New skin cancer gene, new treatment
The discovery of a gene linked to skin cancer in zebrafish could lead to new treatments for the disease. The gene, called SETDB1, is thought to work alongside another known cancer causing gene called BRAF.
Cancers formed from skin pigment cells, called melanomas, were previously linked to the BRAF gene in 2002. It was found that four fifths of human melanomas have a mutation in this gene.
The BRAF gene causes skin pigment cells in the fish to become larger, darker and often cancerous. However, benign splotches can also have the BRAF mutation, suggesting the cancer is dependent on other genes as well. Screening more than 3000 fish, researchers found that the SETDB1 gene accelerates melanomas, causing them to grow sooner and faster. The gene was also found to be more active in two thirds of human melanomas.
It is thought to release an enzyme that boosts the activity of other growth promoting genes linked to cancer. In a second study, researchers found combinations of over 100 genes that are linked to the development of melanomas. These genes are associated with stem cells called embryonic neural crest cells. It is thought that extra stem cells could lead to melanomas.
Researchers were able to target these neural crest cells using an existing medicine for arthritis, called, leflunomide. Combining leflunomide with another medicine to reduce the activity of the BRAF gene, researchers were successful in treating melanomas in mice. The combination of medicines removed the tumour almost completely in two fifths of the mice.
Read more about animals in cancer research here.