Researchers are testing a protein therapy that stops breast and ovarian cancer from metastasizing in mice .
“ The majority of patients who succumb to cancer fall prey to metastatic forms of the disease , ” says Jennifer Cochran, an associate professor of bioengineering at Stanford University .
Today doctors try to use chemotherapy to slow or stop cancer from spreading from the original tumor site to other parts of the body , but these treatments are unfortunately not very effective and have severe side effects .
The new therapy doesn’t have side effects. It works by preventing two proteins–Axl and Gas6–from interacting to initiate the spread of cancer .
Axl proteins stand like bristles on the surface of cancer cells , poised to receive biochemical signals from Gas6 proteins .
When two Gas6 proteins link with two Axls, the signals that are generated enable cancer cells to leave the original tumor site , migrate to other parts of the body , and form new cancer nodules .
To stop this process Cochran used protein engineering to create a harmless version of Axl that acts like a decoy . This decoy Axl latches on to Gas6 proteins in the bloodstream and prevents them from linking with and activating the Axls present on cancer cells .
In collaboration with Amato Giaccia , professor of radiation oncology , the researchers gave intravenous treatments of this bioengineered decoy protein to mice with aggressive breast and ovarian cancers .
Mice in the breast cancer treatment group had 78 percent fewer metastatic nodules than untreated mice . Mice with ovarian cancer had a 90 percent reduction in metastatic nodules when treated with the engineered decoy protein .
A paper published in the journal Nature Chemical Biology details the results .
“This is a very promising therapy that appears to be effective and nontoxic in preclinical experiments ,” Giaccia says .“ It could open up a new approach to cancer treatment .”
Giaccia and Cochran are scientific advisors to Ruga Corp. , a biotech startup in Palo Alto that has licensed this technology from Stanford . Further preclinical and animal tests must be done before determining whether this therapy is safe and effective in humans .
《An engineered Axl 'decoy receptor' effectively silences the Gas6-Axl signaling axis》，Published on Journal《Nature chemical biology》21 September , 2014 .