Cancer and stress, part 1
This can be a very difficult topic to discuss. What does stress have to do with cancer? We already know that chronic stress can suppress the immune system. Immune cells move around and patrol the body to ensure that any bacteria or fungi in the body is killed to avoid infection. That’s the front line of defense in the immune system. The background army of these immune cells are in charge of checking the tissues throughout our body to ensure they are healthy. If any cell is unhealthy, immune cells eliminates them. This avoids potential problems by removing cells that can cause toxicity and damage other cells.
So what does stress have to do with cancer? In order to approach this subject, we need to explain a few things, so we can understand how stress impacts us.
What exactly is cancer? Cancer is a problem of uncontrolled growth. Cells start growing much faster than they should, creating tumors and growing inappropriately. Our bodies have a perfectly controlled, proper growth cycle. The only time continuous growth takes place is when we are developing. When this happens, there are many genes that control this continuous growth from the point of embryo and into our younger years. Once growth caps off, the gene that promotes continuous growth switches off, and normally stays off for the rest of our lives.
Cancer is when there is a re-activation of our growth genes. These genes – oncogenes – have no business being re-activated, but something triggers them. This reactivation promotes uncontrolled growth, and it can happen in any part of the body. What are the causes? There can be a few different sources. One of them is radiation. Another is carcinogens or chemical components, like being exposed to too much chlorine. Additionally eating certain foods that have lost oxygenating properties can also be a factor. There are also viruses that can cause this – this is rare, but possible. Regardless of the reason, something causes the growth genes to switch on.
Cancer develops when there is a multitude of mutations in the cells. An uncontrolled growth begins once there is a cancerous cell. For the cancer to grow successfully, this cancer cell transitions to another stage. Tumors start growing. These tumor cells become hungry. They need to eat and they grow rapidly because they have a high metabolic rate.
The challenge for these cells is not so much activating themselves to divide, but in getting food to eat. One of the things you’ll see with cancer, as it progresses, is these cancer cells giving signals that tell the capillaries blood vessels to supply more nutrients to the tumors. This is called angiogenesis. These cancer cells are very efficient at getting nutrition by sending signals to the nearest capillaries so these blood vessels grow to reach the tumors .
In the early phase, our defense against cancer is the immune cells in the body. Natural killer cells detect these mutant cancer cells. They normally have enough weapons to go to these cancer cells and destroy them. These tumors can be spotted early on and destroyed. This is our first line of defense. Also, other factors, like tumor necrosis, help to destroy cancer cells.
The cancer transitions to a more mature state by getting enough nutrition to keep growing. If we are in a generally healthy state, our cells will start forming a fence around themselves to protect against any cancerous ones. This process puts an end to the growth by calcifying these small tumors.
Now let’s talk about what stress does to the immune system. Chronic stress starts to impair the body’s defense in the immune system. But how does this happen?
Let’s review what happens when we are under stress. We have a few anatomic parts of the brain that participate as an axis to the stress mechanism. In the brain we have the hypothalamus and pituitary gland. In the body we have the adrenals. Remember that the brain makes neural and projections connections to try and protect you against real danger. Information arrives through your eyes and other senses. Your limbic area, where thoughts are created, will receive the information about the danger and promotes action in less than a thousandth of a second. The hypothalamus will send a signal through the pituitary gland and certain neurotransmitters travel through neurons, sending a message to the adrenals (located above your kidneys). These are small glands that receive messages of danger, and produce hormones that are released into the bloodstream. These hormones shut down the production of insulin, releasing sugar and fats into the bloodstream. At the same time, other parts of the central nervous system are turned off, and the sympathetic nervous system is activated in greater proportion.
Let’s go back to the brain. The information registered as danger becomes the focus during any stressful time. Your brain focuses it’s attention on this, and this alone. So much that any other connections of the brain are dismissed for the time being. In moments like these, nothing else is important. This includes repairs, digestion or immune defenses. Everything else is seen as less important. The body will deal with those problems later, but the body needs all the energy available to keep you alive. This stress mechanism causes energy to be delivered to your lungs, heart, muscles and brain so you can stay focused on escaping danger – running or fighting for your life.
The neocortex, located in the brain, receives information of danger right after the limbic area does. It analyzes the data and send signals with a course of action to follow to ensure that we make smart choices. If the neocortex realizes there’s no real danger, it send signals to the limbic area to correct the message and turn off the stress mechanism. The hypothalamus will initiate a reverse action, and everything goes back to normal. Real danger causes the neocortex to proceed in helping you survive. This is what the stress mechanism is for.
The stress response will also be present when we experience new episodes. The neocortex area will always analyze the data and send signals to the limbic area to suggest how best to handle each stressful event. This mechanism also participates in the regulation of different organs in the body. When there is stress, the production of chemicals from the adrenals increases in our bodies. These chemicals are cortisol, epinephrine and norepinephrine. In the brain, a series of neurotransmitters participates in this process.
This is a highly simplified picture of how the mechanism of stress works. After the danger is over, everything goes back to normal. Depending on the problem at hand this can last a few seconds to a few hours. As we’ve learned, the stress mechanism has deep implications for our health. In our next blog we’ll continue to look at this fascinating part of the body’s system.