cancer Flashcards

(91 cards)

1
Q

Whats the normal function of an oncogene and how are they activated in cancers

A

Control cell proliferation, or apoptosis, or both.

Activated by 1) structural alterations (mutation or gene fusion). 2) juxtaposition to an enhancer element. 3) amplification

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are the 6 classes of oncogenes and give an example

A

1) growth factor receptors: EGFR, PDGFRA/B, RET.
2) Signal tranducers: N/H/KRAS, ABL1, BRAF, AKT.
3) Growth factors: PDGFA/B, WNT.
4) Inhibitors of apoptosis: BCL2, MDM2.
5) Transcription factor: MYCN, MYC, EWSR1.
6) Chromatin remodellers: KMT2A.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Give an example of an oncogene thats activated by amplification

A

ERBB2 (HER2): breast cancer.

MYCN: neuroblastoma.

MET: renal cell carcinoma, glioma.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Give an example of an oncogene thats activated by mutations

A

H/K/NRAS: metatstatic CRC, lung, breast, bladder, AML.

BRAF: malignant melanoma, metastatic CRC, hairy cell leukeamia.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Give an example of an oncogene thats activated by chr rearrangements

A

Chimieric gene: BCR-ABL1

Position effect: MYC-IGH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Whats the normal function of a tumour suppressor gene and what are the types

A

involved in the restrain of cell growth and stimulate cell death.

Gatekeeper genes: TP53, Rb, CDKN2A, APC.

Caretaker genes: MLH1, MSH2,6.

(?) Landscaper genes: PTEN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Discuss CDKN2A function

A

encodes 2 structurally unrelated proteins:

p16INKA: inhibits CDK4,6: LoF causes Rb activaton

p14ARF: destabilises MDM2 & maintains TP53 levels: LoF increases MDM2 levels causing loss/destruction of TP53.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

discuss TP53 function

A

in the centre of the network of signalling pathways essential for growth, regulation and apoptosis. its induced by genotoxic and non-genotoxic stress.

stressed cell: TP53: phosphorylated and acetylated: migration and increased levels of TP53.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

discuss TP53 LoF types

A

mutations upstream of TP53: ATM & CHK2.

deletion of TP53: CLL

TP53 mutation: 50% somatic cancers: mutant p53: dominant negative effect (forms tetramers)

mutations downstream of TP53: PTEN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Name as microRNA TSG and its asscoiated cancer

A

miRNA-145: NSCLC

iRNA-34 family: lumg cancer

miRNA- 15a/16-1 cluster: B-CLL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what inherited and sporadic cancer is APC associated with

A

FAP: familial adenomatous polyposis

colorectal cancers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what inherited and sporadic cancer is MLH1, MSH2,6 associated with

A

HNPCC: Hereditary non polyposis colorectal cancer

CRC, gastric, endometrial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what inherited and sporadic cancer is VHL associated with

A

Von Hippel Lindau syndrome

kidney cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the two forms of anti EGFR agent used fro treatment

A

1) monoclonal antibody against the extracellular domaina: cetuximab.
2) competitive TKI of the receptor: erlotinib, gefitinib

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are the single stranded repair mechanisms and what genes are associated with them

A

Checkpoint activated by ATR.

1) Mismatch repeair (caused by replication errors): MSH2,6, MLH1
2) Nucleotide excision repair (caused by Uv radiation): XPC.
3) Base excision repair (caused by ionising radiation, oxygen radicals, anti-tumour agents): PARPi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the double stranded repair mechanisms and what genes are associated with them

A

Checkpoint activated by ATM.

Caused by ionising radiation, oxygen radicals, anti-tumour agents.

1) NHEJ: LIG4 syndrome, XLF-SCID.
2) Homologous recombination: BRCA1,2 (Rad51)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Whats Synthetic Lethality

A

when the contribution of mutations in 2 or more genes causes cell death, but a mutation in 1 gene dosen’t.
Useful when known target is difficult to target by small molecules- target SL partner instead.

PARPi (paradigm for SL) in Breast cancer. PARP is a DNA repeair enzyme. PARPi have few side effects.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Name 3 disorders that have predisposition to cancer

A

Fanconis. Ataxia telangiesctasia. Xeroderma pigmentosum.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are the advantages are liquid biopsies

A

1) detection of early and metastatic disease (serial sampling- real time analysis)
2) capture entire heterogeneity of disease
3) molecular characterisation to aid prognosis
4) prediction and monitoring of treatment response.
5) Detection of eveloving resistance mutations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

how are circulating tumour cells detected

A

require an enrichment step: usually an immunological one: use epithelial marker: EpCAM (absent on blood cells). Use immunological bead capture system: EpCAM antibody conjugated to a magnetic bead.

Allows morphological ID of malignant cells: analysis entire genome of the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

why carry out MRD

A

1) high resolution determination of efficacy of therapy.
2) allow target driven titration of dose/duration of therapy.
3) determine prognosis after completion of standard treatment.
4) relapse risk after induction: allow optimal consolidation therapy.
5) spare toxicity and cost of SCT in low relapse risk pts.
6) assignment of appropriate maintenance therapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What MRD methods are there

A
FISH (0.3-5%).
q rt-PCR (10-4-10-5).
q-PCR.
Tandem duplication PCR (FLT3-ITD only).
Flow (10-4).
QF-PCR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what gets monitored in ALL MRD

A

MRD test 2-3 weeks post remission induction therapy= good predictor of outcome.

