granular convoluted tubule (GCT) cells, and its level was enhanced following testosterone injection. In the initial phase of carcinogenesis of the gland, degranulation of the GCT cells occurred as well as decreased EGF staining in the degranulated cells. In the testosterone-treated animals, changed GCT cells showed intense EGF deposition. Histological aspects during carcinogenesis in submandibular glands indicated duct-like structures, squamous metaplasia, and squamous cell types of carcinoma with different keratinization. Immunohistochemically detectable EGF was characterized by positive staining in pre-neoplastic or early neoplastic epithelial structures in testosterone-treated mice. However, tumour epithelia did not show any EGF reaction.