Cancer Cell Death Flashcards
Where are the cell cycle checkpoints?
> After G1 (before S phase)
During S phase
During G2
During mitosis (spindle assembly checkpoint)
What is cornification?
Caspase-4 activation
What is intrinsic apoptosis?
Mitochondria and cascade associated apoptosis
What is extrinsic apoptosis?
Apoptosis that occurs via: death receptors (involving caspase 3 and 8 activation) or dependence receptor activation
What is anoikis?
This is a form of caspase-dependent cell death that is induced by anchorage-dependent cells; detaching from the surrounding extracellular matrix.
What is pyroptosis?
This is involved with antimicrobial responses during inflammation and requires the function of caspase 1
What is entosis?
Where a cell dies as a result of becoming engulfed by a neighbouring cell
What are the main differences between caspase-dependent and caspase-independent apoptosis?
Caspase-dependent apoptosis can be stopped by a caspase inhibitor, involves nuclear fragmentation, small scale DNA fragmentation and DNA ladders.
Caspase-independent apoptosis can’t be inhibited in this way, there is no nuclear fragmentation, there is large scale DNA fragmentation and no DNA ladders.
What are the forms of caspase-dependent cell death?
Anoikis, intrinsic apoptosis, extrinsic apoptosis (by death receptor and dependent receptors) and pyroptosis
What are the forms of caspase-independent apoptosis?
Autophagy, caspase-independent intrinsic apoptosis, enosis, necroptosis, neurosis and parthanatos
What is necroptosis?
Death receptor mediated cell death without caspase activation
What is immunogenic cell death?
A cell death modality that stimulates an immune response against dead-cell antigens, in particular when they derive from cancer cells.
What are the causes of apoptosis?
> Physiological activators - TNF, TGF etc.
Damage-related inducers such as heat shock, viral infection and free radicals
Therapy associated agents such as chemotherapy drugs
Toxins such as ethanol or beta-amyloid plaque
What are the morphological features of apoptotic cells?
> Cellular and nuclear condensation
Nuclear fragmentation
Nuclear and mitochondrial condensation
Cellular fragmentation
What are the biochemical features of apoptotic cells?
> DNA fragmentation
DNA fragments accumulate in the sub-G0/G1 phase
Phosphatidyl serine exposure (eat me signal)
