BMI1 and squamous cell carcinoma: Furthermore, increased BMI-1 expression was found in bronchial premalignant lesions as well as squamous cell carcinoma (SCC), indicating that its expression in neoplastic cells may be an early event in lung carcinogenesis.13 BMI-1 is also overexpressed in OSCC cells when compared with normal oral mucosa cells and has been presumed to influence proliferation and immortalization of epithelial cells in oral carcinogenesis.14