Cancer is a group of diseases characterized by the uncontrolled growth of abnormal, mutated cells that can spread throughout the body.

Metastasis: When cancer cells begin to travel through the body

Metastatic cancer starts in one part of the body and moves to another over time. This is known as metastasis. Such cancers are much more harmful since they attack multiple parts of the body, adapting new metabolic changes to suit the various environments found throughout a body.

Cancer is typically broken down into four stages influenced by tumor size, the presence of cancerous cells in the lymph nodes, and the extent to which the malignancy has spread to other organs in the body.

How does cancer spread through the body?

Cancer usually begins with one tumor, but it can spread to other organs if not removed. This video breaks down how cancer moves to these new areas and why some organs are more likely to get infected than others.

The immune system is in a constant fight to detect and eliminate cellular mutations.

Cells become cancerous if checkpoints in the cell cycle are damaged

Before cells divide, a protein called p53 can halt the cell cycle if damaged DNA is identified, preventing the fault from propagating to daughter cells. If p53 and other tumor-suppressing molecules cannot function due to mutations or other instabilities, damage can accumulate over successive generations until nothing stops cells from dividing uncontrollably, creating tumors.

There are hundreds of subtypes of cancer, making a universal cure nearly impossible.

Why don't we all have cancer?

The creation of a single cell produces 120,000 genetic mutations that can lead to cancer. This video investigates how our bodies proofread and autocorrect those mistakes.

Immunotherapy focuses on boosting the immune system to fight cancer

The immune system detects and destroys abnormal cells, curbing the growth of many cancers. Immunotherapy works to boost the body’s immune system to target and kill cancer cells. There are many ways to accomplish this, including adaptive cell therapy, checkpoint inhibitors, vaccines, and monoclonal antibodies.

Many cancers arise from genetic mutations inherited from your parents

These mutations may happen in response to environmental or lifestyle factors, or may be passed down through family members. Genetic testing can be important in catching certain family cancers early and ensuring patients receive the right treatment for their disease.

Large animals like giraffes and elephants have evolved unique cancer defenses.

The term 'cancer' is roughly 3,000 years old and derives from the Greek word for 'crab,' which may refer to how a malignant tumor can feel like a hard shell.

The seven viruses that cause human cancers

Certain viruses have been linked to the development of human cancers. These viruses account for up to 20% of cancers worldwide, causing cancer by interacting with host proteins, proliferating within weak immune systems, and commandeering susceptible human cells. Unlike other viruses, human tumor viruses don't kill host cells, allowing them to establish persistent infections. The seven viruses include the Epstein-Barr Virus, the Human Papillomaviruses, and more.

Chemotherapy is a cocktail of powerful drugs that slows cancer by interfering with cell division.

Chronic inflammation can cause cellular damage and could lead to cancer

Over time, this cellular defense system can inadvertently damage cells and tissues when it's in this heightened alarm mode over a prolonged period. This occurs because, when immune cells are sent somewhere without a true target, they may attack healthy cells and tissues.

How does cancer actually kill someone?

While the emotional and physical tolls of cancer are often clear, the innerworkings of how cancer kills can be confusing — and terrifying to discuss. Here, oncologists explain how cancer can progress.

What is cancer bioengineering?

While new treatments for cancer are under continuous development, researchers are increasingly using engineering principles to find wholly new strategies to combat the disease. Directions include nanoparticle drug delivery, advanced imaging tools, developing new materials to interact with cells, tissue engineering, robotic surgeries, and more. Such interdisciplinary efforts are expected to unlock new tools and therapies beyond traditional drug formulation.

Explore the differences between healthy and cancerous cells using a DNA microarray

In this simulation, you will learn how scientists use microarrays to experiment on thousands of genes at the same time. By determining which genes are on or off, users can identify those that contribute to cancer formation.

mRNA vaccines alter immune response, not DNA, to combat diseases like cancer.

