'Double Agent' Protein Presents Potential Cancer Treatment Target

A protein that aids in cancer growth and contributes to higher mortality in breast cancer may be a potential target for future therapies.

The protein GlyRS has been found to play a role in protein synthesis, but a study published in Nature Structural & Molecular Biology showed the protein can act as a double agent. In addition to the essential role of GlyRS in creating proteins, it also helps further modify proteins that cause cancer growth, according to the study.

“We have potentially found an important target for anti-cancer treatment,” said study lead Xiang-Lei Yang.

Researchers found that when GlyRS is overexpressed, it may lead to the under expression of the protein p27. Furthermore, GlyRS creates a protective shield around the modifier protein NEDD8, which safely chaperones it to meet the target protein cullin.

Once NEDD8 is in place, cullin becomes activated to degrade p27. When kept at correct levels, the p27 protein begins to regulate the cell cycle, putting a stop to potential cancer growth.

However, when GlyRS levels increase, an overabundance of p27 proteins are degraded and cells begin to multiply unchecked.

“Cancer cells hijack and over exaggerate the system,” said first study author Zhongying Mo. “This can lead to tumorigenesis.”

Researchers noted this process is especially dangerous due to the role of GlyRS in protein synthesis, which provides cancers with the proteins needed to continue growing.

“Ultimately, both functions are linked to cell proliferation and tumorigenesis,” Yang said.

When researchers analyzed data from a breast cancer database, they found patients with increased levels of GlyRS had higher mortality.

Future research will study the effect of GlyRS in different types of cancers and also the potential development of GlyRS inhibitors.