DNA vaccines against HPV-16 E7-expressing tumour cells.

Background: Genetic immunisation induces the endogenous production of the encoded antigens, which favours their presentation by MHC class I molecules. The E7 protein from "high risk" Human Papillomavirus (HPV) is constitutively expressed in cervical cancer and represents a target for immunotherapy.

Materials And Methods: Several E7-encoding DNA vaccines were constructed including unmodified E7 and E7 fused to ubiquitin or to the Invariant chain in order to increase the presentation of E7-derived peptides by MHC class I or II molecules, respectively.

Endothelin receptor blockade inhibits the growth of human papillomavirus-associated cervical carcinoma.

Human papillomaviruses (HPVs) are associated with cervical cancer and interact with growth factors that may enhance malignant transformation of cervical carcinoma cells. Endothelin-1 (ET-1) is released from HPV-transfected keratinocytes and induces increased growth response in these cell lines in comparison with normal cells. HPV-positive cancer cells secrete ET-1 and express mRNA for ET-1 and its receptors, whereas HPV-negative carcinoma cell lines express only the ET(B) receptor (ET(B)R) mRNA and do not secrete ET-1.