1 What is Cancer?

Question 1

What is cancer?

Answer 1

uncontrolled growth of abnormal cells in a tissue, invasive and spreading

Question 2

What are the 6 hallmarks of cancer?

Answer 2

gaining independence from external signals

circumventing the regulation of cell proliferation

evading apoptosis

gene mutation causes cell death and supports uncontrolled proliferation

formation of tumour associated vasculature is a critical rate determining step

activating tissue invasion and metastasis

Question 3

Where are sarcomas normally found?

Answer 3

mesenchymal cells

Question 4

What is the effect microevolution?

Answer 4

an accumulation of 5-10 critical mutations over may years

Question 5

Genes controlling what processes may cause cancer?

Answer 5

growth
receptors
apoptosis
cell cycle
stemness
DNA repair

Question 6

What are the 3 key steps to cancer development?

Answer 6

initiation
clonal expansion
introduction to foreign microenvironments

Question 7

What role does the TsG play in cancer?

Answer 7

in normal function, it regulates cell growth

a protein from either allele is enough, so both alleles need to be lost to cause the suppressor effect

Question 8

What is the role of oncogenes in cancer?

Answer 8

positive regulator of cell growth - makes cells grow

even when only one allele is mutated

Question 9

what processes cause a cell to gain independence form external signals?

Answer 9

alterations of…

extracellular growth signals
transmembrane transucers of growth signals
intracellular circuits that translate those signals (Ras protein)

Question 10

How might extracellular growth signals be altered?

Answer 10

secretion of self-growth factors

Question 11

How might transmembrane transducers of growth signals be altered?

Answer 11

constitutive activation and over-expression of receptors

Question 12

What does the Ras protein do?

Answer 12

initiates 3 major downstream cascades

constitute a group of small regulatory GTPases functioning as molecular switches

HRas, KRas, NRas

Question 13

How might a cell circumvent the regulation of cell proliferation?

Answer 13

disruption of pRB (TSG) pathway

loss of control ovr progression from G1 to S phase

Question 14

What is the function of pRB?

Answer 14

guards the restriction point

Question 15

how might a cell evade apoptosis?

Answer 15

loss or mutation of p53

this might be because of DNA repair disruption, or disruptions to post-transnational modification processes

Question 16

How does p53 affect cheomtherapy responsivess?

Answer 16

loss of p53 reduces the responsivess to chemo

Question 17

What are the downstream effects of p53?

Answer 17

cell cycle arrest
DNA repair
block of angiogenesis
apoptosis

Question 18

How might telomere function affect cell death and proliferation?

Answer 18

normally, we have 6 base pair segments protecting the ends of chromosome, one is lost at each replication

cancer cells increase expression of telomerase (adds protective telomeres)

Question 19

how can cancer cells interact with the tumour environment?

Answer 19

changes in expression of adhesion receptors (caderhin, integrins)

activation of extracellular proteases

Question 20

The release of what from mitochondria leads to apoptosis?

Answer 20

cytochrome C

Question 21

What are the 8 stages to the metastsatic process?

Answer 21

primary tumour
vascularisation
detachment
intravasation
circulating tumour cell
adhesion to blood vessel wall
extravasation
growth of secondary tumour

Question 22

Name 4 sorta additional hallmarks to cancer

Answer 22

deregulating cellular energetics
avoiding imunne destruction
tumour-promoting inflammation
genome instability and mutation

Question 23

What will environments characterised by less disruption but limited resource availability select for?

Answer 23

slow life history hallmarks

Question 24

What are the 5 fast life history strategies?

Answer 24

evading growth suppresors
activating invasion and metastasis
sustaining proliferative signal
enabling replicating immortality
genome instability and mutation

Question 25

What are the 3 slow life history strategies?

Answer 25

inducing angiogenesis
evading immune destruction
resisting cell death