Cancer genetics Flashcards
pancreatic cancer is what type of trait
autosomal dominant possesing a mutant palladin gene
abnormal proliferation of cancer cells produces
a tumor that crowds out normal cells
what type of cancer has the highest cases every year
breast
what type of cancer has the highest death
158,080
what is a distinct mass of abnormal cells
tumor formation
what is this called when a tumor cell remains localized
benign tumor
what is this called when a tumor cells invade other tissues
malignant tumor
when tumor cells induce secondary tumor is called
metastasis
what are genetic evidence for cancer
carcinogens, radiation, chromosomal abnormalities
what did Alfred Knudson proposed
that retinoblastoma results from two seperate genetic defects, both which are necessary for growth
through clonal evolution tumor, cells acquire multiple mutations to allow them to become
increasingly aggressive and proliferative
dominant-acting mutations, stimualtory genes that cause cancer are called
Oncogenes
what genes are responsible for basic cellular functions in normal cells, when mutated act as oncognes
proto-oncogenes
when proto-oncogenes are mutated, tehy are called
oncogenes
what genes are recessive-acting mutations, inhibitory genes that are inactive
tumor-suppresor genes
stimulatory genes are , inhibitory genes are
oncogenes,tumor-suppresor genes
why are people heterozygous to a tumor-supressor gene predisposed to cancer
because the loss of the wild type allele leads to loss of tumor suppressor activity
what are some mutations in genes that control the cycle of cell division
CDKs, cyclins
G1-to-S transition
Retinoblastoma protein (RB)
G2 to M transition
MPF
Spindle assembly checkpoint
what protein helps control the progression through the G1/S checkpoint
RB protein by binding transcription factor E2F
progression through G2/M checkpint is regulated by
cyclin B
what signals trigger cascade of intracellular reactions producing a specific response
signal transduction pathways
what pathway conducts signals from growth factors and hormones to the nucleus and stimulates cell cycle
Ras-signal-transduction
ACtivated Ras activates»»> which activates a protein»_space;»> which activates»_space;»>
Raf,MEK, MAP kinase
Activated MAP kinase moves into
the nucleus and activates transcription factors
mutations that lead to increased mutations in other genes
DNA repair gene
what reduces the expression of many miRNAs
MicroRNAs
mutations that drive cancer process
Drivers
mutations arise randomly during cancer but to not contribute to cancer progression
passengers
alternations to DNA methylations are seen in many cancers as
hypermethylation or hypomethylation
colorectal cancer arises from
sequential mutations of a number of gene
if initial mutations stimulate cell division and lead to a small benign polyp. what does additional mutations do
they allow the polyp to enlarge and invade the muscle layer spreading to other sites
what chromosomal inability may remove or disrupt gene that suppress tumors
deletions
what may break tumor suppressor genes or move genes to position next to different regulatory sequences altering their expressions
inversions and translocations
a reciprocal translocation between 9 and 22 causes
chronic myelogenous leukemia
a reciprocal translocation between 8 and 14 causes
burkitt lymphona
a change from the wild type in the number of chromosomes, mostly increase or decrease
aneuploidy
retroviruses can cause cancer by
mutating and rearranging proto-oncogenes
inserting strong promoters near proto-oncogenes