What is Cancer?
Genes are units of DNA that code for a specific trait or characteristic. The DNA is coiled and condensed into chromosomes that are located in the nuclei of cells.
Cancer is a term used to describe a wide range of various diseases. However, all types of cancer have one thing in common: cancer causes uncontrollable replication of the body's cells that can spread and harm surrounding tissues. Investments are made in cancer research in order to understand how cancer occurs and why it is so harmful to the body. This research is crucial in order to develop new treatments and provide patients with the best management and care solutions.
In order to understand cancer, it is important to understand how a healthy cell can become a harmful cancer cell. A cell becomes cancerous when it develops 8 specific traits, known as the 8 Hallmarks of Cancer.
A healthy cell has a lifespan similar to our lifespans. They are created, perform certain tasks, divide in a controlled manner, and die when the time comes. All cells contain DNA, the genetic code of all living things. Within DNA exists various genes that contain instructions for different cellular functions. For example, if DNA is a cookbook, genes are the recipes that contain instructions for a specific protein.
The functions of a cell are often guided by biological pathways. These pathways contain several steps that may lead to different outcomes such as the creation of a cellular product or turning genes on and off in a cell. Cellular components must work together to insure healthy cells for a healthy body. Cells work as a network and cannot function by itself. Cells receive internal and external stimuli such as stress or injury and respond to these stimuli by sending and receiving signals through biological pathways. The way we respond to the world is largely dictated by biological pathways. These pathways can control simple tasks such as getting up from a chair and more integrated functions such as response to medications.
The characteristics that healthy cells acquire that transforms it into a cancerous cell are called the Hallmarks of Cancer. The Hallmarks of Cancer include these eight characteristics:
- Sustaining Proliferative Signaling
- Evading Growth Suppressors
- Resisting Cell Death
- Enabling Replicative Immortality
- Inducing Angiogenesis
- Activating Invasion and Metastasis
- Reprogramming of Energy Metabolism
- Evading Immune Destruction
Cells come with a built-in defense system that protects the cell from uncontrolled cell division. Due to this protection, chemicals that interfere with just one of the Hallmarks of Cancer do not have a high chance of causing cancer. However, when chemicals are able to interfere with multiple Hallmarks of Cancer, they can overcome the cell’s defense system. This can lead to uncontrolled cell division and other harmful effects of cancer. When harmful chemicals interact with genes in our DNA, they can cause mutations, a change to a gene. For example, a mutation may promote a gene instructed for cell growth to make even more cells more rapidly. A mutation may also inhibit a gene instructed to control cell growth so that cells are allowed to divide abnormally. These mutations and changes in genes are what ultimately dictates the transformation of a healthy cell to a cancerous cell.
The eight Hallmarks of Cancer are synonymous amongst all cancers. However, the way in which the hallmarks affect different types of cancer are extremely different. A signal sent through a biological pathway can kill one type of cancer while allowing a different type of cancer to prosper.