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What Can Go Wrong: The Causes of Cancer

Despite how common cancer is, doctors and researchers do not truly understand how or why most cancers start growing. Even though they have many ideas and insights into why a cancer cellSEL — One of the most basic components of all living things that together form the entire body and contains many smaller parts that guide its function grows and progresses into a tumorTOO-MER — An abnormal growth in the body, they are not completely sure what causes the first cancer cell to form. But we're going to talk about three well-known theories for how malignantMA-LIG-NENT — A cancer or abnormal tumor that grows uncontrollably and may spread to other parts of the body tumors grow.

Time to grab your keys and go for a drive. A cell in your body will be our car.

Yes, we're asking you to really use your imagination for this one! And, please keep in mind, the following comparisons are completely made up.


A car has many parts that work together to ensure it runs efficiently, just like a cell. Many individual components must work in harmony for the cell to function properly. An important part of any car is the engine. The engine makes the car move faster or slower, but the gas pedal is what controls speed.

Similarly, an important part of any cell is the DNADEE-OX-SEE-RYE-BOW-NEW-CLAY-IK AH-SID — The blueprint of a cell that controls the function of all components within the cell. DNA is the blueprint of the cell that contains all of the information needed to control the cell. The DNA influences what the cell does and how it behaves, just like the gas pedal.

Sometimes the gas pedal of a car malfunctions, and the driver loses control of the car’s speed.

DNA MutationD-N-A MU-TAY-SHUN — A change in DNA that can lead to or cause cancer

A mutation in your DNA can affect the function of the cell, causing the cell to grow wildly. A mutation is defined as an error in the basic make-up or blueprint of the cell. If this error occurs, the cell malfunctions. The mutation causes the cell to divide and replicate uncontrollably (and very quickly), resulting in cancer.

This is like the driver pressing their foot on the gas pedal but not being able to release the pedal. When this happens, the car accelerates too quickly, and the driver loses control.


So, what can cause a DNA mutation? There are many reasons, but one of the most common is carcinogensCAR-SIN-O-GIN — Chemicals known to harm normal DNA when exposed. Carcinogens are chemicals known to harm normal DNA when exposed. An example is cigarette smoke. Cigarette smoke can act like rust on a pedal, making it stick.

The loss of normal apoptosisA-POP-TOE-SIS — The programmed death of a cell; when a normal cell is expected to die is another explanation for how some cancers grow.

Apoptosis is one of those complicated-sounding medical words, but the definition is simple. Within your body, certain normal cells are expected to grow and die every day. These cells have a predetermined, planned death. The planned or expected cell death is called apoptosis.

Imagine that someone is driving down a road, and all of a sudden, the brakes fail. Somehow the car’s computer was hacked and infected by a virusVAI-RUS — A foreign invader in the body that causes cells to function differently and can be spread to others through direct and indirect paths, causing the driver to lose control of the brakes. As the car approaches a busy intersection, the driver notices the other cars aren’t slowing down either. The virus has affected all of the other cars near the intersection, too.

Speeding towards the red light, the driver tries to apply the brakes again, but still nothing happens. Suddenly, they hit another car. Before long, cars are piling up from all four directions. Sounds like something out of a movie, right?!


This pile-up is a lot like the growth of an abnormal massAB-NOR-MOL TISH-YOU — The accumulation of cells that aren't supposed to be there in the body.Losing control of the car’s brakes is like the loss of normal apoptosis. Some cancer cells keep functioning and don’t die as expected, and these cells accumulate into a large cell pile-up, or tumor.

watercolor car

GenesJEAN — A part of DNA that determines human characteristics might play the biggest role in the growth of cancer cells.

As the cancer community learns more and more about cancer, one factor seems to always rise to the top—genes and gene mutationsJEAN MU-TAY-SHUN — A change in DNA that can lead to or cause cancer commonly cause cancer growth. Sometimes these mutations are caused by external risks, like the carcinogens we discussed earlier. Other times, these mutations are passed down from parent to child, just like the color of our eyes is passed in genes.

The improved understanding of the role of gene mutations in cancers has brought about a new area of research in cancer care called personalized medicineThe examination of cancer cell genes (and other markers) to help predict patient outcomes, response to treatment, and the underlining causes of cancer using very advanced science techniquesor precision medicine.

Personalized medicine is the examination of cancer cell genes (and other markers) to help predict patient outcomes, response to treatmentREE-SPONSE — The change in size of a cancer after treatment, and the underlining causes of cancer using very advanced science techniques (and a lot of data). Personalized medicine has brought to light many new gene-related factors that cause cancers to grow, like mutations that lead to overactive proteinsPRO-TEEN — A naturally occurring, large, complex substance made up of amino acids that is an essential part of living organisms or cells that don’t regulate growth correctly.

And, knowing what causes cancers to grow, makes it a lot easier to develop very specific treatments to stop the cancer.

Although a fairly new practice, personalized medicine has the ability to greatly improve the lives of patients with better treatment recommendations and outcomes. However, despite massive amounts of research, no one truly understands why some people get cancer and others don’t. Sometimes cancer just happens.

There are situations that can increase a person’s chance of developing certain cancers. Each type of cancer has a unique set of factors that put you at a higher risk (chemical exposures, like smoking, and a family history of the disease are two of the most common risk factors).

But cancer forms, despite our unhealthy and healthy choices. It happens by chance, like finding a dandelion in your garden.
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