Protein tied to aggressive breast, lung cancer identified

Low levels of a protein are linked to more aggressive tumours and poorer prognosis in breast and lung cancer patients, a new study has found.
Researchers at the Moffitt Cancer Centre in US found that breast and lung cancer patients who have low levels of the protein called tristetraprolin (TTP) have more aggressive tumours and a poorer prognosis than those with high levels of the protein.
Cancer arises through the increased activity of oncogenes, proteins that drive cancer growth, and the decreased activity of tumour suppressors, proteins that block malignant growth and progression.
TTP is a recently discovered tumour suppressor protein, and scientists at Moffitt have found that this protein can prevent lymphoma growth in mice.

Researchers wanted to further investigate the importance of TTP in cancer patients and what other genes it is associated with in cancer.
Moffitt scientists compared patients who had low levels of TTP to those with high levels of the protein.

They found a network of 50 different genes associated with low levels of TTP in breast, lung and colon tumours.
This genetic network was also present in other tumour types, including prostate, pancreatic and bladder cancer.
This demonstrates that TTP is involved in a variety of mechanisms important for tumour development and growth, and suggests that developing agents that target this network may be an effective therapeutic strategy across a wide spectrum of tumours, researchers said.

They also reported that low levels of TTP were associated with poor prognosis in certain cancers, including a higher rate of relapse in breast cancer patients and lower rates of survival in lung adenocarcinoma patients.
Additionally, breast and lung cancer patients with low levels of TTP tended to have more aggressive types of tumours.
"Identifying this network allows us to set up future research projects focused on understanding how TTP functions as a tumour suppressor with the ultimate goal of developing treatments specific for patients that have low levels of TTP," said Robert Rounbehler, research scientist at Moffitt.
The study was published in the journal PLoS One.