[Papillomaviruses pathogenic to human and their relationship to oncogenesis].

In recent times, modern gene technology has led to a new understanding of the role of the human papillomaviruses in the development of some malignant tumours in humans. As a result, models based on molecular-biological analysis of the interactions between papillomaviruses and tumour cells have been developed. Cancer appears to be the result of inadequate control of the host cell over persisting viral genes. Virus infection is the necessary precondition for malignancy, but it is not sufficient to trigger the growth of a tumour. This can only occur if the cellular control genes are impaired possibly as the result of a mutagenic effect of simultaneous factors such as recurrent infections, UV radiation, X-rays, or chemical carcinogens.