Vaccine Stops Tumor Spread in Mice
SUNDAY April 18, 2010 -- A new study in mice suggests that a transcription factor normally found in male germ cells could become a target for cancer vaccines.
A transcription factor is a protein that controls the transfer (or transcription) of genetic material from the DNA to messenger RNA. This particular factor, known as Brother of the Regulator of Imprinted Sites (BORIS), promotes tumor growth.
Scientists were able to develop a vaccine from BORIS that was effective in helping stop the spread of a breast cancer-like tumor to other parts of the body, a process known as metastasis.
The vaccine "is capable of inducing strong and effective antitumor immunity, but the efficacy of this [strategy] could be even better if one could eliminate immune suppressor cells," lead researcher Michael G. Agadjanyan, head of the department of immunology and professor at the University of California, Irvine's Institute for Molecular Medicine, said in a press release.
Researchers tested the value of a mutated virus using the factor on mice with a form of cancer similar to breast cancer found in humans. They delivered the vaccine into the body by using immune cells known as dendritic cells, whose treelike branches form connections with other cells in the body.
The factor delivered by dendritic cells "elicited strong antitumor cellular immune responses in tumor-free mice," Agadjanyan said. "More importantly, therapeutic vaccination dramatically inhibited both tumor growth and the number of metastases in the lungs of tumor-bearing mice."
He cautioned, however, that the BORIS-based vaccine did not entirely eliminate tumors or stop the spread of cancer. For that reason, it should be combined with other strategies that enlist the immune system to combat cancer, he said.
The study findings were scheduled to be released Sunday at the annual meeting of the American Association for Cancer Research in Washington D.C.
Posted: April 2010