A team of researchers led by Prof. Michael N. Hall from Biozentrum, University of Basel, have discovered a tumour suppressor protein called LHPP. Their paper, published in the science journal Nature and reported on by the University of Basel, describes how LHPP can prevent primary liver cancer cells from uncontrollably proliferating, thereby reducing tumour growth. Scientists have suggested that LHPP could be used as a biomarker for liver cancer, which would have important implications for the diagnosis and prognosis of patients.
Liver cancer is a rare but serious form of cancer that has recently been increasing in incidence, with the number of fatal cases in the U.S. approximately doubling over the last 30 years. It occurs when liver cells mutate and multiply. Although the exact causes are often unknown, it is frequently linked to cirrhosis (scarring or damage) of the liver. Liver cancer produces a range of symptoms that are often difficult to link to the disease, and which usually don’t appear until a late stage. These can include weight loss, vomiting, fatigue, appetite loss, and swelling of the abdomen. The vague nature of these symptoms and their delayed appearance mean that liver cancer is difficult to diagnose and treatment often doesn’t begin until the disease is at an advanced stage. The protein LHPP could therefore play an important role in helping to identify liver cancer at an earlier stage, leading to quicker treatment and a better overall prognosis.
Tumour suppressors, also known as anti-cancer proteins, usually prevent the mutated cell proliferation that causes cancer. However, in cancerous cells the tumour suppressors often do not function correctly. In this recent study, Prof. Hall et al showed a clear link between loss of LHPP, and increased tumour growth and higher mortality rates. Researchers compared over 4,000 proteins between healthy and tumoural liver tissue in mice, leading them to discover the role that LHPP played.
One of the authors of the study, Sravanth Hindupur, says, “It is striking that LHPP is present in healthy tissue and completely absent in tumour tissue.”
The re-introduction of LHPP by researchers prevented tumour growth.