Cancer is a disease that affects people of all nationalities and age groups.
There are many different types of cancers affecting different parts of the
body. A cancer, or tumor, can occur in any organ or tissue of the human body. Solid tumors form lumps, while liquid tumors flow freely in the blood.
All cancers start with mutations in one cell. The mutations are in the cell's DNA and may be inherited. Less than 10% of all cancer mutations are inherited. Usually, the mutation arises as a result of environmental factors.
The DNA mutation may be a single nucleotide change as shown below, or a deletion or duplication of DNA sequence. A change in the genetic sequence can then lead to the production of a mutant protein.
Although in rare cases one mutation is enough, it is usually an accumulation of mutations that irreversibly transforms a normal cell into a cancerous one. As we age, we accumulate more and more mutations; this explains why cancer incidence increases with age.
These mutations can disrupt the cell’s life cycle of growth, proliferation, and death. This leads to the accumulation of more “rogue” cancer cells and the development of a tumor mass.
In 2000, Douglas Hanahan (shown below) and Robert Weinberg published a paper in Cell, "The Hallmarks of Cancer," which identified some organizing principlesof cancer cell development.
Douglas Hanahan, Ph.D.
University of California, San Francisco
We believe that cancer acquires capabilities and that these capabilities are all, to some approximation, necessary to produce a successful tumor. And these may not be a complete description of a tumor but they, probably just in the same way as you describe a car as having a motor and some wheels and tires and a gas tank and some brakes you haven\'t completely described the car, but you\'ve described a lot of the capabilities that allow it to do what it does. So I think the same issue here is that tumors have a set, a minimal set, of capabilities, that we think are necessary, and so we call these the hallmarksof cancer.
Inside Cancer - Multimedia Guide to Cancer Biology, Hallmarks of cancer, Molecule map, Growing uncontrollably, Evading death, Processing nutrients, Becoming immortal, Invading tissues, Avoiding detection, Promoting mutations, Causes and prevention, Smoking, Inheritance, Diet, Mold, Viruses, Sunlight,Diagnosis and treatment, Pathology, Pharmacogenetics, Targeted therapies, Pathways to cancer, At the cell surface, Beneath the membrane, A bevy of interactions,To the nucleus, Inside the nucleus, Making the protein, Releasing the protein.