LOS ANGELES (CNS) - A Cedars-Sinai scientific team has been awarded a $9.1 million grant by the National Cancer Institute to study how fat may promote cancer's spread to the liver, the medical center announced today.
he research team will focus on the interplay between dietary fat and fatty liver disease -- which is commonly associated with obesity -- and the mechanisms that allow cancer to spread, or metastasize, to the liver, according to Cedars.
The liver is the second-most common site, after lymph nodes, to which cancer spreads. The majority of patients that die of pancreatic, colon or prostate cancer develop liver metastases at the time of death, said co-lead investigator Dr. Neil Bhowmick, director of the Cancer Biology Program at Cedars-Sinai.
While the liver is the primary organ of metastasis from pancreatic and colon cancers, the relatively rare incidence of prostate cancer metastasis to the liver has the worst outcome. The liver -- whose primary function is to filter the blood coming from the digestive tract, detoxify chemicals, metabolize drugs and excrete bile -- plays a role in other cancers, as well.
``There is already evidence that having fat in the liver promotes primary cancer there,'' said study co-lead investigator Dr. Shelly Lu, director of the Division of Digestive and Liver Diseases.
She and the other investigators, working on four separate projects, will study how signaling, or ``crosstalk,'' between the liver and cancer in a distant organ alters the liver environment to allow cancer to spread and thrive there.
The liver in the context of a high-fat diet may, for example, send a signal to cancer cells in the prostate gland that in effect says, ``This is a great place to live,'' Bhowmick said.
Cancer cells also ``talk'' to the liver, seeking to move there for the better blood circulation or nutrients that the liver, and specifically fatty liver cells, may provide. Every person's liver has some fat, but if more than 5% of hepatocytes -- the main cell type in the liver -- contain fat, that condition is called nonalcoholic fatty liver disease.
``We're looking at the crosstalk in three cancer types,'' said Bhowmick, referring to cancers of the pancreas, colon and prostate. ``If we can help block those signals, perhaps we can prevent the cancer from ever getting to the liver and reduce mortality from the disease.''
The five-year study funded by the grant is timely. Obesity poses a major health threat -- more than 71% of U.S. adults ages 20 and older are overweight or obese, according to the federal Centers for Disease Control and Prevention. About 90% of obese people have a fatty liver.