Cancer is a difficult and challenging disease to treat. When detected early, some cancers can be pushed into lengthy and sometimes permanent, remissions. With more aggressive cancers, however, these sorts of remissions are much more difficult to achieve.
What amazing news, then, that a team of scientists have recently figured out how to alter a virus genetically to create a potential cancer-fighting vaccine. This vaccine, the scientists say, appears to have the ability to attack a variety of advanced cancers.
The theory behind the cancer vaccine is that people with cancer tend to have defects in their immune system. This defective immune system compromises their ability to respond to tumors. The vaccine has to make up for this by activating immune cells that are capable of killing tumors. These newly activated immune cells also have to survive long enough to get to a tumor and destroy it.
For the study, 28 patients with advanced, recurrent forms of lung, colon, breast, appendix or pancreatic cancer were recruited. All the participants had already failed several rounds of standard chemotherapy. The researchers then administered a specially prepared vaccine multiple times over a period of three months. According to the researchers, five patients displayed a response to the therapy. Two patients who had already been in remission stayed in remission. Two patients saw their cancers stabilize, and a liver lesion in one patient with pancreatic cancer was no longer evident.
The research team noted that the responses tended to occur in patients with smaller tumors and in those receiving higher doses of the vaccine. The vaccine also managed to evade the immune systems T cells, which could have shut down the body’s immune response, the researchers said. And this happened even though T cell levels were elevated in some patients; it seems the vaccine was able to get around them.
The researchers caution that this is the first study in cancer patients with this type of vaccine, with a relatively small number of patients treated so far. So, while the immune response data are promising, further study in a larger number of patients will be needed to assess the clinical benefit of the vaccine.
One vaccine to treat prostate cancer was recently approved by the U.S. Food and Drug Administration. However, many other cancer vaccines have shown early promise and have not panned out, so caution is still needed when considering the potential of these vaccines to eliminate cancer.