The Science of Cancer 101
A six-minute overview of the science behind one of the deadliest diseases facing mankind.
Accounting for nearly 10 million annual deaths, cancer is recognized as a leading cause of mortality worldwide. The good news, however, is that we have come a long way in the fight against cancer. New drugs are being developed, and new technologies designed to detect cancer at earlier stages are being introduced.
But what is cancer?
And what is it about this disease that makes it so deadly?
Understanding cancer
Defined by the National Cancer Institute . . .
Cancer is a disease in which some of the body’s cells grow uncontrollably and spread to other parts of the body.
Cancer is a genetic disease.
What does this mean?
Well, it means that cancer is caused by changes in genes, particular changes that affect cellular functions. These changes can occur because of errors when cells divide, because of damage to DNA as a result of different toxins or because they were inherited from parents.
Generally, our cells grow and divide to support our body’s functions. They do this through a process called cell division. As cells near the end of their lifespan or become damaged, they are replaced by new cells. However, cancer starts with genetic changes that interfere with this systematic process. For example, abnormal cells continue to grow and eventually become uncontrollable. These cells may come together to form a tumour.
Tumours are abnormal lumps of tissues that may be benign, meaning non-cancerous, or malignant, meaning cancerous.
- Benign tumours: These tumours tend to grow at a slow pace and do not spread. When removed, they usually don’t grow back.
- Malignant tumours: Malignant tumours can grow rapidly, invade and destroy nearby normal tissues, and spread throughout the body. They are also more likely to grow back after removal.
However, it is important to note that not all cancers form tumours, including leukemia, most types of lymphoma, and myeloma.
What are the differences: cancer cells vs healthy cells
There are many factors that can be used to differentiate between cancer cells and healthy cells. It is these characteristics that make cancer a deadly disease.
- Unlike healthy cells, cancer cells grow even when they don’t receive signals to grow.
- Cancer cells ignore signals that tell them to undergo apoptosis, the process of cellular death.
- They can invade and spread to other areas of the body, whereas healthy cells stop spreading upon encountering other cells.
- Cancer cells encourage blood vessels to grow towards tumours, allowing tumours to receive a direct supply of nutrients.
- The immune system removes damaged cells, but cancer cells have the unique ability to hide the immune system.
When cancer spreads to another part of the body, it is called metastasis. In metastasis, cancer cells leave the place they were formed and travel through the blood or lymph system to form tumours in other parts of the body.
Metastatic cancer is identified by the same name and place where the cancer cells originally developed. For example, lung cancer that forms a metastatic tumour in the brain is called metastatic lung cancer as opposed to brain cancer.
What are the main treatments?
The three most common treatments for cancer are surgery, chemotherapy and tradition. They are not always effective and can have lasting effects on the patient.
- Surgery: There are many times of surgery but depending on which stage the cancer is in, the surgeon will remove the entire tumour, remove some of the tumour to allow other treatments to be more effective, or remove tumours that are causing pain to ease cancer symptoms.
- Chemotherapy: This type of treatment uses drugs to stop or slow the growth of cancer cells as the target cells that grow and divide quickly. Chemotherapy can be used to treat cancer, decrease the probability of it returning, stop/slow its growth, or shrink tumours that cause pain.
- Radiation: It is a cancer treatment that applies high doses of radiation to kill cancer cells and shrink tumours. Note that radiation can also damage healthy cells near the tumour.
Although there are other treatment options, these are the most commonly used in cancer patients. They are also combined to provide more effective and personalized treatment.
Recent breakthroughs and research
Here are three important discoveries that were made by scientists in 2020:
- Clinical trials for a cancer vaccine are in the near future: After a recent research breakthrough, Professor Kristen Radford in Australia, and her team are looking to start clinical trials within the next three years. The vaccine acts more like a treatment, preparing the immune system to recognize a molecule commonly found in many types of cancer. Read more about it here.
- A promising treatment approach has been discovered to increase survival for the most common type of childhood brain tumour: Cancer researchers from across the world collaborated to discover that using immunotherapy along with a drug called TNF (tumour necrosis factor) could get rid of tumours that were alternately unaffected by immunotherapy. Although this research is still in its early stages, it plays a major part in increasing survival for patients with medulloblastoma, the most common type of childhood brain tumour. Click here to learn more about this ground-breaking discovery.
- Research shows that a new drug holds the possibility of becoming one of the first targeted treatments for triple-negative breast cancer: Breast cancer is responsible for around 685 000 annual deaths which is equivalent to about 13% of all cancer-related deaths. Triple-negative breast cancer is a type of breast cancer that is especially aggressive. There are no current targeted treatments; however, Dr. Najoua Lalaoui, a scientist at the Walter & Eliza Hall Institute of Medical Research in Australia, has been studying a new drug called birinapant. Her research reveals that birinapant could become one of the first targeted treatments for triple-negative breast cancer. Click on the video below for an interview with Dr. Najoua Lalaoui and more information about her recent discovery.
Key takeaways
- Cancer is a deadly disease in which some of the body’s cells grow uncontrollably and generally spread to other parts of the body. It is caused by changes in genes.
- It can cause tumours, which are lumps of tissues, to form. These can be benign (non-cancerous) or malignant (cancerous).
- Cancer spreads through metastasis, a process where cancer cells leave the place they were formed and travel through the blood or lymph system to form tumours in other parts of the body.
- The most common forms of treatment include surgery, chemotherapy and tradition. These can be combined for personalized treatment.
- Research for more effective treatment is ongoing and advancements are being made including the possibility of clinical trials for a cancer vaccine in the near future.
Explore further
Ideas about understanding, preventing and ending cancer. https://www.ted.com/topics/cancer
Cancer center that explores various aspects of cancer.
https://www.webmd.com/cancer/default.htm
National Cancer Institute for more information about cancer.
https://www.cancer.gov
