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
The Epstein-Barr Virus, or EBV, causes
mononucleosis and increases risk of lymphome
HPV has been associated iwth what cancer?
cervical cancer
The increased expression of P-glycoprotein is an example of… and results in
example of a mutation that can confer resistance to drugs
P is a transmembrane protein that functions as a pump that ejects cancer drugs from the cell before it can have therapeutic effects
The anti-apoptopic character of cancer is an ____ feature and is dangerous because
drug resistance feature
chemo agents use the strategy of damaging DNA and rely on DNA damage detective cells to trigger apoptosis, but cancer cells don’t really trigger apoptosis
How does cachexia arise?
metabolism of healthy cells is affected by signals released by cancer cells
Most cancer cells are aneuploidic, meaning
they have an incorrect number of chromosomes
Cancer stem cells, or CSCs could arise when
adult stem cells become mutated and experience excessive growth
cytotoxic T lymphocytes destroy cancer cells by
recognizing abnormal proteins on the surface of cancer cells and destroy them
Antibodies aid in destroying cancer cells by
binding to foreign proteins on the surface and tagging them for destruction
define DNA methylation
the addition of a methyl group to a DNA sequence. It is impossible to make proteins from a methylated DNA sequence
microRNA have been shown to ___ mRNA. This relates to cancer cells because
bloxk mRNA
cancer cells have aberrant levels of miRNAs, can incorrectly turn of needed genes
What are tumor markers?
proteins that are found in elevated levels in certain cancers
Define the three numbers for cancer staging (T, N, M)
T: 1-4 identify size of tumor and if its in one tissue
N: 0-2 identify presence of tumor cells in lymph nodes
M: 1 indicates metastases
