Epidermal Hyperplasia and Oral Carcinoma in Mice Overexpressing the Transcription Factor ATF3 in Basal Epithelial Cells

The study investigated the effects of overexpressing the transcription factor ATF3 in basal epithelial cells of transgenic mice. Researchers observed strong nuclear expression of ATF3 in the epidermis, hair follicles, and oral mucosa, leading to hyperplastic changes in hair follicles and mild hyperplasia in the interfollicular epidermis. Although no epidermal tumors were found in the mice over a 16-month period, significant oral mucosal changes were noted, including hyperplasia, dysplasia, and neoplastic lesions such as oral squamous cell carcinoma (60% incidence) and basal cell tumors with follicular differentiation (70% incidence). These findings suggested that ATF3 might have oncogenic properties in epithelial cells, marking the first indication of such a role.