WSU Researchers Discover How a Helpful Protein Can also Cause Cancer

Washington State University researchers have determined how a protein that helps cells fight viruses can also cause genetic mutations that lead to cancer. The research shows how the expression of a protein causes mutations to accumulate in actively replicating DNA.

The lab of Steven Roberts, an assistant professor in the WSU School of Molecular Biosciences, introduced the protein, an enzyme called APOBEC, into a laboratory strain of Saccharomyces cerevisiae. The team then documented how it mutated genetic sequences in a small region of just three nucleotides.

The protein normally kills viruses by changing their genetic sequence, inactivating them. However, the protein can also change the genetic sequence of a normal cell, making mutations that cause cancers. As DNA replicates, it has moments where single strands of the double helix are exposed. The APOBEC protein takes advantage of this vulnerability to cause damage.

The protein can continue to mutate tumor DNA, increasing a cancer's genetic diversity and being able to resist treatment. A greater knowledge of how APOBEC works could lead to treatments that decrease its activity or a treatment creating so many mutations in a tumor that it self-destructs.

For more on the study, read the article on Cell Reports.