Exam 1 - Introduction To Oncology Flashcards
what is cancer?
5 or 6 mutations minimum to provide a cell & progeny the hallmarks of cancer
what are the 5 steps in the progression of cancer?
- precancerous dysplasia carcinoma in situ
- localized (on spot on liver)
- early locally advanced (involves more than 1 liver loves)
- late locally advanced
- metastasized
what are the 10 hallmarks of cancer?
- evading growth suppressors
- avoiding immune destruction
- enabling replicative immortality important
- tumor-promoting inflammation
- activating invasion & metastasis
- inducing angiogenesis
- genome instability & mutation
- resisting cell death
- deregulating cellular energetics
- sustaining proliferative signaling
what is an example of an intrinsic risk factor?
random errors in DNA replication
intrinsic risk factors are ________ (unmodifiable/partially modifiable/modifiable)
unmodifiable
what are the two examples of non-intrinsic risk factors?
endogenous risk factors & exogenous risk factors
between endogenous & exogenous risk factors, which is modifiable & partially modifiable?
endogenous = partially modifiable
exogenous = modifiable
what are some examples of exogenous risk factors?
radiation, chemical carcinogens, tumor causing viruses, bad lifestyles (smoking, lack of exercise, nutrient imbalances)
what are some examples of endogenous risk factors?
biologic aging, genetic susceptibility, DNA repair machinery, hormones, growth factors, & inflammation
what are intrinsic mutagens?
intrinsic risk factors - bad luck factors that interact in unpredictable ways with environmental (extrinsic) triggers to promote cancer
when is the animal getting intrinsic mutagens?
mutations are occurring during normal cell DNA replication
what is the process in which cell mutations are occurring?
every time a cell divides, each daughter cell is likely to carry at least a few hundred mutations, but most are silent
what happens if the mutations daughter cells are carrying are not silent?
ability to disable anti-cancer machinery such as tumor suppressor genes & proto-oncogenes
what is malignant transformation of cells?
genetic & epigenetic alterations & bypass of tumor suppressor mechanisms
what are some examples of tumor suppressor mechanisms?
contact inhibition, senescence (exhausted telomeres, excess DNA damage, oncogene activation), & immune surveilance
what are the 3 steps of carcinogenesis?
- initiation
- promotion
- progression
what is the initiation step of carcinogenesis?
alteration, change, or mutation of a gene - arises spontaneously or is induced by exposure to a carcinogen
what is the promotion step of carcinogenesis?
lengthy & reversible process in which actively proliferating pre-neoplastic cells accumulate during this phase
what is the progression step of carcinogenesis?
phase between pre-neoplastic & invasive neoplastic lesions
why do elephants not die of cancer?
they have an increased number of P53 genes
what is the P53 gene?
tumor suppressor gene - if a cell with faulty DNA is replicating, this gene can arrest the process & allow it to move forward only once the DNA is fixed or can kill the cell to get rid of the bad DNA