are cancers caused by viruses
View full size image. Viruses may be causing more cancers than previously thought, according to a new study. Scientists know that a few cancers, such as cervical cancer, are caused by viruses, because researchers have isolated the viral genomes from the cancerous cells. But some viruses may take a hit and run approach â inducing cancer and then vanishing before the disease is caught, the researchers say.
The region of the viral genome (DNA in DNA tumor-viruses or RNA in RNA-tumor viruses) that can cause a tumor is called an oncogene. This foreign gene can be carried into a cell by the virus and cause the host cell to take on new properties.