On average, as many as over six billion somatic cells are divided in the body daily to replace those that are dead or have been damaged. This is done in a precise and appropriately structured manner- at least it seems to go down like a well co-ordinated routine.
However, sometimes something goes wrong, and this is when cancer can occur is when something goes wrong. We have to take a look at how cells usually divide and what happens with this process in cancer.
What is the cell cycle?
Visualizing the cell cycle as a recipe can work—cell copying involves following a recipe to achieve another copy of itself. Indeed, just like baking cakes requires a set of things done in a particular sequence, cells must follow those steps to divide properly; every stage has an important function.
The whole process is like a factory production line. First, the cell grows and ensures it has everything it needs. Then, it copies its DNA (the instruction manual that tells the cell what to do). Finally, it splits into two new cells. This happens repeatedly throughout our lives.
Why do cells need to divide in the first place?
Our bodies wear out constantly and replace old cells. Think about your skin. The outer layer sheds and replaces itself with new cells constantly. The same thing happens inside your body, too.
Here are some reasons why cells divide:
- To replace damaged cells (like when you get a cut and need new skin cells)
- To help you grow (this is why children get taller)
- To keep your organs working properly
- To heal wounds
- To replace cells that naturally die off
What are the stages of the cell cycle?
The cell cycle has several stages, like chapters in a story. Let’s break them down in simple terms:
- Growth Phase (G1): The cell grows more prominent and makes more parts it needs
- DNA Copying Phase (S): The cell makes an exact copy of its DNA
- Preparation Phase (G2): The cell checks everything and gets ready to divide
- Division Phase (M): The cell splits into two new cells
- Resting Phase (G0): Some cells take a break from dividing
All phases are crucial, and cells have some internal controls or integrated checkpoints that will permit everything to go right before proceeding to further stages.
How do cells come to know when it is time to stop dividing?
A typical cell contains an in-built traffic signal indicating that the cells will stop once during the cell cycle. Like a traffic light in your body. These stop signs come from:
- Chemical signals from nearby cells that say, “Enough cells here already!”
- Physical contact with other cells (when cells touch each other, they usually stop dividing)
- Internal timers that tell cells when they’re too old to divide safely
- Unique proteins that check for damage and stop division if something’s wrong
What goes wrong in cancer cells?
This is where things get interesting – and concerning. Cancer cells are like cars with broken brakes. They don’t obey the standard stop signals.
Instead of following the rules, cancer cells:
- Break through the regular checkpoints
- Ignore the stop signals from other cells
- Keep dividing when they shouldn’t
- Don’t die when they’re supposed to
It is like having the photocopier that continues to photocopy without paper and even if its button is switched off.
How does a normal cell evolve into a cancerous cell?
They do not simply lay dormant and one fine morning decide to turn into cancer cells. It usually takes several mistakes (mutations) in the cell’s DNA. Think of it like a car’s safety system:
One broken part might not cause an accident, but if several safety features fail, you could have serious problems. The same thing happens with cells. Several things usually have to go wrong before a normal cell becomes cancerous.
What is Cancer Cell Mitosis?
The process by which the cell divides to form two ‘like’ daughter cells resembling the parent cells. It plays a significant role in the broad range of activities embracing growth, development, and tissue repair. Mitosis is uncontrolled in cancerous cells, leading to an unregulated rise in abnormal cells.
The Stages of Mitosis
The mitosis process has four stages: Prophase, Metaphase, anaphase and Telophase. They occur side by side to each other and at this stage known as prophase when the DNA within the cell solidifies into distinct structures, the chromosomes. During metaphase, the chromosomes start aligning in the middle of the cell. In anaphase, those chromosomes get pulled toward opposite ends of the cell. Finally, the cell begins to split during telophase, with two new nuclei forming around the separated chromosomes.
