Somatic Evolution and Mutations with Cancer Cells
Somatic evolution is the accumulation of all the mutations in the cells of an organism throughout a lifespan. Understanding somatic evolution plays an important role in the science of aging and gives insight into the development of cancer (Boland, 2005). “The somatic mutation theory of aging posits that the accumulation of mutations in the genetic material of somatic cells as a function of time results in a decrease in cellular function” (Kennedy, 2011). In other words, as organisms progress through life their cells will ultimately begin to deteriorate due to changes in their genetic material.
Cancer is the term used to describe a group of diseases consisting of hundreds of ailments and although there exists so many different types of cancer, they all begin in a similar way. The body is made up of over a trillion cells, and cancer is the uncontrolled growth of malfunctioning cells in the body (Dawson, 1996). “Normal body cells grow, divide, and die in an orderly fashion. During the early years of a person’s life, normal cells divide faster to allow the person to grow. After the person becomes an adult, most cells divide only to replace worn-out or dying cells or to repair injuries” (American Cancer Society, 2012).
Cancer starts when certain cells in the body are mutated or changed and begin to divide. Cancerous cells grow differently than normal cells, instead of progressing through the normal cell lifecycle, cancer cells continue to grow and create more abnormal cells. A specific trait of cancer cells is that they have the ability to infiltrate and grow into surrounding tissues, developing out of control and causing serious damage to the host (Vincent, 2008). Cells become cancerous when they experience mutation their DNA (deoxyribonucleic acid) and instead of repairing themselves or dying as normal cells would, continue mitosis and produce more clonal cells with this changed DNA (Yachida, 2010).
Stem cells are undifferentiated cells, or cells which have yet to show the morphologic traits they will acquire in the future (Medical Dictionary). Stem cells have the ability to split into specialized cells that are needed in the body, meaning they can serve a wide array of purposes. There are two main types of stem cells: “embryonic stem cells, which are isolated from the inner cell mass of blastocysts, and adult stem cells, which are found in various tissues” (Crosta). With concern to adult organisms, stem cells mainly act as repairers, replacing and replenishing older tissues.
Adult stem cells are thought to be undifferentiated cells that are surrounded by differentiated cells, such as those found readily in tissues, muscles, and organs. The adult stem cells can easily differentiate into the particular cells around them when needed, making them ideal for repairing. They serve as the construction workers of the adult human body, constantly fixing and replacing the cells that malfunction or die....