Changing a single letter in DNA can permanently alter an organism

Genetic mutations occur when cells replicate, which requires a copy of DNA to be created, and involve substituting, deleting, or inserting letters in a cell's genetic code. Mutations can be caused by normal cellular processes, chemical exposure (e.g., carcinogens), or radiation and may result in genetic disorders or genetic variations that drive evolution.

Roughly 1 in 5 cancers are caused by viruses

About 20% of cancers are caused by viruses, with seven specific oncoviruses causing between 10% and 15% of cancers worldwide. These include human papillomavirus and hepatitis B and C viruses, which can lead to diseases such as cervical and liver cancer. Understanding the mechanisms of these viruses is crucial for prevention and treatment strategies.

Patients are a part of the progress

Navigating a cancer diagnosis can be terrifying and overwhelming. There is a robust community of patient advocates dedicated to prevention and diagnosis, research and clinical trials, legislation, needs of individual cancer types, among others. See how patient advocacy improves cancer research leading to improved treatment options and patient care.

Teaching immune cells to fight cancer

CAR T-cell therapy is a type of immunotherapy, which involves strengthening the immune system to attack cancer cells. Patient T cells, which manage immune responses and are responsible for killing pathogen-infected cells, are collected and re-engineered to produce surface-level proteins called chimeric antigen receptors. These CARs, now able to bind to specific proteins on cancer cell surfaces, are multiplied into the millions and infused back into the patient.

Breast, prostate, and lung cancer are the most common forms of cancer.

Low cell division rates in heart cells make heart cancer particularly rare

The heart's location in the chest also offers protection from external cancer-causing factors. The disease affects about 3 in every 10,000 people, though most cases arise from metastasis from other body parts.

Explore the National Cancer Institute's archive on cancer treatments, including complementary and alternative medicine.

What is immunotherapy and how does it work?

Immunotherapy is a type of treatment that harnesses the body's immune system to combat cancer. This video explainer from the American Cancer Society discusses various types of immunotherapies and their roles in targeting cancer cells. Still a new and quickly evoliving field, immunotherapy represents a significant advancement in cancer treatment and offers new options for patients.

Timeline of cancer research milestones

While cancer remains incurable, there's been so much progress in its treatment over the last two decades. Nature provides an abridged history of milestones and major triumphs in cancer research and treatment. Start in the year 2000, and see how much has changed in the first quarter of the new millennium

A new type of immunotherapy focuses on healthy cells hijacked by tumors

Purdue University scientists are at work on a new cancer treatment that attacks immune system cells that feed and protect cancer cells rather than attacking them. The immunotherapy process promises to become a universal treatment for solid tumors. Thus far, the treatment has been tested and shown to work on human tumor cells in the laboratory and animal models.

About 40% of cancer cases are linked to preventable risk factors

Maintaining a healthy weight, engaging in regular physical activity, and consuming a balanced diet can lower cancer risk. Research indicates that about 40% of US cancer cases are linked to preventable factors, including poor diet and inactivity. Understanding these mechanisms empowers individuals to adopt healthier lifestyles for cancer prevention.

See how CAR-T cell therapy works to help fight cancer

Short for chimeric antigen receptor T-cell therapy, CAR-T Cell Therapy helps augment the body's own ability to attack cancer cells. It's a cell-based gene therapy that alters the genes in a person's T cells—which are a type of immune cell—to help them beat back cancerous growths.

Advanced drugs are closing in on cancer's deadliest mutations

The protein KRAS, mutated in many cancers, was deemed ‘undruggable’. Now scientists are hoping to save lives with a batch of new compounds that target it.

The earliest evidence of cancer was found in a 1.7-million-year-old fossil—discovered in the toe of an ancestor of modern-day humans.

Organisms can possess multiple unique sets of DNA in one body

Genetic chimeras can result when cells with different DNA combine, such as when two sperm cells fertilize two egg cells, creating two embryos that then merge. In mosaicism, mutations arise within an organism after conception and can spread through cell division, resulting in diseases and forming genetically distinct anatomy.

