what are the mechanisms a cancerous cell takes to prevent apoptosis.?
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It's pretty well established that the apoptotic machinery gets deprogrammed by cells progessing through tumorogenesis.  One way is the well understood p53/Mdm2 pathway.  P53 is a tumor supressor and, upon DNA damage, can either halt cells to repair the damage (at the G1/S checkpoint) or trigger apoptosis.  It does this by promoting gene expression.  \n\nAnother mechanism is to inhibit t-cell induced apoptosis, by deregulation of FasL and other proteins.\n\nThere's a whole bunch of info in the Cancer Medicine book online at NCBI (below).
611572
A disease marked by the uncontrolled growth of cells, often with invasion of healthy tissues locally or throughout the body. Cancer is the second leading cause of death in the U.S, after the cardiovascular diseases. In 2003 the American Cancer Society estimated that about 560,000 Americans died of cancer, and twice that number were newly diagnosed with one form or another of the disease. The most common cancers in the U.S. are lung, breast, colon, prostate, and skin. Because most cancers occur in patients who are age 65 or older, the incidence of cancer is expected to increase as the population ages. More than 200 kinds of cancer have been identified. Cancers that arise from epithelial tissues are called carcinomas; from mesenchymal tissues, sarcomas; from lymphatic cells, lymphomas; from blood-forming cells, leukemias. Cancer cells have several reproductive advantages over normal cells. They can make proteins that stimulate their own growth or that stimulate new blood vessels to bring them nourishment. They can produce enzymes that prevent their chromosomes from aging. They can invade the bloodstream and find places to grow in new tissues. Usually, as cancer cells proliferate, they become increasingly abnormal and require more of the body's metabolic output for their growth and development. Damage caused by their invasion of healthy tissues results in organ malfunction, pain, and, often, death.
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The following  website  contains all valid reasons for  cancer.\n\nhttp://www.cancerhelp.org.uk/help/default.asp?page=122\n\nhope it satisfies your query.\n\nRegards\n\nParadiso
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Not Caused By What The Above Has Posted........Cells normally grow and divide to produce new cells, as the body needs them. With BPH an excess of normal cells is gradually formed in the prostate, but with cancer the cells become abnormal. They keep dividing out of control forming a tumor. They can invade and destroy nearby healthy tissue and, at later stages, can break away from the tumor and enter the bloodstream and lymphatic system to spread to other parts of the body.With prostate cancer this mainly involves the bones, bladder, rectum and other organs. No one knows what causes cells to become cancerous, or malignant, but research is looking into various causes. It seems to involve an interaction between a man’s genetics and his environment. Certain factors, called risk factors, have been associated with a greater chance of developing prostate cancer, but it is not known if reducing or avoiding these factors can prevent prostate cancer.
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The above response addressed positive advantages; as for disadvantages:  When defective apoptotic processes occur, an extensive variety of diseases can result. Too *much* apoptosis causes cell loss disorders, whereas too little results in uncontrolled cell proliferation [read: cancerous tumors].  As outlined on Wikipedia -"Apoptosis can occur, for instance, when a cell is damaged beyond repair, or infected with a virus. The "decision" for apoptosis can come from the cell itself, from its surrounding tissue or from a cell that is part of the immune system.  If a cell's capability of apoptosis is damaged (for example, by mutation), or if the initiation of apoptosis is blocked (by a virus), a damaged cell can continue dividing without restrictions, developing into cancer. For example, as part of the hijacking of the cell's genetic system carried out by human papillomaviruses (HPV), a gene called E6 is expressed in a product that degrades p53 protein, which is a vital piece of the apoptotic pathway. This severe interference in the apoptotic capability of cells plays a critical role in the fact that persistent infection by oncogenic HPVs can result in the development of cervical cancer."  Also, the Hgg protein, which conveys an anti-apoptotic signal, has been found to be overexpressed in pancreatic adenocarcinoma tissues.
949366
cancer is the big one, cancer cells are cells that just don't die, so they grow and reproduce take up valuable nutrients from healthy cells, crowd out healthy cells until the healthy cells die, and finally take over your body until it's systems shut down.
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Oncogenes are mutated genes that contribute to cancer development by disrupting a cell’s ability to control its own growth and DNA repair mechanisms2,5. Normally mitosis (cell division) is a carefully regulated event, requiring the activation of one protein to activate another, in what is known as a signal transduction cascade. This cascade eventually culminates in changes in gene expression that prepares the cell for mitotic events.\n\nOncogenes are mutated forms of proto-oncogenes; these genes are often involved in growth signalling and anti-apoptotic pathways. When proto-oncogenes mutate to become oncogenes they retain their functionality, but are no longer capable of responding to normal regulatory signals (see Figure 1).
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you cna't prevent cancer 100% So many things cause cancer. Genetics, overexposure to radiation and harmful chemicals etc. \nMy advice would to just live a healthy life by eating right and exercising.
