Breakthrough: Vaccine Against Cancer!
by Shlomo Maital
Cancer immunology [use of the body’s own immune system to kill cancer cells] has been chosen as the “Breakthrough of the Year” by the editors of Science. A fascinating report was published in the December 20 issue. (This blog is longer than usual, because the topic is so important).
For example: According to the U.S. National Institutes of Health: The photo shows an aspirin-sized disk, the first therapeutic cancer vaccine implanted beneath the skin. “We know it can eradicate melanoma in mice—the deadliest form of skin cancer—with impressive efficacy . Now, it’s being tested in human trials.”
One day, hopefully, chemotherapy may be replaced by immunotherapy. Instead of poisoning cancer (and our own body), we may be able to trick cancer cells, which are good at defeating the body’s own T-cell immune system, and enable our T-cells to kill cancer cells before they become tumors or even after.
What is the science here? According to the NIH, vaccines prevent illnesses, like smallpox, by introducing dead or weakened germs, to teach the body to create antibodies if it does appear. We already have vaccination against the human papilloma virus (HPV)—a powerful way to prevent cervical cancer. The new anti-cancer vaccines work differently. They’re given to patients who have already been diagnosed with cancer. Once given they “behave like traditional vaccines—by teaching the immune system how to seek out and destroy a target—in this case, a tumor. “
“ A couple of cancer vaccines have already been approved by the FDA. However, producing these vaccines is typically a cumbersome, time-consuming, and expensive process. First, immune cells are taken from a patient. The cells are modified and reprogramed in the lab, and then they are injected back into the patient. In the vaccines approved to date, this elaborate production line has extended patient life—but only slightly. And so, some researchers began to look for a simpler, and perhaps more effective, way to make therapeutic cancer vaccines. About four years ago, an NIH-funded, multidisciplinary team based in Boston and Cambridge came up with an approach that would modify and reprogram patients’ immune cells—inside the body, not in a lab!! The team first developed a porous polymer implant, made from the same material as biodegradable sutures and meshes. Then they infused the disk with a collection of three immune stimulants that recruit the immune cells, activate them, and imprint them with a chemical signature of the tumor that is targeted for destruction.
“The first of the three immune stimulants is a drug called leukine (also known as GM-CSF), which summons millions of dendritic cells, key immune cells, to enter the implant. The second is DNA that mimics viral and bacterial DNA and sends a danger signal that activates these cells. The third ingredient is the personalized part of the recipe: a combination of proteins made from the patients’ own tumor. It gives the dendritic cells the unique signature of that person’s tumor, which they share with the warrior T-cells. The “educated” T-cells are then primed to hunt and obliterate the tumor.”
The new approach is metaphorically like training cancer-killer cells to a) spot cancer, and b) kill it, by first teaching them to recognize the enemy and then, giving them ‘martial arts’ skills to destroy it.
Some of the most advanced work in the world on cancer immunology is done in my country, Israel. Prof. Leah Eisenbach, at the Weizmann Institute, Rehovot, has done breakthrough work. A company known as Compugen has developed antigens proven useful against cancer, and sold two of them for hundreds of millions of dollars to Bayer.
We know today that there are more than 120 different types of cancer. Each requires its own variant of chemotherapy. While survival rates have risen enormously, there has to be a better way than ‘tailored poison’. There is. Immunotherapy may point the way. If you know someone who has cancer, or whose loved ones have it, draw their attention to this new breakthrough. There is definitely hope, and the progress may be relatively rapid.