Differences in Cancer Cells
Mitosis is checked at many levels in healthy cells to ensure everything goes right. When mistakes are detected, though, the cell may autocorrect or even be provoked into a type of programmed cell death called apoptosis, often just called apoptosis. Checkpoints are usually avoided in cancerous cells, permitting cells to divide incessantly. Unchecked proliferation gives rise to tumors which may invade neighboring tissues and spread throughout other parts of the body.
The Impact of Uncontrolled Mitosis
In a very short period, when cancerous cells multiply rapidly, the cancer cells may even conquer normal body functions. Multiplying these cells will disturb the healthy cell balance in the body, creating various symptoms and complications. It’s essential to know the mitosis of cancerous cells so that there may be targeted therapy that could be interrupted in such a way as to stop the multiplying process of cancer to provide better outcomes for a patient.
Why can’t our body’s defense keep cancer from our body?
Our bodies have many ways to prevent cancer. Think of it like a city’s security system with police, security cameras, and alarm systems. Our bodies have:
- Natural cell death programs that remove damaged cells
- Immune system cells that patrol for unusual activity
- Repair systems that fix damaged DNA
- Checkpoint proteins that stop damaged cells from dividing
But sometimes, cancer cells become very clever at avoiding these defenses. They can hide from the immune system or turn off the natural death programs. It’s like criminals finding ways around security systems.
How do scientists study the cell cycle?
Scientists have many clever ways to study how cells divide. They use very powerful microscopes to watch the cells divide right in time. These microscopes also use special dyes lit at different places in a cell, which can increase understanding of how it works.
Understanding normal cell division is essential to understanding how cells could go wrong in cancer. This knowledge leads to better treatments.
What new treatments are being developed based on cell cycle research?
Understanding the cell cycle has led to many new cancer treatments. Some new medicines target specific stages of cell division, while others try to repair the broken stop signals in cancer cells.
Some exciting new treatments include:
- Medicines that block cancer cells from dividing
- Drugs that help the immune system recognize and destroy cancer cells
- Treatments that force cancer cells to die naturally
- Therapies that fix damaged checkpoint systems
How does this knowledge help doctors treat cancer?
Knowing about the cell cycle helps doctors in several ways:
- They can choose treatments that work best for specific types of cancer
- They can understand why some treatments work better than others
- They can predict how different cancers might behave
- They can develop new ways to stop cancer cells from growing
What can we learn from studying normal and cancer cell division?
Studying how cells divide teaches us important lessons about health and disease. We learn that:
- Our bodies are incredibly complex and usually work very well
- Slight changes in cellular division can affect significant times over our lives
- Cancer isn’t a single disease – it is many different diseases
- The understanding of normal cell division is the key to cancer treatment
How can an understanding of the cell cycle help prevent cancer?
Knowledge is power in the case of preventing cancer. Understanding how cells divide helps us:
- Make better lifestyle choices that protect our cells
- Recognize early warning signs of cancer
- Understand why certain things increase cancer risk
- Develop better screening tests for different cancers
Cancer prevention knowledge is not restricted to scientists and doctors alone but to everyone. Understanding the workings of our cells puts us in a better decision-making position regarding our health.
The Takeaway:
Cancer may seem frightening but remember that scientists and doctors learn more about it every day. Each discovery regarding how cells divide brings us closer to better treatments and maybe even cures for different types of cancer. The more we understand normal cell division, the better we are equipped to fight cancer when things go wrong.
Remember, your body is fantastic at keeping cells dividing normally. While cancer can happen, your body has many natural defenses against it. Understanding these processes helps us appreciate how remarkable our bodies are and how we can help them stay healthy.
REFERENCES:
https://www.nature.com/scitable/topicpage/cell-division-and-cancer-14046590/
https://cancerquest.org/cancer-biology/cell-division
https://www.pnas.org/doi/10.1073/pnas.94.7.2776
https://cancer.ca/en/cancer-information/what-is-cancer/how-cancer-starts-grows-and-spreads
https://www.sciencedirect.com/science/article/abs/pii/S0344033823005551
https://blog.dana-farber.org/insight/2023/05/what-is-the-cell-cycle-and-how-is-it-related-to-cancer/