Protein inhibitor may help cure liver cancer

Chinese scientists have identified a protein that causes the proliferation of liver cancer cells, which could assist in the development of a new cancer drug.

By studying proteins of patients with early-stage liver cancer, researchers found that the activity of one protein, identified as SOAT1, can affect cholesterol stability in cancer cells - which triggers them to proliferate and migrate.

The study also found that avasimibe, an inhibitor of SOAT1, shows potential as a targeted therapeutic drug.

The paper, co-authored by scientists from the Academy of Military Medical Sciences, Zhongshan Hospital affiliated to Fudan University, and Beijing Cancer Hospital, was recently published in Nature.

Fan Jia, dean of Zhongshan Hospital affiliated to Fudan University, said doctors often found from clinical practice that even a very small tumor can recur and deteriorate quickly after being removed. They suspected it might have nothing to do with the size of the tumor, and instead be related to its biological behavior.

"This study explains why very early liver cancer can still spread to the entire body one to three months after surgery," he said.

"It is of great value for future drug research, and helps explain the biological features of liver cancer so that more effective treatment can be selected."

Liver cancer is one of the most common malignant tumors in China. Among 700,000 cases of liver cancer worldwide each year, 350,000 are in China, said Jiang Ying, the paper's first author and also a researcher at the Academy of Military Medical Sciences.

The current globally recognized clinical plan holds that liver cancer can be completely cured if caught at an early stage, but years of clinical practice have found that the disease recurs in 50 to 70 percent of primary liver cancer patients.

"So how to accurately treat this particular group of patients is a problem that the entire world is now facing," Jiang said.

She said now that avasimibe has been found to be effective, the researchers will focus on developing a drug using it.

There have been previous studies on avasimibe, but they were focused on its efficacy in lowering blood lipids, Jiang said. Though they ended in failure, the drug was clinically confirmed to be safe, which will help greatly reduce the time for new anti-cancer drug development, she said.

The study is part of the Chinese Human Proteome Project, launched in 2014 to explore new approaches to treat major endemic diseases by building up human proteome biological profiles and mapping all the proteins in major organs.

It is also a collaborative effort of the international Human Proteome Project, organized by the Human Proteome Organization, that aims to enhance the understanding of human biology at the cellular level by mapping the entire human proteome - the range of proteins that can be expressed by genes.

He Fuchu, an academician at the Chinese Academy of Sciences and the chief scientist of the Chinese Human Proteome Project, said China embarked on proteomics in 1998 and also initiated the human liver proteome project in 2002.

The country has been an important contributor to international proteomics development, and the new finding helps open doors to new research methods, he said.