Getting Down to Basics - Where does cancer come from?

Heads up, folks - this is an in-depth, science-y read. Take your time and enjoy!

You may know cancer as a terrifying, life-threatening disease that turns people's lives upside down. Maybe you’ve had a first-hand experience with cancer, either watching your loved ones battle with the disease, or perhaps you’ve fought it (or are still fighting it) yourself. Although individuals with a healthy lifestyle are typically less likely to develop cancer, young, old, fit or unfit, cancer does not always discriminate.

So, maybe you've asked yourself, "how the heck does cancer develop?". Although the answer to that is still not fully understood, there is a basic series of events in cancer development.

There are 3 steps that are used in the study of cancer to help explain how your original healthy cells can become abnormal cancer cells: 1) initiation, 2) promotion, and 3) progression. These steps comprise the process of “carcinogenesis” – the changing of a normal cell into a cancer cell.

Step 1 - Initiation

During the first step in carcinogenesis, a carcinogen (any substance that can lead to cancer, for example, some chemicals in cigarettes) binds to a gene (or genes) in your cell(s). This can happen in any part of your body. Genes are like the brain of the cell and make messages to tell your body's cells about tasks it needs to perform, such as digestion, breathing, and other body processes.

The binding of a carcinogen to a gene can disrupt normal cell tasks by causing a mutation of the gene - it changes it by turning the cell towards the “side of evil”. In cancer initiation, the carcinogen binds to genes that are responsible for the dividing of the cell. A mutation in this gene causes the cell to divide very frequently and without consideration as to how many cells the body truly needs to be healthy. Other genes that may be affected include those that tell the cell when it needs to repair itself, and those that tell the cell when it should destroy itself.

Typically, the mutations are caused by an "epigenetic event" and are REVERSIBLE. This is because it doesn't affect the cell's DNA - which means the change is not permanently imprinted in the cell.

Epigenetic events are begun by "promoters", which include reactive oxygen species (ROS; types of chemicals that contain oxygen and can damage DNA), endocrine disruptors (substances that interfere with the body's hormone system), oxidized fats (fats that have changed and taken a form that is harmful to the body), and polycyclic aromatic compounds (found as byproducts of fuel burning - gas, oil, coal, etc).

An epigenetic event occurs when a cell is exposed to these promoters and changes the genes in the cell, but not the DNA. There is still a chance for an intervention to a) cause the cell to die or b) repair the messages from the genes by reversing the epigenetic changes.

In essence, step 1 is REVERSIBLE.

Step 2 - Promotion

Step 2, promotion, involves three processes that occur at the same time: a) the same gene affected in step 1 is repeatedly beaten and mutated by the same carcinogen(s) or a different carcinogen(s), b) other types of genes besides the ones in step 1 are repeatedly beaten and mutated by a single or multiple carcinogen(s), and c) continuous cell division of the originally mutated cell(s).

Once a carcinogen has caused a mutation within a cell, a cell generally has to undergo many cell divisions before the mutation "sticks" and becomes an imprinted part of the cell's DNA. DNA is the building blocks of a gene. Once the cell's DNA has changed, the mutation in the gene is permanent.

In some cases where cancer doesn't develop, this mutated cell is repaired or destroyed before the mutation sticks. In cancer, the mutated cell escapes the defences of the body and becomes a permanent change in the cell's DNA.

Like Step 1, Step 2 is REVERSIBLE, but unfortunately these cells will never fully recover to their original normal cell function before entering step 1; therefore, the changes in their DNA will remain. The good news is, they can remain this way for life without becoming cancer, or they might eventually be destroyed and safely disposed of by the body's natural defences and repair mechanisms.

Step 3 - Progression

If the mutations aren't reversed, or if the body is still unable to get rid of the mutated cells, the mutated cells will continue to step 3 - progression. In step 3, additional mutations in genes continue to occur. The cells also pick up a few new tricks to help themselves survive and prosper.

Blood carries lots of nutrients, which can be used to feed the mutated cells’ growth and cell divisions; therefore, these cells begin building their own blood supply to improve and keep up demand. The mutated cells also send out signals to attract immune cells to start a fight. This causes inflammation. Inflammation feeds the mutated cells’ desires to prosper by creating ROS, making further gene damage, and producing substances that eat through nearby tissues, helping the mutated cells to invade the surrounding area. Meanwhile, the immune cells just thought that they were helping by getting rid of an invader!

Once mutated cells enter step 3, it is considered cancer and the process is IRREVERSIBLE. The only known way to heal in step 3 is through anti-cancer agents, such as chemotherapy, radiation, and surgery.

At this point, the mutated cells have free-range and continue to divide and conquer, and make more mutated cell offspring in their images. These mutated cell offspring will go on to form a mass of cells like itself (a tumour), interfere with normal body functions (beginning the signs and symptoms of cancer), and/or spread into the surrounding organs and tissues (invasion) or move off to other parts of the body to set up camp elsewhere (metastases). This is the step at which cancer is usually detected through observation of signs and symptoms that the affected individual experiences, or through imaging, labs, or physical exams by a doctor.

How Can We Stop Cancer Before It Begins?

So, where can we intervene along these steps to stop cancer in its tracks? Here are 3 BIG options:

1) Limit your exposure to carcinogens and decrease your chances of cancer initiation all together. We will discuss different types of carcinogens and where they are found and how they can be avoided in upcoming blog posts. Cancer is still PREVENTABLE if the cancer-causing substance is removed early.

2) There are many ways to help strengthen your body so it can fight off and kill mutated cells. This is often accomplished by strengthening your immune system. In addition to fighting colds and flus, the immune system is also responsible for recognizing and getting rid of mutated cells.

3) Increase cancer-fighting substances through diet. Try loading half of your plate with vegetables at every meal, include a greens powder in your smoothies, and have fruit instead of baked goods for dessert.

Overall, although cancer can be unpredictable, there is something you can do to improve your odds of living cancer-free. Keep reading my blog posts to learn more about how to fight cancer and to optimize your health to be the ultimate form of who you are meant to be.

Definitions:

Apoptosis – “programmed cell death” or “cell suicide”. When a cell is abnormal, it has the ability to cause itself to die. This is something normal that our bodies are programmed to do when cells become old or dangerous (like in cancer).

Carcinogen – a substance that can attack a cell and make it cancerous.

Carcinogenesis – the process that healthy cells undergo if they’re changing into cancer cells. It involves 3 steps: 1) Initiation, 2) Promotion, and 3) Progression.

Epigenetic change – changes in our cells that can change the way that genes are interpreted without actually acting on or changing the genes. This one is confusing to explain, even to most scientists! But it’s important to understand that an epigenetic change is reversible.

Invasion – penetration of cells into local organs and tissues.

Metastases – the spread of cancerous cells from its original location to another location in the body.

Mutation – a change within a cell’s genetic material that is different from its normal genetic material

Promoters – a substance that causes an epigenetic change. This includes ROS, endocrine disruptors, oxidized fats, and polycyclic aromatic compounds.

Tumour – an abnormal mass of cells. Can be benign (not cancerous) or malignant (cancerous).