A Short Note On The Biology Of Retinoblastoma

Cancer is a genetic disease caused by certain changes to genes that control the way our cells function, especially how they grow and divide. Genes carry the instructions to make proteins, which do much of the work in our cells. Certain gene changes can cause cells to evade normal growth controls and become cancer. Genetic changes that promote cancer can be inherited from our parents if the changes are present in germ cells, which are the reproductive cells of the body (eggs and sperm). Such changes, called germline changes, are found in every cell of the offspring. In general, cancer cells have more genetic changes than normal cells. But each person’s cancer has a unique combination of genetic alterations.

Glioblastoma is the most common and aggressive form of malignant brain cancer in adults. On average, 8 of every 100,000 people in the U.S. are diagnosed with glioblastoma every year – representing approximately 2% of all cancers diagnosed [1]. Glioblastoma tumors form when astrocytes, star-shaped cells which support and protect the brain, re-enter the cell cycle and start to rapidly divide. Because the brain is supported by a large network of blood vessels, tumors grow quickly and are difficult to remove surgically. Present treatments for glioblastoma are limited to surgery, radiation therapy, and chemotherapy; however, despite these interventions tumors are likely to regrow. Consequently, typical survival time following glioblastoma diagnosis is less than 2 years.

     Recently we have been studying genetic disorders. We were given the opportunity to choose what genetic disorder that we wanted to learn more about by writing a paper about the disorder. The topic at hand is one that hits close to home to everyone at Milford High School. In a recent, disappointing, and discouraging loss, Milford lost one of its own members of its student body to this serious disorder. Rhabdomyosarcoma is a soft-tissue cancer that grows in the muscle cells of young adolescents. The disorder is a disease in which malignant cells begin growing in muscle tissue. Rhabdomyosarcoma is a type of a sarcoma, which means a cancer of the bone, soft tissues, or connective tissue (e.g., tendon or

What are the most common genetic/chromosome changes related to this form of cancer? Which genes are responsible? Where are these genes located? How are the genes different from normal individuals?

Many sporadic melanomas are also found to have mutations or loss of expression of this tumor suppressor gene, known to act in the same signaling pathway as the retinoblasma cases (see 3.3 Tumor suppressor genes).

Roi1 is also known as rough eye and it is a dominant mutation which causes abnormal patterns and genomic inversions in the D.melanogaster eye (Chanut et al. 2002). The recombination map location of the Roi1 is 2-54.7. The gl3 is an allele and the Gl1 is a protein for the gl gene, also known as glass, both are located at 3-63.1. The gl gene is known to reduce the size of the adult D. melanogaster eye. Even though the gl3 is a weak allele for the glass gene it produces a really pigmented eye ( Ma et al. 1996). The rh1 gene is known as rhodopsin; the recombination map location is at 3.66.4. Rh1 causes degeneration of the D. melanogaster retina (Kristaponyete et al. 2012). Rho1 also known as the rhomboid gene, is closely related to the roughed (ru); which happens to be a recessive eye mutation (Wasserman

A permanent change in a gene that can be passed on to children. The rare, early-onset familial

Retinitis pigmentosa is a group of inheritable diseases that is characterized by gradual deterioration of the photoreceptors in the retina. The photoreceptor cells in the retina, rod cells, are light sensitive cells that are able to sense low levels of light. The frequency of retinitis pigmentosa is one in four thousand births (Deng et al., 2015; Fahim et al., 2012; Haddad et al., 2016; Shu et al., 2012) People affected by retinitis pigmentosa will typically exhibit symptoms of night-blindness first, and this will precede a loss in the patient’s visual acuity field that starts from the outer edge and gradually moves inward resulting in a much smaller visual field and loss of peripheral vision, also known as tunnel vision (Haddad et al., 2016).

Retinitis Pigmentosa (RP) is one of such currently untreatable causes of blindness. RP, along with Age Related Macular Degeneration (AMD) are amongst the more frequent causes of blindness in the developed world (Greenwald 2009), while RP itself is the leading cause of inherited blindness (Palanker 2004).

Neuroblastoma was Dr. Audrey Evan’s main point of medical research, which is one of the most common cancers in children and the most common in infancy. Neuroblastoma is a

Age-related macular degeneration (AMD) is the leading cause of blindness for people 60 years of age and older in the developed world. Vision loss is caused by the destruction of the cone photoreceptors, located in the macula, that are responsible for color/central vision. The underlying cause of AMD is the loss of the monolayer of pigmented epithelial cells located just below the photoreceptors, known as the retinal pigmentum epithelium (RPE). The main role of the RPE is to maintain the function of the photoreceptor layer by secreting nutrients, absorbing stray light, and recycling debris used during the visual cycle. As a person ages the efficiency of the RPE layer is diminished causing a build up of toxic by-products. These toxic build-ups, known as drusens, result in the separation and death of the photoreceptor and RPE layers. AMD is speculated to result from as many as 20 different genetic mutations and as a result there is no known cure for the disease (CITE), but recent advances in stem cell therapy is a hopeful step in the right direction.

Only 200-300 cases exist yearly in the United States. Retinoblastoma occurs in children, averages at about 18 months of age, and is given through heredity, so the only two known known risk factors are age and inheritance. Since retinoblastoma has to do with genes, there is no way to fully prevent it. There are ways to avoid passing it down to the children of the patient, such as consulting gene specialists. They can figure out the chances of the child receiving the cancer and can go over their options. There is a procedure called an embryo implant which ensures that the child won't get the cancer, because the developed eye is replaced with the unaffected

These CNS tumors have complex morphological features with many sources citing that the histiogenesis is uncertain about their cells of origin. The 2006 text Tumors of the Eye and Ocular Adenexa states that these tumors are capillary hemangiomas and are “endothelium-lined capillaries interspersed with pale, vacuolated stromal cells” and that these stromal cells are “believed to be astrocytes that have imbibed plasma lipids.”2 In 2008, the Intraocular Tumors: An Atlas Textbook 2nd Edition reports that “[t]here is little information available about the pathology of this rare neoplasm. It is a diffuse vascular mass composed mostly of small-caliber vessels believed to be derived from endothelial cells of uveal blood vessels.”3 The 2011 Eye Pathology: An Atlas and Text 2nd Edition, states that these retinal hemangioblastomas are “composed of capillaries

Retinoblastoma is a cancer that develops in the retina. The retina is a thin layer of nerve tissue in the back of the eye that senses light and sends signals to the brain to interpret what you are looking at. Retinoblastoma can occur in one or both eyes, and in some cases can spread to different parts of your body. Retinoblastoma can occur at any age but about 200 to 300 children in the United States get diagnosed each year. Retinoblastoma “usually occurs in children younger than 5 years and is most common in children younger than 2 years” (National Cancer Institute). One symptom of retinoblastoma is a white pupillary reflex. This is the most common early sign of retinoblastoma. You can tell that is happening when you shine a light at the eye.

     There are two types of Macular Degeneration. Juvenile Macular Degeneration affects the central vision in young children. This takes place in the macula, or the central region of the retina. The retina is where we are able to read and to distinguish colors. The main symptoms