In today’s quickly growing medical field there seems to be no obstacle that science has yet to overcome. In visits to doctors or hospitals, we explain our symptoms and sure enough a few minutes later we walk out with a prescription in hand. Yet recently the battle against cancer has grown more difficult because ways to treat and cure patients has significantly narrowed. Cancer has become the greatest medical mystery due to inconclusive facts about the disease that remain unresolved. Therefore treatments like chemotherapy and radiation are showing less and less results and it is becoming more evident that cancer is being driven by the selective pressure of natural selection. This is why many scientists and researchers have begun to view cancer from an evolutionary and ecological lens broadening prospects that research is furthering and bringing society closer to a cure. The application of evolution and ecology to cancer is already helping us to better understand, predict and control this disease (Merlo 933.) Being able to look at cancer with a different perspective and approach can lead to countless discoveries and a better understanding of mutant cells that hold the ability to replicate and kill very quickly. The studies of cancer biology through evolution and ecology have brought insight from research as well as brought profound implications in understanding why current cancer treatment are failing and how radically new therapies might now arise.
Historically there has been very little attention that focuses on evolutionary biology and the understanding towards controlling neoplasm cell progression. Tumor cells develop constantly by natural selection and many are thought to continue evolving as they reproduce. The mai...
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...fferent; simply the rate of reproduction of an organism is much slower than a cell. This is why cancer tends to develop so quickly, the irony of cellular selection is that while the cell is evolving benefiting its evolutionary fitness, it happens at the expense of an individual. As further explained by “Another perspective on cancer”, “…cancerous cells have an advantage in comparison to other cells in the body, but are disadvantageous to the organism. Selection at the cellular level might wind up hampering the organism’s survival reproduction, acting in the exact opposition to selection at the individual level (____2.)”
Works Cited
Merlo, Lauren M.F, John W. Pepper, Brian J. Reild, and Carlo C. Maley. "Cancer as an Evolutionary and Ecological Process." Rev. of Evolutionary Theory of Cancer. Nature Publishing Group 6 (2006): 924-33. Academic Search Elite. Web.
The acquisition of an immortalized proliferative potential is very important for human tumors because, otherwise, the tumors will not grow in number nor will they metastasize. Mutations in progenitor cells would not be transmitted too far as they have limited replication and proliferation ability. Thus, the growth of the tumors will be limited. Hence, if there is even a very small population of cells with the ability to proliferate continuously, there will be a source for productions of more cells for the tumor. Clonogenic assays have shown that, though most cells in a tumor have a limited ability to proliferate, a subset of cancer cells exist in these tumors that continuously proliferate and give rise to new tumors on transplantation.
..., while a cell undergoes cell cycle, when a cell comes in contact with another cell, it stops reproducing. However, cancer cells continue to duplicate repeatedly until there is a mass of cells or a tumor to form (see figure 9). Lastly, in cell division when there is a mutation or abnormality in the DNA, a normal cell stops dividing. However, a cancerous cell will continue to duplicate and form mutations (“Cell Biology and Cancer”). Also, cancer cells are harmful because they grow and duplicate with complete disregard to the functions and limitations of the body (see figure 10). Also, cancerous cells have the ability to spread through metastasis throughout parts of the body through the bloodstream. In terms of similar behavior to that of normal cells, cancerous cells also duplicate, but at a very different rate ("Cancer Cells vs. Normal Cells: What's Different?").
...nescence is result of a combination of the antagonist pleiotropy theory, mutation accumulation theory and disposable soma theory. The three evolutionary theories claim that natural selection is weak and ineffective in sustaining reproduction, growth, survival and somatic repair during the post-reproductive years causing genetic diseases in older individuals compared to younger individuals. As biological processes shut down, older individuals develop a weak immune system that can no longer fight the deleterious genes and mutations leading to death. Moreover, the evolutionary theories paved way for new research in gerontology that led to the development of new genetic theories of aging. The definite cause of genetic diseases in older individuals is yet to be determined, but all theories suggest that senescence is an inevitable process that all organisms experience.
Cancer has been an active concern in our society for the past couple decades, since we truly discovered the nature of cancer and the potency it brings along with it. However, it was not until the mid-20th century that scientists were beginning to truly understand the origin of cancer. Scientists dating back all the way to the Renaissance, when they first began performing autopsies to learn more about the human body and form, noticed abnormalities but it never clicked that it was something much worse than it seemed. Research has continued since then, and it has continued to thrive even to this day. When James Watson and Francis Crick discovered DNA and it’s chemical structure in 1962, it opened up doors that even they could not expect. With the understanding of DNA and how it affected the way we look at life, came the beginning of the understanding of mutated DNA (which is a cause of the growth of cancerous cells). In this past century, researching scientists discovered that cancer is linked with the DNA that resides in a cell’s nucleus. By ways of damage to the cells via chemicals or radiation, or even introduction of a new DNA, the cancerous cells begin to form and duplicate. We are learning more and more about cancer and how to fight it, but we still have much more to learn.
