Professor explains: why people get cancer, how it spreads, and how to prevent it

Cancer is one of the most significant health challenges facing humanity today.

It affects people across all demographics, regardless of age, gender, or socioeconomic status.

Despite its devastating impact, advancements in research and treatment have brought new hope.

In this post, we’ll explore how cancer originates, how it spreads, and what can be done to prevent it.

What is Cancer?

At its core, cancer is the result of abnormal cell growth. The human body contains approximately 30 to 40 trillion cells, each functioning like a tiny community member in a highly organized system.

These cells work together to maintain bodily functions, from digestion to immune defense. However, when this harmony is disrupted, cancer can emerge.

Cancer does not discriminate. It affects the young and old, rich and poor, and people from every ethnicity.

In 2020 alone, nearly 20 million people were diagnosed with cancer globally, and 10 million lost their lives to the disease.

While progress has been made in reducing cancer-related mortality, it remains a formidable challenge.

How Does Cancer Originate?

To understand cancer, it’s essential to grasp the basics of our cellular structure and function:

DNA and Genes:
- DNA is the blueprint of life. Each cell contains chromosomes made up of DNA, which is further divided into genes. Think of DNA as a city’s road system, with genes being individual streets. Mutations in these genes can disrupt normal cellular function.
Cellular “Control Systems”:
- Imagine each cell as a car with a brake, an accelerator, and a fuel system:
  - Brakes (Tumor Suppressor Genes): These genes prevent cells from growing uncontrollably. A mutation here removes this vital safety mechanism.
  - Accelerator (Oncogenes): When these genes are mutated, they cause cells to multiply rapidly, much like a car stuck with its accelerator pressed.
  - Fuel (Telomerase): Normal cells have a clock that limits their division. Cancer cells, however, turn on an enzyme called telomerase, which acts as an endless fuel supply, allowing them to divide indefinitely.
The Role of Age:
- Cancer is often considered an age-related disease. As we live longer, our cells accumulate more mutations, increasing the likelihood of cancer developing later in life.

Types of Cancer

Cancer is not a single disease but a collection of related conditions. It can be categorized into three main types:

1. Sporadic Cancer

This type is caused by lifestyle factors such as smoking, diet, alcohol consumption, and environmental toxins.

2. Hereditary Cancer

Some individuals inherit genetic mutations from their parents, predisposing them to certain cancers. However, inheriting a mutation doesn’t guarantee the development of cancer; it merely increases the risk.

3. Familial Cancer

This type results from a combination of genetic predisposition and environmental influences.

How Does Cancer Spread?

Cancer begins when one cell in the body becomes rogue, but its impact grows as it spreads. This process, called metastasis, involves the following steps:

Breaking Cellular Bonds:
- Most cells are anchored to one another and to their surroundings. For cancer to spread, these bonds must be broken.
Epithelial-to-Mesenchymal Transition (EMT):
- This phenomenon allows stationary cells to become migratory, enabling them to invade other parts of the body.
Creating Tumor Stem Cells:
- Research has shown that metastatic cancer cells often behave like stem cells. These cells are not only migratory but also resistant to treatment, leading to relapse and tumor recurrence.

The Role of Genetics and Environment

Mutations in specific genes, such as BRCA1 (famously associated with Angelina Jolie), can increase cancer risk. However, genetic factors are not the sole contributors. Environmental influences like pollution, smoking, stress, and poor diet also play a significant role.

Stress Management: Chronic stress can weaken the immune system, making the body more vulnerable to cancer.
Microbiome Health: The human body hosts around 38 trillion bacteria, which are crucial for overall health. Disrupting this balance can have serious consequences.

Advancements in Cancer Treatment

The field of oncology has witnessed remarkable progress in recent years. Here are some notable developments:

1. Precision Oncology

This approach tailors treatment to the patient’s specific genetic mutations. By sequencing a tumor’s DNA, doctors can identify targeted therapies that are more effective and less harmful.

2. Immunotherapy

Spearheaded by researchers like Jim Allison, immunotherapy has transformed the treatment landscape. By blocking the signals that cancer cells use to evade immune detection, this therapy empowers the body’s immune system to attack tumors.

3. Innovative Diagnostics

New technologies are making cancer screening less invasive and more accessible:
- Ingestible Cameras: These small devices provide detailed images of the digestive system.
- Smart Toilet Seats: Designed to analyze urine and detect abnormalities.

4. Digital Twins

By combining genomic data with wearable technology, scientists can create a “digital twin” of a patient. This virtual model helps predict the best treatments and monitor progress.

Prevention and Early Detection

The best way to combat cancer is to prevent it or detect it early. Here are some actionable steps:

Adopt a Healthy Lifestyle:
- Avoid smoking and excessive alcohol consumption.
- Maintain a balanced diet rich in fruits, vegetables, and whole grains.
- Exercise regularly.
Regular Screenings:
- Early detection significantly improves survival rates. Tests like mammograms, colonoscopies, and Pap smears can identify cancer at an early stage.
Reduce Environmental Exposures:
- Minimize contact with pollutants and carcinogens.
Support Your Microbiome:
- Consume probiotics and avoid unnecessary antibiotics to maintain a healthy bacterial balance.
Manage Stress:
- Practice mindfulness, yoga, or other stress-reduction techniques.

A Collaborative Effort

Fighting cancer requires teamwork. At institutions like the Legorreta Cancer Center at Brown University, experts from various fields—pathologists, clinicians, and researchers—are working together to develop new treatments and strategies.

Conclusion

Cancer is a complex and challenging disease, but the future is brighter than ever. With advancements in technology, precision medicine, and a collaborative approach, the fight against cancer is gaining momentum.

Early detection and prevention remain critical, and public awareness plays a vital role.

Together, we can make cancer a curable disease. Support research, participate in clinical trials, and spread awareness. Remember, cancer is no longer a death sentence if caught early. Take charge of your health and encourage others to do the same.

Thank you for taking the time to understand this critical topic. Let’s work together to create a healthier, cancer-free world.