Explore more statistics about cancer

The American Cancer Society's Cancer Statistics Center estimates there will be more than 2 million new cancer cases and almost 620,000 cancer deaths in the US during the course of 2025. Breast, prostate, and lung cancers remain the most prevalent. This interactive tool provides detailed statistics on cancer incidence, mortality, and survival rates, allowing users to explore data by state, cancer type, demographics, and risk factors.

Scientists now know that Henrietta Lacks, a Black woman whose 'immortal' cancer cells were nonconsensually sampled and used for research, had been infected with human papillomavirus, a group of pathogens responsible for most cervical cancers.

How medical robots could cure cancer

Medical robots are on the verge of being able to be injected into the body, where they will be responsible for semi-autonomous behavior, such as detecting cancer cells and distributing medication. This six-minute video dives into the science of these nanorobots, which are smaller than blood cells. Applications of these nanobots could range from disease discovery and condition monitoring to tissue repair and artificial blood delivery.

Henrietta Lacks' tumor cells became the first recognized 'immortal' cell line about 75 years ago, but researchers are still investigating the specific mechanisms that enabled the cells to continuously grow and divide in the laboratory.

Tumor genetic profiling can lead to targeted treatments

Genetic profiling of tumors—based on a sample from the tumor, a patient's blood, or both—can help clinicians determine if targeted therapies known to block the growth of certain types of tumors would be appropriate for specific patients.

Somatic expansion, the lifelong growth of specific repeating DNA sequences, is being studied as a potential treatment target for Huntington's disease and other disorders.

Searching for the history of cancer in ancient human bones

Nestled under archaeology lies bioarchaeology, which involves the study of bones, human or animal. This subfield recently birthed another field of study: paleo-oncology. Paleo-oncology looks for cancer and related biomarkers in bioarchaeological remains. This TED article explains how this nascent multidisciplinary field challenges the idea that cancer is modern.

Necrosis is the unplanned death of cells and the tissue they comprise

If cells die prematurely due to a lack of blood flow, injury, or disease, they and their organelles can swell, leading to rupture of the surrounding cell membrane. This releases the cell's contents into the surrounding tissue, causing inflammation and damage to neighboring cells.

Using deep learning to analyze tumors

The explosive growth of life sciences data is driving artificial intelligence methods to gain traction in biology and medicine — including cancer research.

The difference between standard cancer treatments and emerging immunotherapies

If you've ever wondered what the difference was between immunotherapy and chemotherapy, this short video takes you through the steps. Briefly, chemotherapy attacks cancer in tumor cells directly, while immunotherapy encourages your immune system to fight it. There's more to it than that, but this delightful two-and-a-half-minute video provides a good primer.

While most cells possess DNA, red blood cells destroy their nuclei to maximize the amount of oxygen they carry and more easily alter their shape to fit through narrow blood capillaries.

How race science influences breast cancer research

Despite researchers' and physicians' pushback, race is still used in studies and clinics to categorize human differences in health conditions and treatment responses. This article explores how race has influenced breast cancer research. Considering race as a factor in cancer research, diagnosis, and treatment can lead to racial inequalities. Sociocultural factors, including food access and air pollution, greatly influence health outcomes.

Explore global maps of cancer prevalence, with incidences that reflect various risk factors, including smoking rates, HPV infections, sunscreen use, and alcohol consumption.

Gene therapy can occur inside the body, but it can also be completed outside the body—with scientists treating cells in the lab, and then those corrected cells are transplanted back into the body.

The additive effects of smoking, diabetes, and poor diet are the biggest risk factors for developing pancreatic cancer.

'Immortal' HeLa cells—cancerous cells widely used in biomedical research after they were nonconsensually taken from a Black woman named Henrietta Lacks—proliferate easily, causing millions of dollars of damage annually by contaminating lab cell cultures.

Cells cannot grow forever due to escalating inefficiency in transporting chemicals

As cells get larger, their volume grows much faster than the surface area through which nutrients and waste products pass, creating a bottleneck that eventually causes cells to die. This forces nearly all organisms visible to the naked eye to comprise enormous numbers of smaller cells, such as the approximately 30 trillion found in the average adult human.