1. 3.1 REVIEW MI
Mr. Nuri/EAST Academy

2. WHAT FUNDAMENTAL CHARACTERISTICS DO ALL CANCERS HAVE IN COMMON?
Genetic component
Environmental component – Smoking, radiation, diet/health
If caught early and removed before it spreads the cancer may not cause problems
If it spreads/metastasizes there could be potential problems
Incidence of cancer increases with age
Cancer can affect any organ or tissue in the body

3. WHAT FUNDAMENTAL CHARACTERISTICS DO ALL CANCERS HAVE IN COMMON?
Proto-oncogenes – Normally control cell division by telling the cell to divide. Cancer can be caused by these genes being turned on too much
Mutation can cause them to be oncogenes, which lead to uncontrolled division
Translocation of a promoter can cause the oncogenes to be turned on more than they are supposed to be
A mutation can cause multiple proto-oncogenes, which will cause it to be overexpressed and uncontrolled cell division

4. WHAT FUNDAMENTAL CHARACTERISTICS DO ALL CANCERS HAVE IN COMMON?
Tumor-Suppressor Genes– Normally control cell division by telling the cell to stop dividing. Cancer can be caused by these genes being turned off
Example is the p53 gene
Triggers apoptosis (programmed cell death) if there is a mutation
Activates DNA repair enzymes to repair any mutations
Halts the cell cycle so no copies of the cell are made with the mutation
Mutations in these genes can lead to cancer

5. WHAT FUNDAMENTAL CHARACTERISTICS DO ALL CANCERS HAVE IN COMMON?
Cancer cells can proliferate indefinitely in culture.
Cancer cells do not exhibit contact inhibition. Once cancer cells cover the surface of the dish, the cells will continue dividing and pile up on top of each other.
Cancer cells undergo morphological changes and will exhibit various shapes.
Cancer cells can grow under less stringent conditions, and can usually grow on simple culture medium.
Cancer cells often have an abnormal number of chromosomes and the chromosomes often have an abnormal structure.

6. IN WHAT WAYS ARE DIAGNOSTIC IMAGING TECHNOLOGIES USED TO DIAGNOSE AND TREAT DISORDERS?
X-Ray – uses radiation to view broken bones bones, lung diseases, and digestive system
CT scan – uses multiple X-rays in a tube to produce cross-sectional views of bone and soft tissue, like organs.
MRI – uses magnets to produce detailed cross- sectional views of soft body tissue to identify diseases.
Bone Scan – Add radioactive tracers that are soaked up by the bone to produce full skeletal view to identify abnormal bone growth

7. WHAT DO DNA MICROARRAYS MEASURE?
DNA microarrays measure the number and amount of genes turned on and off in cancer cells vs. normal cells
We can do this by collecting mRNA from the cells, which will only be made if the genes are turned on
We can also determine if there is a correlation between genes interacting with each other

8. HOW IS DNA MICROARRAY TECHNOLOGY USED TO DETERMINE THE DIFFERENCES IN GENE EXPRESSION BETWEEN DIFFERENT TISSUE SAMPLES?
Red – The genes are only on in cancer cells
Yellow – The genes are on in cancer and normal cells
Black – The genes are not on in either cells
Green – The genes are only on in normal cells

9. HOW IS DNA MICROARRAY TECHNOLOGY USED TO DETERMINE THE DIFFERENCES IN GENE EXPRESSION BETWEEN DIFFERENT TISSUE SAMPLES?
Microarrays can also tell us the relative intensity of the gene expression because there will be varying shades of the colors.
The bright red would be a high expression of the gene in cancer cells, where as the dark red would be a low expression.
The same would be true for the yellow and the green

10. HOW IS DNA MICROARRAY TECHNOLOGY USED TO DETERMINE THE DIFFERENCES IN GENE EXPRESSION BETWEEN DIFFERENT TISSUE SAMPLES?
We can superimpose the colors from the cancer gene and the normal gene over each other to get one single color.
We assign this color a number (ratio)
A number over 1 the gene is expressed more in cancer cells
A number under 1 the gene is less expressed in cancer cells
A number equal to 1 the gene is expressed the same in both cells
0 means the gene is not expressed in either cell

11. HOW ARE THE SIMILARITIES OF GENE EXPRESSION PATTERNS BETWEEN DIFFERENT INDIVIDUALS CALCULATED?
Using statistical analyses we look at gene expression of several genes in several patients that have the same disease.
We use correlation coefficients to determine if there is a pattern between what genes are turned on and what genes are turned off
If there is a positive correlation then both of the genes are behaving in the same way
If there is a negative correlation then the genes are behaving in opposite ways (one is on and the other is off)
Correlation of 1 means that gene expression is identical
Correlation of 0 means there is no correlation
A number further from 0 and closer to 1 means that there is a stronger correlation