Reviews | Can a neuroscientist fight cancer with mere thought?
For example, we know there are circuits in the brain that control and monitor breathing, and we know that these circuits connect to other regions of the brain that imbue pain with its negative emotional tone. So, even if we don’t understand all the details, we can design experiments to test the hypothesis that work of breathing can dampen pain perception by transmitting electrical signals from respiratory centers to emotional pain centers in the brain. to reduce their activity. .
But is the perception of pain a good general example of the usefulness of body/mind medicine? After all, the perception of pain happens in the brain, so it’s not too hard to imagine that it could be affected by the way we behave or think.
What about a life-threatening disease that often manifests outside the brain? Could the course of cancer progression be affected by behavioral practices like meditation or breathwork? The short answer is that we don’t know, but the longer and more interesting answer is that, in at least some cases, there are reasonable and testable hypotheses about how this might happen.
A potential biological explanation is that some type of signal must be sent from the brain to cancer cells in the body. The primary means by which the brain communicates with the body is through nerve fibers which form pathways from the brain to the body to conduct electrical signals, which in turn release neurotransmitter molecules at their terminals. (The brain can also communicate with the body through molecules secreted into the bloodstream.)
In recent years, we have learned that certain types of cancer in the body receive nerve fibers, which originate in the brain and are transmitted to the body via electrochemical signals that travel in a chain from neuron to neuron. These include tumors of the lung, prostate, skin, breast and pancreas, and gastrointestinal system. This innervation of tumors often contributes to the growth and spread of cancer. In most cases, if you have cancer and your tumor is innervated, then your prognosis is worse. However, there are many types of nerve fibers and there are some that can slow the progression of cancer and still others that have no effect.
Understanding the cellular and molecular mechanisms by which innervation contributes to tumor growth and spread is an active and promising area of investigation. A recent report from the lab of Sébastien Talbot at Queen’s University in Kingston, Ontario, showed that melanoma is often innervated by nerve fibers that secrete a chemical messenger. This compound, CGRP, acts on a particular type of immune cell, inhibiting its ability to fight tumors.
When these nerve fibers were silenced in mice with melanoma, which stopped the secretion of CGRP, the spread and growth of melanoma was significantly reduced, which tripled the survival rate of the mice. This means that blocking the electrical activity of these nerve fibers allowed immune cells to help keep the cancer under control.