An analysis of more than 4,000 tumours from 19 different cancer types assesses the role of viruses in causing the disease. The work, published this week in Nature Communications, provides a comprehensive dataset for understanding the role of viruses in tumour formation.
Erik Larsson and colleagues used data from The Cancer Genome Atlas to detect the presence of viral nucleic acids in 4,438 tumours from 19 different cancer subtypes and found that 178 tumours contained viral RNA. They confirmed the presence of human papillomavirus in cervical cancer and also hepatitis virus B in hepatocellular (liver) cancer. However, they did not detect the presence of viruses in breast cancer or glioblastoma multiforme (cancer of the brain), both of which have been suggested to have a viral cause. The data covers a diverse set of tumours including those from bladder, colon, brain, kidney, skin, ovary prostate, thyroid, rectum and lung. They find that 7.3% of bladder, 9.8% of colon and 14.8% of head and neck, and 5.6% of rectal cancers contain the presence of viral RNA, implying that virsuses may have a role in a small fraction of these tumours.
These findings provide the largest analysis of viruses in tumours and preclude a broad spectrum role of viruses in tumour formation.