Neoplasia (M) Flashcards
What is the nationality and profession of Willis?
He is a British oncologist
As defined by Willis, what is neoplasia?
It is an abnormal mass of tissue the growth of w/c exceeds and is uncoordinated w/ that of normal tissue and persists in the same excessive manner after cessation of stimuli w/c evoked the change
What are the phases of cell cycle?
1) G0
2) G1 - presynthetic
3) S - synthetic
4) G2 - premitotic
5) M - mitotic
What are the grps of cells accdg to proliferative potentials?
1) Labile cells
2) Stable cells
3) Permanent cells
What are labile cells?
These are cells that are continuously dividing
What are stable cells?
These are also called as quiescent cells
What are permanent cells?
These are nondividing cells
Cell proliferation can be stimulated by what?
1) Injury
2) Cell death
3) Mechanical deformation of tissues
How can growth be accomplished?
It can be accomplished by shortening the cell cycle
What are the most impt factors in relation to growth?
Those that recruit resting or quiescent cells into the cycle
What are the fxns of molecular controls and what is its result?
Regulate and orchestrate events leading to cell division
What is involved in cascade of protein phosphorylation?
Cyclins
What are the fxns of set of checkpoints (present in the cell cycle)?
1) These monitor molecular events
2) These may delay the progression to the next phase of the cell cycle
What are the fxns of checkpoints?
1) These provides surveillance mechanisms
2) These causes cell cycle arrests
What is the purpose of providing surveillance mechanisms done by checkpoints?
For ensuring that critical transitions occur in the correct order w/ fidelity in their completion
How does checkpoints cause cell cycle arrests?
By promoting inhibitory pathways or inhibiting activation pathways
Why is p53 activated and what is its result?
In response to DNA damage w/c in turn activates p21
*What is p21?
It is a CDK inhibitor
What is the fxn of CDK1B complex?
It controls transition from G2 - M
*The fxn of CDK1B complex is done after what?
After completion degraded by ubiquitin-proteosome pathway
What is the action of CDK1B complex?
It may bind w/ CDK inhibitors
What is the definition of new growth?
Neoplasm
What is the definition of “onco”?
Tumor
What is cancer?
It is a malignant neoplasm