Medical Interventions 3.2

• The different classes of risk factors are biological risk factors, behavioral risk factors, environmental risk factors and genetic risk factors
• Behavioral risks are risks that you can change, such as smoking, drinking, and eating unhealthy foods
• Environmental risk factors are toxins found in your surrounding environment that can increase your risk for cancer, such as radon, air pollution, second hand smoke and asbestos
• Biological risk factors are physical characteristics, such as gender, race, and age
• Genetic risk factors relate to genes inherited by your parents
• All risk factors alter DNA in our cells which will then potentially lead to cancer.
• Skin cancer is caused by exposure to UV photons that damage the DNA in our cells
• UV rays have mutagenic properties, meaning they are capable of causing mutations in DNA the more cells are exposed to it
• Types of skin cancer are basal/squamous cancer and melanoma
• Basal and squamous are the most common kind of skin cancer and least dangerous form that can be found anywhere on the body
• Melanoma is most common on the face, chest, and legs and are more likely to metastasize
• Skin cancer is the most common type of cancer in the US
• ABCDE guide for checking for melanoma: asymmetry, border irregularity, color (unusual), diameter above 6 millimeters, and evolution or change of the mole over time
• A cancer screening is a test that is performed to check for the presence of cancer
• Cancer screenings for females involve pap smears and mammograms
• Cancer screenings for males involve prostate exams
• When something disrupts the cell cycle without apoptosis, it is called a mutation and can cause cancer
• Three types of genes that are involved with cancer are proto-oncogenes, tumour suppressor genes and oncogenes
• A tumor suppressor gene is a gene that works inside cells to stop the growth and division of abnormal (tumor causing) cells
• Proto-oncogenes are a group of genes that cause normal cells to become cancerous when they are mutated
• The mutated version of a proto-oncogene is called an oncogene
• Proto-oncogenes encode proteins that function to stimulate cell division, inhibit cell differentiation, and halt cell death
• Oncogenes typically exhibit increased production of the proteins proto-oncogenes produce, drastically increasing the effects of the proto-oncogene
• Proto-oncogenes are suppressed by tumor suppressor, but once proto-oncogenes are mutated, they can cause uncontrolled cell growth and cancer
• In breast cancer, BRCA1 and BRCA2 are genes in breast cells that act as proto-oncogenes
• Mutations in BRCA1 and BRCA2 increase the risk of developing breast cancer by up to 80%
• BRCA1 and BRCA2 normally prevent DNA damage from occurring or repairing it if it does occur
• If either BRCA1 or BRCA2 becomes mutated, then the gene no longer functions properly and cannot stop the cell from growing abnormally
• Viruses can cause cancer by injecting DNA into cells and thereby causing a mutation
• More than 80% of cervical cancer are cause by HPV
• Virologists can identify cancer causing viruses and work towards developing vaccinations that will reduce those infections
• BRCA1 and BRCA2 are commonly mutated in people who develop hereditary cancer
• STR stands for short tandem repeats
• Marker analysis is a technique where the gene mutation is analyzed using a genetic marker instead of directly analyzing the gene itself
• An STR is a region of DNA composed of a short sequence of nucleotides repeated many times
• Genomics is a branch of biology that studies the entire genome of an organism.
• Different types of genes that aid cancer are oncogenes, tumor suppressor genes and DNA repair genes.
• Oncogenes are normal cellular genes that have been altered by mutations or other changes to become overactive and promote uncontrolled growth.
• Tumour suppressor genes normally prevent cells from growing out of control but when they don't work properly can lead to cancer.
• DNA repair genes play a role in detecting and correcting errors during DNA replication and preventing damage caused by environmental factors such as UV radiation and chemicals.