Expression of S100P gene in cervical carcinoma cells is independent of E7 human papillomavirus oncogene.

摘要

High-risk human papillomaviruses (HPV) significantly contribute to development of cervical cancer. HPV E7 oncoprotein interferes with the control of cell growth via functional inactivation and/or regulation of multiple molecular targets. Induction of ectopic E7 in breast carcinoma cells has been proposed to decrease transcription of S100P gene, which encodes a calcium-binding protein associated with different types of tumors. We examined a possible relationship between E7 and S100P genes in cervical cell lines. RT-PCR analysis revealed that all HPV-positive cell lines expressed approximately equal levels of E7. Out of them, HeLa, CGL3 and SiHa carcinoma cells as well as HCE16/3 immortalized cells expressed also S100P gene. Inhibition of a DNA methylation by 5-aza-2'-deoxycytidine (5-aza-dC) in S100P-negative cell lines CGL1 and Caski resulted in induced transcription of S100P, but the normal S100P level in SiHa cells was not further increased. Our results suggest that S100P gene expression is independent of E7 in cervical cell lines and that at least in some cases it is subjected to regulation by DNA methylation.