cancer

Question 1

what is cancer and what is a term for it

Answer 1

abnormal growth of bodies own cells
neoplasm

Question 2

what is a tumor and what are the two categories they are commonly sorted into

Answer 2

a tumor is localised swelling
the can be sorted into:
benign malignant

Question 3

what are some features of benign tumors

Answer 3

rarely life-threatening
do not invade neighboring tissue
do not metastasize

Question 4

what are some features of malignant tumours

Answer 4

maybe life threatening
can invade and destroy nearby tissues
can metastasise

Question 5

how do cancers metastasise

Answer 5

cancer cells can invade neighbouring tissues, and if those tissues have a blood supply then cells can break away from the tumour and reattach to a different part of the body
these are called secondary tumours

Question 6

what is an example of a cancer that speads readily and one that barely spreads

Answer 6

melanoma spreads early
glioma barely spreads at all

Question 7

whats are the primary naming conventions of cancer

Answer 7

most cancers are named for the tissue they originate from
some are named after their discoverer

Question 8

what are the two major cancers for men and women and what are the cancers asossiated with both groups

Answer 8

prostate(25%), breast(31%)
lung bowel and skin(~10-15%)

Question 9

what is the age distribution of cancers

Answer 9

two thirds of cancer are over 65s
one third is over 75s

Question 10

how does cancer proliferate relative to other cells

Answer 10

cancer outcompetes other cells which in large eukaryotic organism is hamrful

Question 11

what are the exogenous factors that contribute to cancer formation

Answer 11

smoking
diet
sunlight
occupation
viruses such as hpv, ebv
genetic mutation (inherited)
hormone such as glorious glorious estrogen

Question 12

what are carcinogens and mutagens

Answer 12

carcinogens are substances or radiation that directly cause cancer
mutagens react with dna

Question 13

what are the two categories of genetic changes that give rise to cancer

Answer 13

proto-oncogenes to oncogenes and inactivation of tumour suppressor genes

Question 14

where in the body are mutations in cells the most dangerous

Answer 14

is most dangerous in stem cells as they are long lived

Question 15

what is the car metaphor for cancewr genes

Answer 15

oncogenes drive cancer when activated too much
like a car accelerator

tumour suppressor genes cause cancer when they are turned off or lost (brakes)

Question 16

what typifies an oncogene from a protooncogene

Answer 16

an oncogene is either active too much or active at inappropriate times
some control cell proliferation

Question 17

what are the types of mutation that give rise to cancer and what do they do

Answer 17

point mutation: can create a hyperactive or resistant to degradation

Gene amplification: causes growth-stimulating hormone/ protein to be produced in excess

transposition: leads to a new promoter that might overproduce

Question 18

what are the most specific common mutations in cancer genes

Answer 18

p53 and pik3ca

Question 19

what is pik3ca

Answer 19

is a lipid kinase which phosphorylates a lipid to make a growth factor

Question 20

what is p53

Answer 20

a transcription factor that causes cells to stop growing and die under cellular stress and damage

Question 21

does pi3k mutation increase or decrease the enzyme activity

Answer 21

generally increase in problematic mutations

Question 22

what can overexpression and amplification do to certain genes and what are some examples

Answer 22

MYC in luekemia and lung cancers
EGFR in cancers such as lung and colon
her2 in breast cancer

Question 23

what is her2, what cancer does it cause in what percentage

Answer 23

her2 is a gene amplification cancer, it forms breast cancer, and is responsible for about 20% of cases

Question 24

what is translocation chromosomal mutation

Answer 24

where translocation brings two previous sections of a genome together, its a large scale genomic rearrangement

Question 25

what are generally the two changes that result in cancer during chromosomal mutation

Answer 25

synthesis of a new fusion protein
inappropriate expression of protein

Question 26

what causes almost all chronic myloid leukaemia

Answer 26

almost all cml cases are caused by a translocation of bcr onto able protein, causing a unregulated protein tyrosine kinase

Question 27

what do tumour suppressor genes do in normal cell function

Answer 27

code for protiens for which the normal function makes cancer less likely
if those cells mutate or inactivate, those cells progress to cancer, usually in combination with other cells

Question 28

what is p53 and why is it called that

Answer 28

named cause the protein has a mass of 53kda
when properly functioning, it binds to promoter sites to prevent transcription

Question 29

what other things to the tp53 genes do

Answer 29

it can detect dna damage and prevent the progression of the cell through the replication checkpoint
if the damage is minor, replication is halted till repair, if not the apoptosis of the cell is triggered
50% of cancer has a tp53 mutation

Question 30

how often do mutations happen

Answer 30

slightly less than one every division

Question 31

what catagories can mutations be split into, relating to their role in driving cancer

Answer 31

driver mutations which cause cancer
passenger mutations are common but do not drive cancer