6 hallmarks Flashcards
Hallmark 1
self-sufficient growth signals
cells and proliferate on their own without signals from something else
EX: RTK signal transduction pathway where RAS is constitutively on.
Thyroid cancer
MAPK - mitogenic cell proliferation
PI3K - anti -apoptosis
Hallmark 2
resistance to inhibitory signals
cancer due loss of expression to inhibitory growth signals
PI3K is anti apoptotic and PTEN can reverse it
NF1 can inhibit RAS
Hallmark 3
evade apoptosis
disruption of apoptosis pathway to prevent DNA damage or cell cycle checkpoint. P21 is cell cycle checkpoint. loss of P53 function or BAX function can resist apoptosis.
Hallmark 4
limitless potential
cells normally only divide 60-70 times. Due to telomeres that shrink every time cells replicate. Telomerase can stimulate growth of telomeres that can cause immortalization and continued proliferation
Hallmark 5
tumor cells trigger angiogenesis
tumor cells require oxygen and vascularization to grow. They stimulate VEGF that is responsible for angiogenesis.
Hallmark 6
invade tissues and metastasizes in distant locations
metastatic tissue invades basement membrane and enters ECM. Then the tissue finds its way into vascular system. Travels down vascular system and metastasizes downstream