Fish offer clues on deadly liver cancer
The commonest type of liver cancer, hepatocellular carcinoma (HCC), is a leading cause of deaths related to the disease worldwide. Researchers have now used fish to collect new information that might help diagnose and treat it.
Although there are several treatment options available, they are largely unsuccessful because the disease is so poorly understood. Clinical studies of patients with HCC, combined with studies using mice and other animal models, have provided some clues but many questions about how to diagnose and treat this deadly form of cancer remain.
Zhiyuan Gong and Serguei Parinov from the National University of Singapore decided to pursue these questions using zebrafish as a model system, reports the journal Disease Models and Mechanisms. Their study uncovers new information that might help diagnose and treat HCC in humans, and shows that zebrafish are a powerful and cost-effective model to study liver cancer, according to a National University statement.
Previous work indicated that cancer cells from patients with HCC always have abnormally high activation of a cellular pathway called Ras. However, whether and how the Ras pathway actually causes liver cancer was not clear. To focus in on this issue, Gong and Parinov created genetically engineered zebrafish to express a cancer-causing form of Ras (krasV12) in the liver.
Fish having the highest expression of krasV12 died rapidly of malignant liver cancer (mostly within 30 days), whereas fish with lower krasV12 expression survived longer and did not develop full-blown disease.