Expression of S100P gene in cervical carcinoma cells is not regulated by E7. S100P correlates with and contributes to the tumorigenic capacity of HeLa cells. Inhibition of DNA methylation resulted in induced S100P transcription in CGL1 and Caski but did not change S100P expression in SiHa cells. Suppression subtractive PCR identified differentially expressed genes, including S100P, with possible relevance for control of tumorigenic potential using two cervical carcinoma cell lines of the common HeLa origin, but of different capacity to generate tumors in nude mice. This evidence concerns the gene S100P and cervical carcinoma.