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).
The cell cycle is the process by which cells progress and divide. In normal cells, the cell cycle is controlled by a complex series of signaling pathways by which a cell grows, replicates it’s DNA and divides, these are called proto-oncogenes. A proto-oncogene is a normal gene that could become an oncogene due to mutations. This process has mechanisms to ensure that errors are corrected, if they are not, the cells commit suicide (apoptosis). This process is tightly regulated by the genes within a cell’s nucleus. In cancer, as a result of genetic mutations, this process malfunctions, resulting in uncontrolled cell proliferation. Mutations in proto-oncogene or in a tumour suppressor gene allow a cancerous cell to grow and divide without the normal control imposed by the cell cycle. A change in the DNA sequence of the proto-oncogene gives rise to an oncogene, which
Tumors are formed by the alteration of the body’s own cells. This can be caused by environmental factors such as radiation, like UV exposure, chemicals or viruses 1. These can disrupt genes that control growth and cause an increase in cell division and proliferation. Proto-oncogenes are those genes that control normal but essential cell processes that keep cell growth and death in check. Two important categories are apoptosis genes, which regulate cell death, and tumor suppressor genes, which decrease cell propagation 1 . If these genes were mutated to the point where they cannot produce a functioning protein, cell division would continue far past what it was supposed to and unhealthy cells would be allowed to live and continue to multiply. This is what creates a malignant tumor. Certain conditions in the body can also promote the growth of cancer cells. One of these is a deficiency of natural killer (NK) cells, which are able to kill cancer cells by creating a pore in the cell membrane with perforin and releasing granzymes into the cell. Low levels of perforin allow for tumor growth 1. Chronic inflammation can also ...
25% of the deaths h in 1991 and is the most common cause of death
Darwin states that this struggle need not be competitive in nature and also entails a species’ efficiency at producing offspring. Natural selection works not as an active entity that seeks and exterminates species that are not suited for their environment; instead, it retains variations that heighten a species’ ability to dominate in the struggle for existence and discards those that are detrimental or useless to that species. Stephen J. Gould explains the case of r-selection in which a species’ chances of survival are most reliant on its ability to reproduce rapidly and not on its structure being ideally suited for its environment. Gould’s example shows the beneficial results of perceiving natural selection not as something that changes a species in accordance with its environment but as something that preserves characteristics beneficial in the s... ...
An ordinary human body contains approximately one trillion cells and precisely 46 chromosomes in each cell. However, the human body can be altered by a genetic mutation. Over the course of history, genetic mutations have had a large impact on the human race. They have brought harm to numerous amounts of people. Cancer, in particular, is one of the most lethal diseases. Cancer begins when a portion of DNA inside a chromosome is damaged, causing a cell to mutate. Then, the mutated cell reproduces multiple times and creates a tumor. Afterwards, cancer cells break off of the tumor, enter the bloodstream, and disperse throughout the body. If the cells break off, the tumor is considered malignant - this type of cancer is very difficult to cure. Many patients today stay optimistic for a medication to heal cancer. It is imperative to address a few of the causes and effects of cancer in order to gain a general knowledge of genetic mutations.
The East Pennsboro elementary school raised money for a statue at a local park. The statue was a ring of children that were holding hands. There was one child missing; the link was broken. The statue was dedicated to East Pennsboro students that did not make it to their graduation. My sophomore year of high school inspired this piece of artwork.
The American Cancer Society publishes current advances made in cancer research on their website. Many of the exciting discoveries about how best to treat the disease focus on the genetic aspects associated with certain types of cancer. In addition, treatments aimed at genetic solutions to cancer may be more effective and may cause fewer adverse side effects than traditional cancer treatments (American Can...
Cancer develops when cells in a part of the body begin to grow out of
... information needed to stimulate normal cell growth. Failure can lead to the onset of cancer. (Campbell, Reece, Urry, Cain, Wasserman, Minorsky and Jackson, 2008)
Without evolution, and the constant ever changing environment, the complexity of living organisms would not be as it is. Evolution is defined as a process that results in heritable changes in a population spread over many generations (8).Scientists believe in the theory of evolution. This belief is based on scientific evidence that corroborates the theory of evolution. In Figure 1 the pictures of the skulls depict the sequence of the evolution of Homo-sapiens. As the figure shows, man has evolved from our common ancestor that is shared by homo-sapiens. The change of diet of homo-sapiens over time has thought to contribute to the change in jaw structure and overall skull shape.