Microbio 160 Study Guide for Exam 2 Will cover lectures 11 22 a little from 24 and the guest lecturer from 11 6 Review notes from lectures as well as this study guide Textbook passages referenced in lecture slides Pay close attention to them Study the information on genetics dominant vs recessive Information on how having an inherited mutation can make it easier to have cancer How loss of function in tumor suppressor genes and protoncogenes The information on the pedigree on Xeroderma Pigmentosum Information on pedigree of retinoblastoma How inherited mutations for cancer are passed on Effect of birth year on breast cancer risk from BRCA mutations There is a correlation between skin cancer and sunlight exposure The progression of skin cancer as cells start to become mutated Incidence and Mortality rates for different types of skin cancer The effect of body weight on cancer risks How veggies can help prevent cancer How free radicals and antioxidants operate Know what Prognosis Means The course that a disease will most likely take What is the nature of cancer in terms of the diversity of mutations in cancer cells and tumors How do these mutations accumulate After a cell acquires a series of mutations and eventually they will start to proliferate and divide uncontrollably They can accumulate from a series of environmental factors or genetic factors There are some specific genes that when mutated are associated with cancer cells Be familiar with them and why they are linked to uncontrolled growth or increased rates of mutations p53 RB K ras BRCA 1 and BRCA 2 HER2 and APC APC and P53 are tumor suppressor genes so when they are mutated the cell is able to divide without stopping APC specifically when mutated can lead to colon cancer HER2 helps mediate normal cell growth and division and over expression of this gene can cause uncontrolled cell division and aggressive tumor growth breast cancer BRCA1 and BRCA2 are DNA repair genes and they can be inherited When they are inherited it is easier to develop a tumor breast cancer K ras is an oncogene that when mutated can increase cell proliferation When RB is mutated it makes a green light for the cell cycle so the cell can pass quickly through the cell cycle and divide Heredity and Cancer What is it that a person inherits in case of hereditary cancer Think about this in terms of genes and risks Family history can indicate a genetic predisposition to a hereditary risk for cancer A person inherits a mutation in a gene that can put them at a higher risk for a specific type of cancer What is the nature of an inherited mutation What types of mutated genes are associated with inherited risks There are various forms an inherited mutation can have A person can have a dominant trait for a mutation or a recessive trait for a mutation cell proliferation rate Mutated oncogenes into protoncogenes are associated with cancer will increase Tumor suppressor if mutated will speed up cell division Where and when do the mutations arise in the body when an inherited risk exists versus when there is no inherited risk When there is an inherited risk they develop in the germ cells sperm and egg cells and this happens before conception Non inherited risks are called somatic mutations and they happen after conception These happen in somatic cells which are any cells other than germ cells How does someone know if they might be at risk for an inherited gene associated with cancer They have a long family history of a specific type of cancer and they have family members who succumb to cancer early in life or at a very specific time in their lives Smoking and Lung Cancer Lung cancer is a deadly but preventable disease Why Yes lung cancer is an incredibly deadly and common disease It s preventable because most often lung cancer is due to cigarette use Thus making it highly preventable disease What is it about tobacco is a lethal cocktail of carcinogens How does Benzopyrene diol epoxide cause cancer Be specific What genes are often mutated in lung cancer There are more than 7 000 chemicals in tobacco smoke and 70 known to cause cancer carcinogens Benzopyrene is converted to an epoxide which will react with the guanine G on a DNA strand If not corrected it can cause the G to be read as a T and ultimately it can be read as a A T pair K ras and P53 genes are often found with this mutation or transversion in smokers K ras and p53 are often mutated Lung Cancer is the most fatal cancer What are the two main types of cancer and how do they differ Non small cell carcinoma and small cell carcinoma Non small cell develops in the outer boundaries of the lungs most commonly found in women and is 40 of all lung cancers Two types of non small cell lung cancer squamous cell carcinoma and large cell carcinoma Small cell creates it s own hormones which alter body chemistry Smoking tobacco is the major risk factor for developing small cell lung cancer Small cell without treatment is the most aggressive of any type of tumor Colorectal Cancers Colorectal cancer is one of the deadly but preventable diseases why Screening makes all the difference when trying to detect colorectal cancer It is most often linked to diet so eating healthy makes all the difference And it is a very common disease and often presents itself in people Colorectal cancer is interesting due to the predictability from polyp to the development of cancer Describe this progression and underlying biology There is a mutation in the APC tumor suppressor gene that causes the development of a polyp which is a benign growth There is a mutation with the RAS oncogene making it a protooncogene so there is an increase in cell proliferation making the growth bigger Malignant cells will start to appear at some point in the growth and this is caused due to a mutation in the tumor suppressor gene causing more uncontrolled cell division If the polyp is not removed some of the malignant cells will start to metastasize through the body Screening for colorectal cancer at the appropriate age can decrease mortality rates associated with this disease What are the appropriate screening protocols reviewed in class There should be fecal occult blood testing annually There should be a flexible sigmoidoscopy every five years Double contrast barium enema every 5 to 10 years Colonoscopy every 10 years Childhood Cancers What are the most common childhood cancers What differentiates childhood cancers from adult cancers Difference Cancer in adults is very
View Full Document
Unlocking...