ONCOLOGY - review Flashcards
EXAM 2 content
what is a genome?
organism’s complete set of DNA
what is a neoplasm?
new growth, referred as a tumor can be BENIGN or MALIGNANT
what is a benign tumor?
abnormal cells that are localized & does not travel
what is caner?
abnormal cells divide without control & invades other tissues
what is a malignant tumor?
spreads to other areas of the body
what is the cell cycle? what are the stages of the cell cycle?
the growth stages of a cell going thru mitosis & regeneration
G0 = cell resting, not active or engaged in cell cycle
G1 = cell enters cycle –> grows –> preps for DNA replication
S = synthesis of DNA & each 46 chromosomes are duplicated
G2 = checking duplicated chromosomes for any errors or need repairs
M = mitosis
Cytokinesis = end of mitosis, official split, 23 pairs of chromosomes
what is so different with the cancer cell cycle? what is happening with the tumor?
- cells are actively dividing
- as tumor increases –> more cells into resting state G0 –> non cycling cells –> can escape death & stay into G0 phase
- major issue combating cancer!!
no check points, no resting, no control
in normal cell growth, what is proliferation?
cell growth = proliferation
- stem cells = undifferentiated cells
- cell proliferation starts IN stem cell
- mature cells comes out & functions until dies
how is proliferation activated? how does the body control it?
proliferation is activated by:
- cell degeneration / death
- body incr need for more cells (due to infection)
body controls it through:
- contact inhibition: respecting boundaries of cell around them
which parts of the body have rapid proliferation?
- bone marrow
- hair follicles
- epithelial line of GI tract
which parts of the body have slow proliferation or dont even occur?
myocardium & cartilage
what is normal cell differentiation? what is different between an immature & mature cell?
differentiation = immature cells –> mature form & function
- unspecialized –> specialized
- immature = potential to perform all body functions
- differentiate –> potential lowers
- mature = only specific functions, stable, will NOT go undifferent
what are the two main dysfunctions that happens in the body when cancer starts to arise? what happens within these dysfunctions?
defective cell proliferation
- loss of contact inhibition –> cancer cells grow on top of normal ones –> responds differently to intracellular (signals that regulate proliferation + death) + proliferate @ same rate as norm cells –> cancer cell proliferation is continuous & indiscriminate
defective cell differentiation
- can not preform special function
- cancer cells DEdifferentiate (return to previous state)
what are the stages of cancer development?
1st stage = tumor initiation
- spontaneous alternation / mutation of genes –> dysregulation of proliferation, apoptosis, & DNA repair
- exposure to carcinogenic agent
2nd stage = tumor promotion
- population of cancer grows
- diversity of cancer cell phenotypes
3rd stage = tumor progression
- metastasis = spread to adjacent & distal sites = final stage of neoplasm transformation
- tumor size grows
- proliferating cells do more mutations –> invasive & metastatic potential
when a tumor metastasizes, how do they do it? what “factor” allows cancer cells to make its own blood vessels?
- penetrates basement membrane & through lymphatic system or blood
- can develop its own blood vessels & connect w patient’s blood supply through secreting vascular endothelial growth factor
