What Science Knows About Cancer

As you investigate why cancer is a growing problem in the United States and across the globe, explore the burden cancer places on society as a whole - both to people and the economy - and look at some of the most common forms of the disease. See why, surprisingly, cancer doesn't rank on the Global Burden of Disease Study.

What do population studies tell us about the causes of cancer? Define the science of epidemiology and learn how it can be used to study cancer in both populations and individuals. Differentiate between case-control and cohort studies, and the categories of risk factors for cancer.

Continue exploring epidemiology by delving into environmental causes of cancer that have emerged from studies, including tobacco, diet, a woman's reproductive status, medications, pesticides, radiation, and even your personality. How does giving birth later in life make you more vulnerable to breast cancer? Is the average person's exposure to pesticides really dangerous? Find out here.

Take the first steps in understanding the multistage model of cancer by learning how various agents initiate cancer at the genetic level. Explore the fundamentals of DNA as genetic material, the process by which DNA is expressed and duplicated, and the ways this process of duplication can go awry, causing cell mutations to accumulate.

Two types of carcinogens mutate DNA: chemicals and radiation. Build on what you've learned about DNA by looking specifically at how these carcinogens produce cancer at the cellular level. Then, examine carcinogens that don't damage DNA and how epigenetic changes in DNA can result in cancer.

Does hair dye cause cancer? What about saccharin? Familiarize yourself with the types of experiments scientists conduct to determine if something causes cancer, and consider whether a range of natural and manmade substances with carcinogenic properties have the potential to cause cancer in humans. Conclude this lecture by looking closely at the concept of risk analysis.

Focus on cells as the basic structures of living things through an exploration of their internal composition, particularly the nucleus where the genome is retained. See how this discovery was proven in the cloning of Dolly the sheep and consider how this is relevant to cancer treatment.

How do tumors start? Find out how cells divide without normal controls in place and the nine unusual properties shared by many cancerous cells - including the ability to recruit a blood supply. Then learn about the process of apoptosis, or programmed cell death, and the molecules being developed to block telomerase, a protein that lets cancer cells escape dying.

What is the difference between benign and malignant tumors? What signs of cancer do people typically experience? Turn to tumor development and growth with a discussion of the methods doctors use to diagnose, stage, and grade tumors - all of which inform how aggressive treatment should be - and an introduction to the distressing processes of metastasis and angiogenesis.