Cancer Booklet Flashcards
The production of cyclins at each stage of the cell cycle is stimulated by ____ and inhibited by ____
Positive growth signals
Negative growth signals
Cancer cells have six distinct features, which are
- growth without “go” positive signals
- Failure to respond to “stop” (negative) signals
- Evasion of programmed cell death
- Unlimited cell division
- angiogenesis
- tissue invasion and metastasis
Growth factors are
proteins found in the body that attach to cell surface receptors and allow the m to divide
TorF: cancer cells can divide without having growth factors present
true
How are cancer cells able to divide without having growth factors present?
mutations in oncogenes
What is contact inhibition?
When normal cells are in contact with each other and there is no space between them, they do not divide
p53, when functioning normally, acts as
a tumor suppresor. When DNA is damanged, p53 halts the cell cycle by blocking cyclin activity in G1 to repair damage
can also trigger apoptosis
Both the loss of cell cycle growth control or the loss of death signals can result in
unregulated cell growth
Normal cells can divide approximately ___ times
60
Do telomeres code for proteins?
no, thats why losing some of these sequences throughout the lifetime
The two most critical angiogenic proteins are
VEGF and bFGF
How are cancerous cells capable of crawling?
rearranging their cytoskeleton to send out projections called filopodia
The three steps to tumor formation are
- initiation: first mutation
- promotion: mutation of the second copy of the same gene
- progression: multiple mutations accumulate
How does radiation promote cancer?
triggers production of free radicals
radicals can cause structural damage to both DNA and proteins
Viruses that have been associated with causing cancer are called
oncoviruses
