Tissue section of human prostate containing adenocarcinoma.
Cell Image Library/Image ID: CD90 01-183C HP eb 400/CC

Cancer is not one disease, but a category of several diseases. It is caused by uncontrolled division of abnormal cells and can occur anywhere in the body.

According to the American Cancer Society, more than one million people are diagnosed with some form of cancer each year in the United States. Cancer has touched the lives of most people worldwide; it can begin in any tissue and start at any age. Cancer is not one disease, nor does it have one cause or one cure. Risk factors include: genetic background; environmental exposure to carcinogens or radiation; lifestyle choices (ex. smoking); and some types of infections (ex. HPV, which is a virus, or H. pylori, which is a bacteria).

Many people, including scientists, hoped that the sequencing of the human genome and easier accessibility to advanced technology would quickly result in an understanding of cancers, leading to a set of cures. However, cancer is a complex phenomenon. Combinations of the risk factors listed above work together to produce (or avoid) the development of cancer, determining the kind of cancer that develops as well as the speed of its growth. Another factor is simply chance, as you will learn from one of our annotated research papers—a tissue with a high rate of cell division is more likely to experience errors leading to mutations. Fortunately, current research is making great progress in the quest to understand and control many forms of cancer.

The Science in the Classroom Cancer collection will help you begin to explore the latest findings in cancer research. It features annotated primary literature about cancer, a hands-on data activity, and other resources from throughout the web.

Featured Resources

Anne Weston/Wellcome Images/Creative Commons
HHMI BioInteractive animation illustrates how mistakes made during DNA replication are repaired. Failure to repair can lead to cancer.