Scientists discover gene that causes rare cancer
European scientists have identified a gene behind a rare form of cancer called adenoid cystic carcinoma (ACC). The team hope their discovery will lead to new tests and treatments for the disease. Their findings are published in the journal Proceedings of the National Academy of Sciences (PNAS). ACC is an extremely rare condition. It occurs in over 30 organs of the body, with most cases (58%) being found in the head and neck region; the salivary glands alone account for 34% of cases. A further 17% of cases are found in the respiratory system, 12% occur in the breast and the remaining 13% are found elsewhere in the body. Although it grows slowly, ACC eventually proves fatal in the majority of cases; 80% to 90% of patients with ACC in the head and neck die within 10 to 15 years of diagnosis. Overall, the 15-year survival rate stands at around 40%; ACC is treated with surgery followed by radiation. In this study, scientists in the Netherlands and Sweden reveal that ACC is caused by a fusion gene, which arises when two healthy genes fuse together. They arrived at this conclusion after studying tissue samples from ACC tumours taken from different parts of the body. The fact that all ACCs analysed displayed the fusion gene, irrespective of whether they came from the salivary glands, breast or elsewhere, indicates that it is a hallmark of the disease, the team explained. The two genes that make up the fusion gene are MYB and NFIB. MYB has a number of functions in the body; as well as controlling cell growth, it helps to trigger the death of cells that are no longer needed. Normally, the activity of MYB is suppressed in more mature cells. The researchers suggest that when MYB fuses with NFIB, the cell loses its ability to control MYB's activity. As a result, it becomes active, resulting in the massive overproduction of an abnormal protein with cancer-causing properties. 'We suggested back in 1986 that the MYB gene might be involved in this form of cancer, but it's only recently that we've had access to the tools needed to prove it,' commented Professor Göran Stenman of the Lundberg Laboratory for Cancer Research at the University of Gothenburg in Sweden. 'Now that we know what the cancer is down to, we can also develop new and more effective treatments for this often highly malignant and insidious form of cancer. One possibility might be to develop a drug that quite simply turns off this gene.' The research also sheds new light on the role of fusion genes in cancer. 'Previously it was thought that fusion genes pretty much only caused leukaemia, but our group can now show that this type of cancer gene is also common in glandular cancer,' explained Professor Stenman. 'This is an important discovery, because it's a new mechanism which I think will turn out to be quite common in a variety of human cancers.'
Countries
Netherlands, Sweden