3.2 Review MI

In what ways do different risk factors increase the chance that a person will develop cancer? How can lifestyle changes reduce the risk for developing cancer?

Biological Age – the risk for all cancers increase Infections – Some viral and bacterial infections can cause an increase risk of cancer Reduce these risks by being screened often and getting vaccinations Genetic Sometimes a gene can be inherited from parents that increases the risk of cancer, because you already one step (mutation) towards cancer. Hereditary cancer and familial cancer would be genetic. Sporadic cancer (most cancers) are not genetic.

Environmental Pollution – Smoke and chemicals, like asbestos, can damage DNA UV Radiation - More on this later Radiation – Excessive radiation from sources, like Xrays Behavioral Red meat and other foods have been shown to increase risks of cancer (other foods, like antioxidants have been shown to lower cancer) Smoking increases risk of lung cancer (same with smokeless tobacco and mouth cancer) Not taking preventative measures, like staying out of the sun

Skin Cancer Types Basal/Squamous – most common and least dangerous form that can be found anywhere on the body Melonoma – most common on face, chest, and legs, and are more likely to metastize ABCDE Asymmetry Border irregularity Color changes Diameter greater than 1/4 inch (about 6 mm) Evolving

Skin Cancer Treatment pyrimidine antagonists – inhibit the enzyme that makes pyrimidines (thymine, uracil, cytosine), which stops the production of DNA and RNA. While this works in some patients it has a variety of side effects including burning and sun senstivity when using it on skin

How can molecular tests be used to detect inherited genetic mutations associated with certain cancers?

Genetic Marker Analysis – Easier and cheaper genetic analysis than DNA Sequencing. These are located directly in front of the gene in question (therefore, often passed on with the gene) Markers are Short Tandem Repeats (non-coding DNA that are repetitive sequences of DNA) STRs are highly variable by length (sequence can repeat any number of times making them different lengths) Easy to identify STRs using gel electrophoresis because they are simply different lengths

How can molecular tests be used to detect inherited genetic mutations associated with certain cancers?

Use of genetic markers Use them in conjunction with pedigrees 1.Identify people with gene for cancer 2.Conduct a marker analysis on family members and unknown family member using gel electrophoresis 3.Identify STR sizes using standard curve 4.Compare STRs and identify alleles possessed by each family member 5.Analyze allele to see if there is a correlation between alleles and family members with cancer

Breast Cancer Genetic Component BRCA 1 and BRCA 2 are tumor suppressor genes Mutations in these may lead to tumors 5-10% of breast cancers are related to these genes BRCA 2 genes are linked to male breast cancer Preventative measures Prophylactic mastectomy – reduces risk of breast cancer by 90% Get it test positive for BRCA 1 or 2 genes, calcium deposits, radiation therapy, or previous breast cancer Hormonal therapy – medicines or removal of the ovaries in order to reduce estrogen Nutrition Physical Activity

How can viruses lead to cancer?

Viruses can cause cancer by injecting DNA into cells and thereby causing a mutation HPV – linked strongly to cervical cancer, vaccines may help, but will not guard against every strain EBV – may lead to lymphomas Hepatitis B - Vaccine Hepatitis C – No vaccine both may lead to liver cancer

What is the importance of routine cancer screenings?

You should get routine screenings for: Prostate Colon Cervical Breast Skin Testicular lung Early detection of cancers is crucial to stop the metastases process before the cancer spreads and cause problems elsewhere. It is also easier to treat and cure cancer when caught early