Gene known to protect against cancer can also promote tumor growth

Researchers at the Spanish National Cancer Research Centre have discovered a gene that can simultaneously protect against cancer and favor its growth. The team wished to ascertain whether the tumor-protective effect of Chk1 was magnified in organisms with a larger quantity of the protein it codes for, so they created a mouse with three copies of the gene instead of the normal two. They then extracted and cultured the animal's cells and turned them cancerous with the aid of other genes. What they observed confounded all expectations: the cells became malignant more easily when carrying an extra copy of Chk1. The reason for this paradox is that Chk1 has a beneficial effect on healthy cells, but also benefits tumor cells once they have established themselves in the body.