Genetics and Genomics Determinants of Cancer Exam Questions and Answers.
cancer is the result of... - Answersaccumulation of gene mutations
cancer is the _____ most common cause of death in the US - Answers2nd
most cancer deaths occur between the ages of - Answers55-75
four classes of tumor-related genes: - Answers1. proto-oncogenes
2. tumor suppressor genes
3. DNA repair genes
4. apoptosis genes
when do somatic/acquired mutations occur? - Answersafter conception
are acquired/somatic mutations ever present in the germline? - Answersno
when do germline mutations occur? - Answersbefore conception
synonymous mutations = - Answerssame amino acid
are synonymous mutations silent? - Answersnot always (even though it's the same AA,
they can affect mRNA degradation or translational efficacy)
missense mutations can be - Answersconservative or nonconservative
a "conservative" mutation is - Answersa missense mutation that has the same
polarity/charge as the original amino acid
a "nonconservative" mutation is - Answersa missense mutation that has a different
polarity/charge from the original amino acid
a silent mutation is a type of synonymous mutation that does not lead to -
Answersphenotypic change
the 5 germline cancer variant classifications range from - Answerspathogenic to benign
the 5 somatic cancer variant classifications range from - Answersdamaging to benign
gain of function mutations result in (2) - Answers1. overexpression
2. acquisition of a new function
are gain of function disorders usually dominant or recessive? - Answersdominant
are loss of function disorders usually dominant or recessive? - Answersrecessive
in loss of function disorders, heterozygotes with 50% function are... -
Answersasymptomatic or exhibit mild phenoytype
phenotypic changes in cancer cells (10): - Answers1. evasion of apoptosis
2. growth signal autonomy
3. insensitivity to anti-growth signals
4. sustained angiogenesis
5. limitless replicative potential
6. tissue invasion/metastasis
7. deregulation of cellular energetics
8. avoidance of immune destruction
9. genomic instability/mutation
10. tumor-promoting inflammation
neoplastic transformation - Answersconversion of normal cells to tumor cells as the
result of genetic changes
do malignant neoplasms typically arise from benign neoplasms? - Answersno
why does liver cirrhosis/chronic ulcerative colitis often lead to malignant transformation?
- Answersongoing proliferation (greater likelihood for mutation)
, neoplasms have a greater likelihood for karyotypic abnormalities, such as...(3) -
Answerstranslocations, deletions, gene amplifications
can neoplastic growth be influenced by host factors? - Answersyes (hormones)
is growth of neoplastic cells inhibited by contact with surrounding cells? - Answersno
tumor cells can bind laminin and fibronectin in connective tissues and secrete what to
invade them? - Answerscollagenases and proteases
can neoplastic cells avoid death? - Answersyes
can neoplastic cells divide indefinitely? - Answersyes
driver mutations typically occur in... - Answerscancer-related genes
most mutations in a cancer are - Answerspassenger mutations
do passenger mutations occur randomly? - Answersyes
categories of driver mutations (2) - Answers1. proto-oncogenes
2. tumor suppressor genes
under normal circumstances, the role of proto-oncogenes is: - Answerspromotion of
normal growth/survival
under normal circumstances, the role of tumor suppressor genes is: - Answersinhibition
of proliferation in response to stimuli (ex. DNA damage)
what type of mutation turns a proto-oncogene into an oncogene? - Answersgain of
function (also gene fusions or changes in expression levels)
BRAF is a - Answersproto-oncogene
CDKN2A is a - Answerstumor suppressor gene
constitutively-activating mutations in _______ have been identified in 5-10% of all
cancers - AnswersBRAF
most BRAF mutations are... - Answerssingle nucleotide changes (ex. V600E)
BRAF is usually involved in what pathway? - AnswersRas/MAPK/ERK
when the BRAF gene is mutated, it results in - Answersconstitutive action of
Ras/MAPK/ERK pathway (without ligand binding)
V600E and other mutations of BRAF activate its __________ domain - Answerskinase
(constitutively activating it)
the CDKN2A gene codes for which proteins? - Answersp14, p16
p14 and p16 are both encoded by CDKN2A and share exon... - Answers2
normal function of p14 - Answerssequester HDM2 (p53 ubiquitin ligase)
result of loss of p14 - Answersdegradation (ubiquitination) of p53
normal function of p16 - Answersinhibit CDK4/CDK6 (keeps Rb non-phosphoryated and
bound to E2F)
loss of p16 results in - Answersactivation of CDK4/CDK6 (promoting phosphorylation of
Rb/dissociation from E2F)
mutations in CDKN2A functionally inactivate which two tumor suppressor pathways? -
Answersp53, Rb
if DNA damage repair via GADD45 is successful, is p53 activated or inactivated? -
Answersinactivated (and targeted for ubiquitination via HDM2/MDM2)
if DNA damage fails to be repaired via GADD45, is p53 activated or inactivated? -
Answersactivated (induces apoptosis genes bax and IGF-BP3)
loss of both p53 alleles is found in more than _______% of cancers - Answers50
