Squamous cell carcinoma of the uterine cervix is one of the most common cancers among women. Correlation between human papilloma virus (HPV) infection of the uterine cervix and the development of cervical neoplasia has been established. More recent studies have shown the presence and expression of integrated HPV types 16 and 18 DNA sequences in 70-80% of cervical tumours and tumour cell lines. It has been suggested that, in addition to HPVs, other agents such as hormones and tobacco products act as cofactors in cervical neoplasia (for review see ref. 15). The presence and expression of a glucocorticoid-responsive element in HPV-16 has been reported. Here we provide evidence for the oncogenic transformation of primary cells with a combination of HPV-16 DNA, but not HPV-11 DNA, and the activated form of the human Ha-ras oncogene only in the presence of the glucocorticoid hormone dexamethasone.