Human genital cancer: synergism between two virus infections or synergism between a virus infection and initiating events?

It is proposed that human genital cancer results from a "promoting" papillomavirus infection and initiating events, frequently caused by herpes simplex virus (HSV) infections. This hypothesis is based on the demonstration of DNA from different types of papillomaviruses in some cervical cancer biopsy samples and in premalignant lesions; on studies revealing the initiator-like functions of HSV infections; and on analogous interactions of papillomavirus infections with initiators in the induction of certain animal and human carcinomas. The model reconciles seroepidemiological data linking HSV to human genital cancer with the apparent difficulties in finding HSV DNA by biopsy in genital cancer.