role of HDM2/MDM2 - Answersubiquitinate/degrade p53
cancer is the result of... - Answersaccumulation of gene mutations
cancer is the _____ most common cause of death in the US - Answers2nd
most cancer deaths occur between the ages of - Answers55-75
four classes of tumor-related genes: - Answers1. proto-oncogenes
2. tumor suppressor genes
3. DNA repair genes
4. apoptosis genes
when do somatic/acquired mutations occur? - Answersafter conception
are acquired/somatic mutations ever present in the germline? - Answersno
when do germline mutations occur? - Answersbefore conception
synonymous mutations = - Answerssame amino acid
are synonymous mutations silent? - Answersnot always (even though it's the same AA,
they can affect mRNA degradation or translational efficacy)
missense mutations can be - Answersconservative or nonconservative
a "conservative" mutation is - Answersa missense mutation that has the same
polarity/charge as the original amino acid
a "nonconservative" mutation is - Answersa missense mutation that has a different
polarity/charge from the original amino acid
a silent mutation is a type of synonymous mutation that does not lead to -
Answersphenotypic change
the 5 germline cancer variant classifications range from - Answerspathogenic to benign
the 5 somatic cancer variant classifications range from - Answersdamaging to benign
gain of function mutations result in (2) - Answers1. overexpression
2. acquisition of a new function
are gain of function disorders usually dominant or recessive? - Answersdominant
are loss of function disorders usually dominant or recessive? - Answersrecessive
in loss of function disorders, heterozygotes with 50% function are... -
Answersasymptomatic or exhibit mild phenoytype
phenotypic changes in cancer cells (10): - Answers1. evasion of apoptosis
2. growth signal autonomy
3. insensitivity to anti-growth signals
4. sustained angiogenesis
5. limitless replicative potential
6. tissue invasion/metastasis
7. deregulation of cellular energetics
8. avoidance of immune destruction
9. genomic instability/mutation
10. tumor-promoting inflammation
neoplastic transformation - Answersconversion of normal cells to tumor cells as the
result of genetic changes
do malignant neoplasms typically arise from benign neoplasms? - Answersno
why does liver cirrhosis/chronic ulcerative colitis often lead to malignant transformation?
- Answersongoing proliferation (greater likelihood for mutation)
, neoplasms have a greater likelihood for karyotypic abnormalities, such as...(3) -
Answerstranslocations, deletions, gene amplifications
can neoplastic growth be influenced by host factors? - Answersyes (hormones)
is growth of neoplastic cells inhibited by contact with surrounding cells? - Answersno
tumor cells can bind laminin and fibronectin in connective tissues and secrete what to
invade them? - Answerscollagenases and proteases
can neoplastic cells avoid death? - Answersyes
can neoplastic cells divide indefinitely? - Answersyes
driver mutations typically occur in... - Answerscancer-related genes
most mutations in a cancer are - Answerspassenger mutations
do passenger mutations occur randomly? - Answersyes
categories of driver mutations (2) - Answers1. proto-oncogenes
2. tumor suppressor genes
under normal circumstances, the role of proto-oncogenes is: - Answerspromotion of
normal growth/survival
under normal circumstances, the role of tumor suppressor genes is: - Answersinhibition
of proliferation in response to stimuli (ex. DNA damage)
what type of mutation turns a proto-oncogene into an oncogene? - Answersgain of
function (also gene fusions or changes in expression levels)
BRAF is a - Answersproto-oncogene
CDKN2A is a - Answerstumor suppressor gene
constitutively-activating mutations in _______ have been identified in 5-10% of all
cancers - AnswersBRAF
most BRAF mutations are... - Answerssingle nucleotide changes (ex. V600E)
BRAF is usually involved in what pathway? - AnswersRas/MAPK/ERK
when the BRAF gene is mutated, it results in - Answersconstitutive action of
Ras/MAPK/ERK pathway (without ligand binding)
V600E and other mutations of BRAF activate its __________ domain - Answerskinase
(constitutively activating it)
the CDKN2A gene codes for which proteins? - Answersp14, p16
p14 and p16 are both encoded by CDKN2A and share exon... - Answers2
normal function of p14 - Answerssequester HDM2 (p53 ubiquitin ligase)
result of loss of p14 - Answersdegradation (ubiquitination) of p53
normal function of p16 - Answersinhibit CDK4/CDK6 (keeps Rb non-phosphoryated and
bound to E2F)
loss of p16 results in - Answersactivation of CDK4/CDK6 (promoting phosphorylation of
Rb/dissociation from E2F)
mutations in CDKN2A functionally inactivate which two tumor suppressor pathways? -
Answersp53, Rb
if DNA damage repair via GADD45 is successful, is p53 activated or inactivated? -
Answersinactivated (and targeted for ubiquitination via HDM2/MDM2)
if DNA damage fails to be repaired via GADD45, is p53 activated or inactivated? -
Answersactivated (induces apoptosis genes bax and IGF-BP3)
loss of both p53 alleles is found in more than _______% of cancers - Answers50
role of HDM2/MDM2 - Answersubiquitinate/degrade p53
