Gene target expands treatment prospects for liver cancer
The limited therapeutic options for hepatocellular carcinoma (HCC)—which has one of the worst 1-year survival rates of any cancer type—may have just broadened with the discovery of a new molecular target for the disease.
A research group headed by Scott Powers, PhD, director of the Human Cancer Genome Center at Cold Spring Harbor Laboratory (CSHL) in Cold Spring Harbor, N.Y., has learned that liver tumors are driven not just by the already known CCND1 gene, but also by a neighboring gene: FGF19. CSHL mouse experiments revealed that up to 15% of liver tumors are triggered by the hyperactivity of this gene, and that using an antibody to make the gene inactive inhibited the growth of liver tumors.
“This is an important advance considering that there are currently no genetically targeted therapies for liver cancer,” Dr. Powers affirmed in a statement describing his group's findings, which were published in the journal Cancer Cell (2011;19:347-358).
The researchers found that when FGF19 exists in multiple copies—well in excess of the normal two per cell—it triggers liver cancer.
“It turns out that liver tumor cells with this FGF19 amplification are strongly dependent upon the gene's continued expression to sustain tumor growth,” explained Dr. Powers.
When cancer cells become oncogene-dependent—that is, when they start to rely exceedingly on a single oncogene—treatments can be devised to combat these molecular targets. This approach has been successful, for example, in creating therapies for breast cancers that carry multiple copies of the HER2 gene.