Throughout history, the ‘ideal’ image of people has changed significantly. People have been expected to look differently over time, with different styles and fads and they have always enjoyed going to the beach and pool, spending time outside and relaxing – including societies’ addiction with tanning. Everyone loves coming back from the beach with a nice, dark tan, however, they don't know the dangers entailed
Skin cancer is the most common type of cancer in the United States. It is the abnormal growth of cells in the skin. There are two different types of skin cancers: Melanomas and non-melanomas. Most skin cancers are the non-melanoma type. There are two main types of non-melanoma skin cancer: basal cell carcinoma and squamous cell carcinoma. Most non-melanoma skin cancers are basal cell carcinoma. It can damage deeper tissues, such as muscles and bones. It almost never spreads to other parts of the body. Squamous cell carcinoma however, is less common. It often develops from a small rough spot that grows into sun damaged skin and can sometimes spread to other parts of the body. Non-melanoma skin cancer is usually caused by too much sun. Using tanning beds or sunlamps too much can also cause it. There are other types of skin cancer that are non-melanoma but these are much less common - they include Merkel cell carcinoma and several kinds of sarcomas.
Melanomas often resemble moles; some develop from moles. The majority of melanomas are black or brown, but they can also be skin-colored, pink, red, purple, blue or white. Melanoma is caused mainly by intense, occasional UV exposure, frequently leading to sunburn, especially in those who are genetically predisposed to the disease. Melanoma kills an estimated 8,790 people in the US every year.
Melanoma, the most lethal form of skin cancer, is responsible for more than 80 percent of all skin cancer deaths and spreads readily to the lymph nodes and other organs. While early stage melanoma is curable, the later vertical growth phase (VGP) is frequently metastatic, with median survival times of less than nine months. Many cancers begin when one or more genes in a cell are mutated (changed), creating an abnormal protein. A person may either be born with a genetic mutation in all of their cells (germ-line mutation) or acquire a genetic mutation in a single cell during his or her lifetime sometimes as a result of exposure to environmental factors, such as UV rays from the sun.
Most melanomas – about 90 percent, are considered sporadic, meaning that the damage to the genes occurs by chance after a person is born, and there is no risk of passing on the gene to a person's children. An increased risk of melanoma occurs when specific gene mutations are passed within a family from generation to generation and is sometimes called familial melanoma.
An inherited risk of melanoma is suspected if two or more first-degree relatives (parents, brothers, sisters) are diagnosed with melanoma. Many people who have an increased risk of melanoma never develop the disease; only 10 percent of melanoma is familial. The non-inherited BRAFV600E gene mutation is found in about 66 percent of melanomas; particularly those arising in younger patients. This BRAF mutation activates certain enzyme pathways that are involved in many cell processes. Studies have identified this non-inherited mutation in the BRAF gene that appears to be the most common event in the process that leads to melanoma.
The V60L mutation is more common in people with light hair and skin tone that, despite being light, tans easily in the summer. This mutation is positive for the climate of the Mediterranean region, as it facilitates the absorption of vitamin D in the winter months, in which the ultraviolet radiation is lower. In the summer months, in which the radiation is greater, the ease to darken the skin pigmentation provides a certain protection. However, a study revealed that among people with this mutation, there is a greater predisposition to skin cancer.
Increasing evidence has shown that the greater the number of variations of gene MC1R (melanocortin-1 receptor), the greater the risk for inherited melanoma. The MC1R gene plays an important role in determining if a person has red hair, fair skin, and sensitivity to UV radiation, it also regulates the synthesis of melanin. MC1R is more common in Northern European countries posing a greater risk of skin cancer to those who have high exposure to ultraviolet rays. People who have olive and darker skin and who carry one or more variations of this gene have a higher than average risk for melanoma. The MC1R gene, which being whiter – ‘fair skinned’ is also associated with an increased susceptibility to melanoma.
There are many factors beyond genetics that facilitates the synthesis of vitamin D which is key in the periods of gestation and growth, in a way that its proper absorption is critical to the survival of human beings. Other influences on the risk of developing skin cancer include an excessive exposure to ultraviolet rays.
Skin cells are always being overwhelmed with radiation and certain genes are responsible for fixing the damage. When a gene called ‘patched 1’ (also known as PTCH1) is inactivated it causes an increase in excessive cell growth, also known as cancer. Patched 1 was found in a fruit fly called Drosophila melanogaster and is located on the ninth chromosome in humans. Malfunctioning patched 1 leads to defective embryonic development and many types of skin cancer. Patched 1 is usually born in a somatic cell so inheritance of a mutated version is rare. When it is inherited, the embryo usually cannot survive, since apoptosis (controlled cell death) is so important in embryo development. Patched 1 is also responsible for apoptosis. When this gene does not work tissue structure is not maintained, embryo's toes and fingers do not take shape, and skin cancer can grow unchecked. Hedgehog, the gene that turns on the patched 1 gene, can also lead to skin cancer when it does not function. The gene product of hedgehog is a protein that rests on the cell membrane and sends signals to the nucleus of the cell. The hedgehog protein determines cell growth and other things too. It starts different genes all at the same time, even the patched 1 gene.
