Реферат: Conquering Cancer Essay Research Paper Conquering CancerOne
Название: Conquering Cancer Essay Research Paper Conquering CancerOne Раздел: Топики по английскому языку Тип: реферат |
Conquering Cancer Essay, Research Paper Conquering Cancer One of the first scientists to prove that cancer is genetic was Biologist, Dr. Weinburg. In Weinburg s experiment he took cancerous cells from rats brains and mixed their DNA with that of normal cells. The result was that the cells became cancerous, proving that cancer is in genes. In recent years our knowledge about cancer and what causes it has greatly increased. We now know that vital genes mutating cause cancer. Just one mutated nucleotide out of 15,000 can turn what would be a normal cell into a cancerous one. These mutations have been linked to control cells. What scientists believe is that the signal that cells receive from control cells that tell them to divide, is being given without reason. They also think this has to do with the cell having too many receptors. All types of cancer are caused by cells dividing too rapidly or often, this causes abnormal growths. How you obtain a given form of cancer can differ greatly. Smoking, diet, chemicals, etc. can cause cancer or it could just be hereditary. At this point the treatments we have for cancer are vague. Radiation therapy and chemotherapy destroy numerous body cells, and doctors can only hope to kill more bad cells than good. The most effective treatment would be to pinpoint the location of the genetic mutation and cure patients that way. Scientist said at a resent convention that this a focus of their approach to curing cancer. In early experiments with rats they were able to locate the unco genes. Unco genes are the mutated genes that cause cancer. What is far more interesting is that in rats with more aggressive tumors they found more unco genes and in rats with less aggressive tumors they found less unco genes. Also they found in more deadly tumors that there were more receptor on the cells. After finding the information about the number of unco genes and receptors in relationship to the severity of the tumor, treatments were closer to being discovered. In about a year s time scientists were able to manufacture antibodies that would help to reduce the number of receptors. These antibodies find and then stick to excess receptors. This was tested first on mice. They took mice infected by cancer and injected into half of the mice the antibodies, while the other half received nothing. The mice that did not receive the treatment showed dramatic tumor growth, and the mice that did receive the antibodies showed slowed tumor growth. Afterwards the mice that showed slowed growth were taken off the treatment and a lot more growth was very obvious. The next step was to test this antibody treatment on volunteer human patients. In 1991 a woman named Connie signed up for this experimental treatment. Her breast cancer had resisted all other forms of treatment; this is why she decided to try gene therapy. Dr. Slaymen at the UCLA medical center was the doctor who was in charge of this experiment. Since this had barely been tested, Connie only received one dose of 500mg. This also gave scientists a chance to test for side effects. Some of the antibodies she received were radioactively tagged so they could trace the movement of the antibodies. The results of this experiment were very positive. There were no side effects, and most of the antibodies did indeed go to the cancerous cells. Afterwards Connie returned to chemotherapy and showed dramatic progress. Unfortunately there are many other types of cancer and they can not all be treated in the same way. Pat Steeg is a scientist who like many others is devoted to treating and hopefully curing cancer. Her research is focused on what causes the metastasis of cancerous tumors. While studying skin cancer in mice she discovered a gene that might tell if a tumor would spread or not. In cancer that did not spread the NM23 was normal, and in cancer that did spread it was turned off. Mice were injected with cancerous cells that had been altered so that the NM23 was normal and others were injected with cells in which the NM23 was turned off. As Steeg accurately predicted that in the mice with the altered cells the cancerous cells stuck together but in the mice with the NM23 that was turned off the cancer cells spread. With this knowledge we can not cure cancer but it will certainly help in the battle against it. This has been said to be the most exciting time to work in cancer research. We have come so far and we are closer to a cure than we have ever been. Scientists are nearing the ability to pinpoint the locations of many mutated genes that cause cancer, and they can now treat the problem of cancerous tumors spreading. Also many new treatments are being discovered that can help reduce the effect of cancerous cells on the body. Hopefully we will see a cure for this horrible disease soon in the years to come. |