x-ray
Electromagnetic radiation sends individual photons through body shows dense structures (bone) 2d image examines bones, teeth, lungs, breast, heart, blood vessels, digestive tract
CT scan
a series of x-ray photographs taken from different angles combined by computer into a composite representation of a slice through the body computerized axial tomography examine chest, abdomen, pelvis, spine, other skeletal structures
MRI
uses powerful magnets and radio waves scans the body by turning small magnets off and on produces detailed images of soft tissues cross-sectional images of body examine brain, spine, joint, abdomen, blood vessels, and pelvis
bone scan
nuclear medicine scan using radioactive dye to visualize bones machine passes gamma camera over body to record tracer pattern in bones 2d images finds abnormal bone metabolism
Proto-oncogenes
the corresponding normal cellular genes that are responsible for normal cell growth and division
oncongenes
gene in which certain conditions can transform a cell into a tumor cell
tumor suppressor genes
make proteins that stop cell division and kill cells regulates cell division
mutated tumor suppressor genes
the protein it encodes is not produced or does not function properly, and as a result, uncontrolled cell division may occur
DNA repair genes
a collection of processes by which a cell identifies and corrects damage to the DNA molecules that encode its genome
mutated DNA repair genes
increase genomic instability and mutation
normal cells
-replicate in an organized manner -die after a limited number of cell divisions -distinct features that enable them to perform their specific function -same size and shape -one small nucleus with common shape -arrange themselves in an organized manner -well-defined tissue boundaries
cancerous cells
-can replicate indefinitely -lose specialized features, cannot perform proper functions -vary in size + shape -large, variably shaped nuclei, often multiple nuclei -disorganized arrangement, no clear borders
Levels of Abnormality
normal, hyperplasia, mild dysplasia, carcinoma in situ, cancer
hyperplasia
contains a higher than usual number of cells cell structure and orderly arrangement of cells are what is seen in healthy tissue cells
mild dysplasia
The tissue shows loss of standard tissue arrangement and cell structure, which is not extreme, thus is not considered cancerous.
carcinoma in situ
shows uncontrolled growth of cells and aberrant tissue arrangement and cell structure changes remain within original location
cancer
shows uncontrolled growth of cells and aberrant tissue arrangement and cell structure migrate beyond the original location
upregulation
more mRNA is produced in gene than normal
down regulation
less mRNA is produced in gene than normal
Isolate mRNA from cells of interest
step 1 of DNA microarray these cells will be from healthy and cancerous tissue
create cDNA
step 2 of DNA microarray an enzyme transcribes the mRNA and DNA to create complimentary DNA
label cDNA to be visualized in the microarray
step 3 of DNA microarray helps identify regulation of genes
Hybridization
step 4 of DNA microarray as the cDNA washed over the chip it will hybridize (bind) to any well that has its complimentary strand
analyze the microarray
step 5 of DNA microarray results
combined cDNA images
step 6 of DNA microarray to show what genes need to be monitored where genes are not regulated, normal, increased, decreased, or not expressed
green color in microarray
healthy cell
red color in microarray
cancer cell
yellow color in microarray
mRNA expressed equally in both cells
white color in microarray
no mRNA expressed in either cell
Human carcinoembryonic antigen (CEACAM6)
This gene codes for a protein that is located in the extracellular matrix. This protein is involved with adhesion between cells and is thought to be a proto-oncogene and when over-expressed is an oncogene. (increased)
Surfactant protein B (SFTPB)
This gene codes for proteins that assist breathing and is not involved in the regulation of the cell cycle. (normal)
p53 tumor suppressor (TP53)
This gene codes for a protein that is located in the mitochondria and in the nucleolus. This protein is involved with cell cycle checkpoints. This gene is a tumor suppressor gene and is thought to be the "Guardian of the Genome." (decreased)
SRY
This gene codes for a protein that is located in the nucleus. The protein that this gene codes for is testis-determining factor (TDF) which initiates male sex determination. This protein has no function in lung cells. (no expression)
Cytochrome P450 (CYP1A1)
This gene codes for a protein that is located in the endoplasmic reticulum. The protein catalyzes reactions involved in drug metabolism and synthesizes cholesterol, steroids, and other lipids. The expression of this protein is induced by some polycyclic aromatic hydrocarbons (PAHs), some of which are found in cigarette smoke. (increased)