How Your Body Fights Cancer

Our immune system is amazing.  It easily recognizes foreign entities like viruses, and unhealthy bacteria, and then proceeds to get rid of them through various immune system responses.  So, why won't our immune system attack cancer cells?  Well, the answer to that is complicated. 

Immune System Defense

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There are 2 very simple responses to the question of why our immune system doesn't fight cancer.  The first being, that actually, our immune system does try to protect against malignant cells, but the challenge is in part two - cancer cells are our own cells from our body, and our immune system is hesitant to fight itself - our own cells.  Think about when the immune system begins to attack healthy cells in your body - this is what happens in autoimmune diseases, so this is something we want to avoid.

With all of that confusion, our immune system has to learn to recognize malignant cancer cells, without triggering an autoimmune response.  In fact, without any help, it's already doing a pretty good job of this.  There's a gene called the 'Proofreader Gene' (P53) that is in every cell in our body except red blood cells.  This gene can identify cells that are abnormal or have become malignant.  When it finds an abnormality, it will send NK cells (Natural Killer cells, a type of lymphocyte or white blood cell) to attack the cancerous cell.

Cancer cells, in simple terms, are not foreign entities, but cells from our body that have mutated to the point where they multiply without dying off.  They grow without any self-regulation to stop and die the way a normal cell in your body behaves.  To address this, our immune system needs to 1) identify the mutation, 2) cause the cancer cell to die (apoptosis).

The Immune System: Stages of Fighting Cancer

The immune system has several lines of defense against cancer, which is why we don't get cancer all the time.  The body's cells are constantly mutating, and most of these mutations are processed and disposed of by the immune system.  So, how does our immune system protect against cancer?

Protect Healthy Cells

Our immune system uses antioxidants to protect healthy cells from damage caused by carcinogens that we are exposed to.  A key part of cancer prevention, and survival after cancer treatment, is to avoid carcinogens and toxins, but also make sure you get plenty of antioxidants in your diet, and water to flush out toxins.  Keeping a clean healthy environment inside your body, supports your immune system in protecting healthy cells.

Repair Damaged Cells

DNA in cells are damaged from 50,000 to 100,000 times a day.  It's pretty remarkable that our immune system is constantly dealing with this while we go about our normal healthy existence.  The immune system identifies this damaged DNA and send repair proteins.  It's at this point that the DNA is either repaired, or the irreparable cell is killed off, or in some cases, the cell can become cancerous.  Given the large numbers of damaged DNA every day, cells that become cancerous are actually quite rare.  The issue is stopping it when it happens.

Encouraging Cancer Cell Death (apoptosis)

The next stage of the immune system fight against cancer, is to identify the cancer cells, attacking the cell, or encouraging cancer cell death.  The main characteristic of a cancer cell is it has reprogrammed itself NOT to die.  It just multiplies and multiplies unchecked.  This is the part of the immune system that is tricky.  If caught early, the immune system works to kill off the cell.  Cancer becomes an issue when it moves beyond this initial stage, and is allowed to multiply rather than execute its programmed cell-death.

Both natural approaches to immunotherapy as well as personalized medical immunotherapy treatments all work at this level to support the immune system as it tries to induce mutated cancer-cell death.

The Challenge

Unfortunately, some cancers cells adapt. By creating cytokines, which allow the tumor to communicate with and confuse the immune cells, the cancer can control the process that the body uses to regulate the immune response.  When the immune system hits a 'checkpoint', which determines whether the immune response is still needed, the cancer cell can tell the immune system to stop.  So, even when the immune system recognizes a cancer cell, it may not finish the job, leaving the cancer cells free to grow.

The longer the cancer cells interact with a weakened immune response, the more they can adapt, which makes it easier for them to further weaken and manipulate the immune cells.  


The latest discoveries in immunotherapy try to address these issues.  Immunotherapy tries to overcome the points at which the cancer shuts down the immune response, or enhances the body's early attacks before the cancer takes hold. 

Interestingly, every immune system is different, as it has learned to adapt and grow through our life experience of fighting disease, as well as genetics.  So, every body responds differently; an immunotherapy approach that works for one person may not work for someone else.  Immunotherapy as a Cancer Treatment is becoming a highly personalized approach to treating cancer.

New developments are happening every day.  You may want to ask your doctor about available immunotherapy options.