Cancer Research UK scientists are making headway in the fight against cancer. Until recently, immunotherapy has been considered a pretty rough method of battling what has been called the "Emperor of All Maladies" by Siddartha Mukherjee. Chemotherapy and immunotherapy have been the main treatments for patients suffering from the disease. Immunotherapy often comes with harsh side effects and is described by researchers as being "Powerful-but-blunt weapons" that do more harm than good.
But imagine if doctors could tailor treatments based on the patient's own body? That's what the minds at Cancer Research UK are working on, and they have achieved a major breakthrough. Their study is published in the journal, Science.
Immunotherapy is essentially an attempt to enlist the body's immune system in order to defeat diseases such as cancer. The difficult thing about fighting cancer is getting the treatment to attack the disease while leaving healthy cells alone. This is why chemo often does more harm than good. What needs to be done to make treatments more effective is to somehow guide the immune system to certain regions of the mutated cells. Cancer growth has a way of getting ahead of our body's defenses, and this can cause the disease to spread and branch out similar to the way a tree grows.
Researchers from the study relate current methods of killing cancer to trying to kill a tree by cutting off its branches. It simply grows more. Immunotherapy has the potential to chop down the entire tree.To stop this advance in growth, antigens are needed to flag the diseased cells. Only then will immune cells spot the cancer and attack the proper region of the growth. Antigens change in cells that are damaged or ill, and it's the job of T-cells to identify any changes in the signals of antigens. But cancer cells are able to block signals emitted by the antigens, and T-cells then have no way of recognizing the cancer.
"One of the reasons why some cancers – lung cancer and melanoma in particular – are so hard to treat is because they evolve so rapidly they quickly outpace the drugs we use to stop them," says Professor Charlie Swanton, the world's leading expert on tumor growth.
Dr. Nicholas McGranahan worked on Swanton's team and told Cancer Research UK's blog about his work with computers mapping the advancement of tumor development.
"We have been using this type of analysis to predict what sorts of mutations are present across the tumor, so we wondered whether we could also use it to look for antigens shared on all tumor cells... We had suspected that the diversity of mutations we see in tumor evolution would be reflected by the antigens present on the cancer cells – but until now we had no proof."What the study concluded was that since tumor cells are capable of emitting signals that block T-cells, what is needed is an immunotherapy drug that blocks what experts call "stop signals." After running a drug known as pembrolizumab (Keytruda) through their prediction program and testing it on 13 patients, the researchers learned that 12 responded well to the treatment.
A key point of this treatment would be to deliver drugs to key points of vulnerability of the tumor. This would require personalized treatment for every patient, some who unfortunately may not have the time required to tailor their treatment. But despite that finite nature of time, Swanton is enthusiastic that his team in on the road to something big.
"It's incredibly exciting," he says, "and although it's early days, it offers hope that we might just be able to turn the tide against advanced cancer – something we desperately want for our patients."
A better understanding of T-cells, and how they interact with cancer cells, isn't only helping destroy tumor cells, it's also helping with blood cancer. One recent leukemia study has proven that altered T-cells have eliminated the disease in 94 percent of patients. Hopefully, with further advancements in science and immunotherapy, the threat of cancer can become a thing of the past.[Photo via Flickr/CC]