Stem Cell Research

Stem cells are biological cells found in all multicellular organisms that can divide through mitosis and differentiate into diverse specialized cell types or can self renew to produce more stem cells. In mammals, there are two broad types of stem cells: embryonic stem cells that are isolated from the inner cell mass of blastocysts, and adult stem cells that are found in various tissues. In adult organisms stem cells and progenitor cells act as a repair system for the body; however, in a developing embryo, they can differentiate into all the specialized cells but also maintain the normal turnover of regenerative organs.

Embryonic stem cell lines are cultures of cells derived from the epiblast tissue of the inner cell mass of a blastocyst or an early stage embryo ( usually 3-5 days old). Embryonic stem cells are pluripotent and give rise during development to all derivatives of the three primary germ layers: ectoderm, endoderm, and mesoderm. In other words, they can develop into each of the the more than 200 cell types in the adult body. In July 2008 an update on the subject of stem cell research has a potentially revolutionary development. Japanese researcher Shinua Yamanaka discovered how to take ordinary skin cells from and adult mouse, turn back the genetic clock, and transform them into an equivalent of embryonic stem cells. All research to date has taken place using mouse embryonic stem cells or human embryonic stem cells (both have essential stem cell characteristics but need different environments in order to maintain and undifferentiated state); but, after nearly ten years of research there are no approved treatments using embryonic stem cells.

Adult stem cells, also known as somatic stem cells, are different. They are rare but can be found in a number of tissues including umbilical cord blood. A great deal of adult stem cell research had focused on clarifying their capacity to divide or self renew indefinitely. Adult stem cell treatments have been successful for many years to treat leukemia and related blood/bone cancers through bone marrow transplants. Also the use of Adult stem cells in research and therapy is not as controversial as Embryonic stem cells because their production does not require the destruction of an embryo.

In 1981, scientists discovered ways to derive embryonic stem cells from early mouse embryos. The study of the biology of the mouse's stem cells led to the discovery of a method to derive stem cells form human embryos and grow them cells in a laboratory. Embryos used in these studies were created for reproductive purposes through vitro fertilization procedures. Then in 2006 researchers made a breakthrough by identifying conditions that would allow some specialized adult cells to be reprogrammed genetically to assume a stem cell like state. This new type of stem cells are called induced pluripotent stem cells. Because of their generative abilities, they offer a new potential for treating diseases like diabetes and heart disease. Cells can also now be artificially grown and transformed into specialized cell types using cells that can be taken from a variety of sources like an umbilical cord or blood and bone marrow.

As for treatments, medical researches believe that stem cells have the potential to dramatically change the treatment of human disease. New stem cells therapies exist like bone marrow transplants for leukemia and in the future researches anticipate being able to use technologies from stem cell research to treat a wider variety of diseases like other cancers, Parkinson's disease, spinal chord injuries etc; however, there is a great deal of of social and scientific uncertainty surrounding stem cell research. Once concern of treatment is the possible risk that the transplanted cells could form tumors and have the possibility of becoming cancerous if cell if cell division continues uncontrollably.

Larons Disease and Cancer

Recently on MSNBC.com, Jennifer Welsh posted a article talking about the link between Laron Syndrome and Cancer. The rare disease causes stunt in growth due to a mutation in the gene that codes for growth hormone receptor (GHR), which causes cells to grow and divide. It has now come to scientists attention that those diagnosed with the disease are immune to diabetes and cancer.  Scientists are now trying to harness what causes there immunity and use it to save others from these deadly diseases.

I had my doubts about this article. First of all, with only 250 people infected, the disease seems very rare so I don't think people will be able to get the disease naturally, especially because it is genetically transmitted. This makes the process seem really risky because they would then have to mutate GHR. I don't think many people want to risk their growth hormones to prevent cancer; however, if they are able to obtain the idea of this disease without putting peoples height at risk, then they are definitely taking a step in the right direction.

Despite my doubts about this article, overall it gave me hope.   Even if the research is unsuccessful, they will still end up with more knowledge of cancer then they had before.

Throat Cancer

Throat cancer is a horrible disease with deathly consequences. It traumatizes all of its inhabitants no matter how severe the case, and leave scars that do not fade with time.

