Cell Division Gone Wrong: Aging and Cancer

Bold words indicate key terms.

What happens to cell divisions as we reach our middle ages? What kinds of problems can this cause in our body?
As we reach our middle ages, there is an increasing number of faulty cell divisions. This can lead to problems such as Alzheimer’s disease, osteoporosis, and heart and kidney failure.
What are aging genes?
Aging genes hundreds of genes that are directly linked to development and aging. These genes related to cellular function and maintenance stop functioning as we grow older.
What are telomeres? How can they provide information about our life spans?
Telomeres are regions of DNA located at the end of each chromosome. They protect the chromosomes from damage during cell division. They get shorter with each cell division, and cells will stop dividing altogether once they get too short.
How is centromere location affected by aging? How does this affect cell division?
When we age, centromeres sometimes do not align properly during metaphase due to missing or malfunctioning proteins. As a result, cell division is stalled until they align, affecting the rate of cell division.
In summary, describe the relationship between old age and cell division.
As you age, cell divisions will slow down, affecting bodily functions.
What is cancer?
Cancer is a group of diseases in which cells grow and divide out of control. This is because of a change in the DNA, leading to failed checkpoints during the cell cycle. Some types of cancer are hereditary while other types are environmental. They are not infectious.
What is a tumour? What is the difference between a benign tumour and malignant tumour?
Tumour is a mass of cells that continue to grow and divide without any obvious function in the body. Benign tumour does not affect surrounding tissues and is not considered cancerous. They may, however, physically crowd surrounding cells and tissues. Malignant tumour interferes with the functioning of surrounding cells and tissues and is considered cancerous.
What is metastasis?
Metastasis is when cancer cells break away from the primary tumour and spread to a different part of the body. They may continue to grow uncontrollably in the new location, forming a secondary tumour.
What causes cancer?
Cancer is caused by mutations in the DNA. Usually, DNA mutations will cause the death of the cell. Other times, they will not affect cell division and are allowed to continue to grow and divide. Rarely, they will affect cell division and cause cancer. Some mutations are caused by carcinogens, which are environmental factors that cause cancer. These include tobacco smoke, radiation, some viruses, chemicals, and other organic solvents. Other mutations are hereditary and are passed on from generation to generation, such as those causing breast and colon cancer.
What is cancer screening? How can it be done?
Cancer screening is checking for cancer even if there are no symptoms. It can be done at home, with a regular medical checkup, or with a special appointment. Those with hereditary genes will prefer to do a genetic screening. Women may do a Pap test by taking a sample of cervical cells to check for cervical cancer. Men may do a self-examination to check for prostate cancer by doing a PSA test (blood test). It is important to remember that cancer screening does not prevent cancer, but the chance to catch cancer early enough to treat it.
What is the ABCD of moles?
ABCD of moles is a self-examination that you can do to check for suspicious moles. A stands for asymmetry. Regular moles tend to be symmetrical in shape and colour. B stands for border. Regular moles tend to have a regular circular border. C stands for colour. Regular moles tend to have one colour. D stands for diameter. Regular moles tend to be small (less than ¼ inch). E is also sometimes used in this test. E stands for evolving. Regular moles do not change greatly over time.
How can you reduce your cancer risk?
Cancer risk can be reduced through lifestyle choices, such as avoiding tobacco smoke, exercise, and a healthy diet (i.e. consuming “superfoods”). Superfoods are high in vitamins, minerals, and antioxidants. Antioxidants protect your body against free radicals (atoms or molecules with unpaired electrons), which can cause cancer and other health problems. Examples of superfoods include broccoli, tomatoes, and carrots (a.k.a. eat your veggies!).
How is cancer diagnosed? Describe the methods.
Cancer can be diagnosed using blood tests or other special imaging techniques such as endoscopy, X-ray, ultrasound, CT scanning and MRI (magnetic resonance imaging).
- Endoscopy: a cable attached with a camera can be inserted into your body
- X-ray: using electromagnetic radiation to check in the insides of your body
- Ultrasound: Using high-frequency sound waves to create digital images
- CT scanning: X-ray done at different angles for a more complete picture
- MRI: using radio waves and a magnetic field to produce a 3D model
If the images or models show abnormalities, then the next step is to take a sample. This can include a blood test or a biopsy where the cancer cells taken from the sample are viewed under the microscope to determine if they are benign or malignant.

What are some treatments for cancer? Describe them.
Cancer can be treated by physically removing the cancerous tissue through surgery. This is usually the preferred method of treatment for simple and accessible tumours. If surgery is not possible, then chemotherapy may be used. This method is usually the first step in treating cancer.

Chemotherapy involves taking drugs to prevent or slow down cell division of cancer cells. This way, they can be removed through surgery or radiation. Side effects of chemotherapy include hair loss, nausea, and fatigue.

A third method is radiation treatment. This targets the tumours specifically and damages them through radiation to prevent cell division. Cancer cells are especially susceptible to radiation.

Lastly, biophotonics may be used to detect and treat cancer. It is the newest method in development and uses beams of light for early detection and targeted treatment.