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Not exactly. It is more likely that depression and stress weaken your immune system, which then fails to kill cancerous cells. Cells go cancerous in your body all the time, but are killed almost instantly most of the time.
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wow, people who have no clue try to sound like medical experts.  I'm no medical expert, but I can lead you to a better answer.\n\nTelomere immortalization is one known element of cancer, so I'll use that to explain why smoking is a leading cause of cancer, but just know there are several other things that happen besides this.\n\nBasically cancers are cells that grow, bond, and refuse to die.  We're talking about cells that try to become immortal, and you can understand why.  The carbons and chemicals in your lungs actively block oxygen, which your lungs were designed to need.  Every time your body replaces dead cells (which it does constantly), it checks the environment they're in to see if they need to make adjustments.  Oxygen is essential to cell survival, so if you're choking them to death, they'll get desperate.  Some will just die.  Some will go on gasping for air.  But some will rebel from the body, which is killing them, and find their own mission.  And a tumor is born.  These are like lawless vigilantes who don't give a damn about being part of the body anymore.
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Cell division (think CELL CYCLE) is regulated by an incredibly complicated series of genes/proteins and signaling. But in the simplest terms, cells have genes called "oncogenes" and "tumor supressor genes", of which the former causes cell division, and the latter stops cell division.\n\nIn all cells, both of these kinds of genes are functioning all the time, but are regulated by various pathways (by extracellular signaling, and even factors from within the cell). \n\nAn oncogene we know a lot about is called RAS, and a tumor suppressor we know a lot about is p53. Basically in cancer, and this is just two examples: (1) RAS (an oncogene) activity is unregulated, thus the cell loses control of the cell cycle and divides uncontrollably. (2) p53 activity is lost, and thus we lose "tumor suppressor" function, and the cell divides uncontrollably.\n\nThe problems with cancers are not always these genes themselves, but the pathways that regulate them (regulate their transcription for example). There are many many many different things that can upset these pathways, and thats why cancer is so so difficult to fight/prevent.
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Helpful:\n1. treatment of cancer\n2. used to produce electricity\n3. xrays...used for diagnosis\n\nHarmful:\n1. major cause of cancer\n2. radiation poisoning
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Usually death is caused by the body organs failing or shutting down.   This is caused by increased growth of the cancer cells that spread to other organs other than where the cancer is and and cause them not to function properly.  Sometimes this growing or spreading of cancer cells and be slowed down or stopped with medication called CHEMO or by radiation.  Other times CHEMO and radiation are not sucessful  and the disease gets worse and leads to death.
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The title is actually\n\nIntroduction to the Cellular and Molecular Biology of Cancer \n\nYou may be able to access it from http://scholar.google.com\nIf your institution has access you may be able to download it.\n\nIt is also available as a inexpensive paperback
458690
Depending on where the cancer is located, the disease itself may interfere with the gastrointestinal tract or cause imbalances in the body by overproducing or underproducing hormones that control metabolic activities. Cancer cells can produce toxins in the body to make you lose your appetite.  Your body may also be expending a lot of energy trying to fight off the cancer.  It can also be stress related.
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There are many different forms of cancer and many different causes. Cancer develops from mutations in the genes that regulate cell division. The mutations silence the genes that ordinarily monitor replicating DNA for chemical errors. The affected cells have no built in brakes to halt cell division. As the abnormal mass of clees,called malignant tumor, grows, blood bessel form to supply the tumor with the nutrients it needs to support its growth.Eventually, the tumor invades healthy tissue and may metastasize.\n\nBladder cancer is associated with smoking cigs and alcohol.So is mouth, throat and esophagus cancers. Lung-smoking.Liver-infection with hepatitis virus,alcohol,iron overload,toxicity.Kidney and Pancreatic and lung cancer-high intakes of red meat(pan), cig smoking and air pollution.Prostate-high intakes of fats,esp.saturated fats from red meats and possibly milk products.Ovarian-high lactose intake from milk products and oral contraceptive use. Stomach-high intakes of smoke or salt preserved foods, smoking, infection with ulcer causing bacteria or refined flour or starch.Colorectal-high intakes of fat(saturated), red meat, alcohol, and supplemental iron.Low intakes of fiber, folate,viatmin D and veggies.
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Cancer is a condition that occurs when the cells in a person's body don't divide correctly--they don't stop dividing, in fact.  This causes a tumor in the area where the cells are multplying, which can be pretty much anywhere (lung, liver, stomach, breast, testicles, mouth, brain, cervix, skin, etc.).  The cancerous cells in the tumor can spread it to other areas in the body, in a process called metastasis.  \n\nYou can read more about cencer here:\nhttp://cancer.about.com/od/newlydiagnosed/a/whatcancer.htm\nIt doesn't have a lot of medical jargon and gives a lot of good information.\n\nHope this is helpful :-)