Throat cancer is a general term that applies to cancer that develops in the throat (pharyngeal cancer) or in the voice box (laryngeal cancer). The two cancers are often linked together due to fact that the voice box is located directly below the throat. Within the voice box and throat there are more specific types of cancer. Nasopharyngeal cancer is cancer that begins in the nasopharynx or the part of the throat located just behind the nose. Oropharyngeal cancer begins in a part of the throat right behind your mouth, that includes the tonils. Hypopharyngeal cancer begins in the lower part of your throat just above your esophagus and windpipe. Glottic cancer is cancer of the vocal chords. Lastly supraglottic cancer and subgottic cancer begin in the upper (spraglottic) and lower portion (subglottic) of your voice box. Each of the separate types has a link to its own symptoms, some of which include a cough, change in voice, difficulty swallowing, ear pain, sore throat, unintentional weightless, or a lump or sore that doesn’t heal.

Throat cancer occurs when cells in your throat develop genetic mutations, causing cells to grown uncontrollably and continue living after healthier cells would normally die. What causes the mutations is generally unknown but risk factors show a link to carcinogens like alcohol and tobacco.

Carcinogenesis is literally the creation of cancer. Proto-oncongenes are genes that promote cell growth and mitosis. Tumor suppressor genes discourage cell growth or temporarily halt cell decision to carry out DNA repair. What a mutation is to occur in a proto-oncogene (becomes oncogene) damage would be suppressed by normal mitosis control and tumor suppressor genes. One mutation tumor suppresses would not cause caner either because of many backup genes that duplicate it’s functions. Only when enough proto-oncogenes have been mutated into oncogenese and enough tumor suppressor genes are deactivated or damaged signals for cell growth overwhelm the signals to regulate it and cell growth quickly spirals out of control.

One’s risk of throat cancer increases if they smoke or drink alcohol. People who use tobacco and alcohol together are at more of risk then those who use them separately. Some research also suggests that leukoplakia (white patches in mouth) or erythorkplakia (red raised patches in the mouth) may also be throat cancer risk factors. Most throat cancers develop in adults older then 50 and men are ten times more likely the women. Ethnicity may also be a factor with African American men in the U.S. being found to be at a 50% higher risk of throat cancer than Caucasian men.

When it comes to diagnosing throat cancer doctors have several different options. Doctors may use a special lighted scope (endoscope) to get a closer look at throat during a procedure called an endoscopy. And Laryngoscope is another type of scope that can be inserted in your voice box. If abnormalities are found you can pass a surgical instrument through the scope to collect a tissue sample (biopsy). Imaging tests, including X-ray, computerized tomography scans, magnetic resonance imaging, and positron emission tomography may help doctors determine the extent of your cancer beyond the surface of your throat or voice box. Once diagnosed, the next step is to determine the extent or stage of the cancer. Stages help to determine treatment options per patient. Stages are characterized by roman numerals I- IV and each subtype ahs its own criteria for each stage.

Treatment options are then based on many factors: location and stage of throat cancer, type of cells involved, overall heath, and personal preference. Radiation therapy uses high-energy particles like X-rays to deliver radiation to the cancer cells causing them to die. Another option is surgery. Depending on the stage or type of cancer the procedures vary. For cancer that is confined to the surface of the throat or the vocal chords may be treated surgically using endoscopes. For serious cases of throat cancer there are procedure to remove all or part of ones throat or voice box. Other options include: chemotherapy, uses chemicals to kill cancer cells, and targeted drug therapy, which treats throat cancer by altering specific aspects of cancer cells that fuel their growth.

Rehabilitation after treatment for throat cancer is tough. Treatment often causes compilations that may require working with specialists to regain the ability swallow, eat solid foods, and talk. This terrible disease is one that I would wish on nobody, and hopefully one day we will find the cure.

Sources:

http://www.cnn.com/HEALTH/library/oral-and-throat-cancer/DS00349.html

http://www.cancercenter.com/throat-cancer.htm?source=GOOGPHIL&channel=paid%20search&c=paid%20search:google:Google%20-%20Eastern%20Core%20Terms%20New:Cancers:%20Throat:throat%20cancer:Exact&ef_id=2kNM8v5HAAAAOKI:20110211134747:s#risk

http://www.cancer.gov/cancertopics/types/throat

http://www.nlm.nih.gov/medlineplus/ency/article/001042.htm

http://www.wrongdiagnosis.com/t/throat_cancer/stats.htm

Photosythesis

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Better Then Revenge- Cellular Respiration Song

This week we had to create a project on cellular respiration. My partner and I, decided to take a song and change the lyrics to create an awesome song about cellular respiration. After trying out a few songs we decided that we would use Better Then Revenge by Taylor Swift from her Speak Now album. We sat for an hour and a half, through our double bio class, and created this new song. Actually completing the task was much harder to do then we thought. We hope you enjoy our song, we had a ton of fun writing it.

The Krebs Cycle

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Glycolysis SketchFu

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