P53 is another gene that plays an important role in the cell cycle, and cancer can form when it doesn’t function. If one of the two genes, patched 1 or P53, is inherited in a mutated way that affects its function, the chances for getting skin cancer is great. Those inheriting the mutated form of P53 have a 50% chance of chance of getting cancer by age 30 and a 90% chance by the time they are 70. Skin cancer in people who have the gene is very common because skin cells are in a constant state of repair. When the cells cannot see their DNA damage, they will divide no matter what is wrong with them. Both patched 1 and P53 are germ-line gene mutations.
People have different skin colors mainly because their melanocytes produce different amount and kinds of melanin. The genetic mechanism behind human skin color is mainly regulated by the enzyme tyrosine, which creates the color of the skin, eyes, and hair shades. Differences in skin color are also attributed to differences in size and distribution of melanosomes in the skin. Melanocytes produce two types of melanin. The most common form of biological melanin is eumelanin, a brown-black polymer of dihydroxyindole carboxylic acids, and their reduced forms. Most are derived from the amino acid tyrosine. Eumelanin is found in hair, areola, and skin, and the hair colors grey, black, yellow, and brown. In humans, it is more abundant in people with dark skin. Pheomelanin, a pink to red hue is found in particularly large quantities in red hair, the lips, nipples, glans of the penis, and vagina.
As a general rule, to spot either melanomas or non-melanoma skin cancers – such as basal cell carcinoma and squamous cell carcinoma, take note of any new moles or growths and any existing growths that begin to grow or change significantly in any other way. Lesions that change, itch, bleed, or don’t heal are also reason to be concerned.
A – Asymmetry if you draw a line through this mole, the two halves will not match.
B – Border- the borders of an early melanoma tend to be uneven. The edges may be scalloped or notched.
C – Color- having a variety of colors is another warning signal. A number of different shades of brown, tan, or black could appear. A melanoma may also become red, blue, or some other color. D – Diameter- Melanomas are usually larger in diameter than the size of the eraser on your pencil (6mm) but they may sometimes be smaller when first detected.
E – Evolving Any change – in size, shape, color, elevation, or another trait, or any new symptom such as bleeding, itching, or crusting – points to danger.
In conclusion, when it comes to spots on the skin, it is always better to be safe than sorry. The incidence of melanoma at a global level is increasing faster than the other types of cancer with approximate doubling rates of 10 to 20 years in countries with fair-skinned populations. Melanoma is the second most common cancer in the age group of 15 to 34. Melanoma is curable when detected in the early stages with surgery being the most common treatment for early stage melanoma. As for what is in the future for melanoma, research is headed in three directions: 1.) Prevention – public education and more widely available screening clinics to increase public awareness of the need for sun avoidance, sunscreen use, and the early detection of suspicious spots. 2.) More Precise Diagnosis – newer experimental techniques may help doctors make more certain calls on borderline or suspicious spots. 3.) Better Treatment for Advanced Disease – Due to the fact that conventional chemotherapy has been disappointing with melanoma, researchers have turned their attention to biologic treatments of advanced melanoma to stimulate the body’s own immune response against the tumor. These biologic treatments include interferon, interleukins, monoclonal antibodies, and tumor vaccines.

References
Alonso S, Boyano D, de la Rúa C, del Mar Pino-Yanes M, Flores C, García O, García de Galdeano A, Gardeazabal J, Ibarrola-Villaba M, Izagirre N, López S, Martínez-Cadenas C, Ribas G, Sevilla A, Smith-Zubiaga I. Simultaneous purifying selection on the ancestral MC1R allele and positive selection on the melanoma-risk allele V60L in south Europeans. Mol Biol Evol: 2654-65. doi: 10.1093/molbev/mst158. Epub 2013 Sep 17. http://www.ncbi.nlm.nih.gov/pubmed/24045876
ASCO Annual Meeting (Ed.). Combination of Two Targeted Therapies Slows Advanced Melanoma Growth with Fewer Side Effects. From http://www.cancer.net/ combination-two-targeted-therapies-slows-advanced-melanoma-growth-fewer-side-effects
Caspermeyer, J. (2013). Evolutionary Medicine of Skin Cancer Risk among Europeans (S. Kumar, Ed.). Molecular Biology and Evolution, 30(12), 2736-2736. doi:10.1093/molbev/mst181, from http://mbe.oxfordjournals.org/content/early
Dermatology Department, Norfolk and Norwich University Hospital, Norwich, UK. (2009). Melanoma epidemic: A midsummer night's dream? The British Journal of Dermatology, 161(3), 630-4. doi: 10.1111/j.1365-2133.2009.09299
Oxford University Press. (2013). Mutation V60 increases predisposition to skin cancer. Molecular Biology and Evolution, 30(12). Retrieved from http://mbe.oxfordjournals.org
Parry, C. (2008). L’Oreal aims for children with Ambre Solaire sun protection awareness campaign. Retrieved from Marketing Week: http://www.marketingweek.co.uk/news/loreal-aims-for-children-with-ambre-solaire-sun-protection-awareness-campaign/2060694.article