Generally by Flow.

rt-PCR: IG-TCR rearr (90% pts- unique)/ gene fusion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what gets monitored in CML MRD

A

K: (>5%) 20mets.

iFISH (0.5%) 100 cells

q rt-PCR: (1x10-5) PB or BM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what gets monitored in Lymphoma MRD
all NHL are monitored by IG-TCR rearrangement MCL: early acheivement of MRD: highly predictive for PFS (100%) when treated with CALGB 50403
26
what gets monitored in AML MRD
gene fus. tandem duplication PCR. WT1 mRNA expression. flow
27
what are the challenges of tumour mutation testing
Hetergeneity of sample (intra and inter). Tumour load in sample & % tumour cells with mutation. Availability of tumour. FFPE tissue (qual and quant DNA).
28
name two NGS tumour panels and 2 SNP arrays
SureSeq tumour Panel (OGT) 60 genes. Illumina Cancer SNP panel OGT CytoSure Haematological Cancer+SNP. Agilent Human Genome CGH+SNP microarray
29
Whys detecting LOH important in cancer
Acquired LOH: duplication of an activating somatic mut or homozygosity of a disease prone minor allele in the germline. increase/decrease gene expression by expression/ repression particular methylation pattern
30
whats an aim of the use of SNP arrays on cancers
development of a molecular classification scheme to complement histology in diagnosis
31
what is stratified medicine
using molecular characteristics of a patient to enable targeted treatment to improve clinicial care
32
What are the advantages of stratified medicine
1) Enable clinicians to make informed decisions. 2) cost saving for the NHS. 3) improve outcomes. 4) reduce side effects.
33
what are some of the barriers to stratified medicine
Genetics: 1) TaT of results. 2) having reliable gene panels for testing. 3) cost of testing in the financial climate. 4) infrastructure to carry out tests. 5) genotype- clinical info databases to enable informed reporting. therapy: 1) cost of developing the therapies for a small cohort of patients. 2) ability to trial/develop new therapies in an acceptable time frame. 3) Detection of new bio-markers if labs are only doing panels (need to be research).
34
Name the gene and the drug used in Breast Cancer
ERBB2 (HER2) amplification (20-25%): Trastuzamab (herceptin) BRCA1,2 germline: PARPi
35
Name the gene and the drug used in Malignant melanoma
BRAF mut V600E (60%): Vemurafenib (inhibits BRAF). c-KIT mut (30%): Imatinib TKI
36
Name the gene and the drug used in Colorectal Cancer
KRAS wildtype (30% mCRC): EGFR monoclonal anitbodies: cetuximab, panitumumab.
37
Name the gene and the drug used in NSCLC
EGFR mut (16.6%): gefitinib, erlotinib, osimertinib (T790M resistance). KRAS mut (22%): No target treat (chemo). EML4-ALK (4-6%): crizotinib TKI. ERBB2 amp (3%): trastuzamab
38
whats the ALK rearrangement in NSCLC
inv(2)(p21p23) EML4-ALK
39
what percentage of lung cancer is NSCLC
85-90%. adenocarcinoma. squamous cell carcinoma
40
what are the two variants that affect warfarin dosage
CYP2C9: CYP2C9*2 AND CYP2C9*3: strong risk of over-anti-coagulation. VKORC1: AA (low dose), AB (intermediate dose), BB (high dose). B: wt. A: variant: most common: 1173 C>T
41
whats the drug and variant associated with HIV treatemnt
Abacavir: HLA-B*57:01. higher in Caucasian popn if have this variant allele at risk of developing HSR in 1st 6 wks treatment. HSR (immunological hypersensitivity syndrome): fever, rash, fatigue, respiratory problems)
42
Name a CLL trial
RIALTO PiCLLe: del/mut ATM: PARPi
43
Name AML trial
AML18 over 60yrs. AML19 under 60yrs. MyeChild01: childhood AML (upto 18yrs)
44
Name CML trial
SPIRIT 3: imat Vs Nilot Vs ponat. After about 4 yrs look at reducing/stopping treatment
45
what tissues/sites are carcinomas found
epithelial cells: breast, colon
46
what tissues/sites are sarcomas found
muscle, bone, nerves, blood vessels. soft tissue.
47
what abnormality is associated with Alveolar Rhabdomyosarcoma ARMS
t(2;13)(q35;q14) PAX3-FOXO1 (60%) t(1;13)(p36;q14) PAX7-FOXO1 (20-40%) Diagnostic of ARMS. more aggressive than ERMS
48
what abnormality is associated with Embryonal Rhabdomyosarcoma ERMS
Not diagnostic of ERMS hyperdiploidy: 2, 8,11,12,13,20. del/LOH 11p15 better prognosis to ARMS. more common in younger children (
49
what is Rhabdomyosarcoma
a sarcoma of the connective tissues (skeletal muscle progenitors) Most common form os soft tissue sarcoma in children and adolescents (
50
discuss demoplastic small round cell tumour
t(11;22)(p13;q12) EWSR1-WT1 highly maliganant mesenchymal neoplasm of abdominal cavity. median age 21yrs poor prognosis (survibal
51
Discuss synovial sarcoma
95% SS: t(X;18)(p11;q11) SSX1 (75%), SSX2(25%)- SS18 (SYT) FISH: SYT BA highly malignant. mesenchymal spindle cell tumour with epithelial differentiation. seen in extremities age 15-30yrs.. SSX1: poorer prog to SSX2
52
discuss infantile fibrosarcoma
t(12;15)(p13;q26) ETV6-NTRK3 soft tissue tumour seen in children arising from fibroblasta. much more favourable prognosis. mortality rate 4-25%.
53
discuss medulloblastoma
i(17q) (50%). MYCamp (10-20%) malignant invasive embryonal tumour of the cerebellum. both chr abns: poor prognosis, if have both very poor prognosis.
54
discuss Rhabdoid tumour
del/unbalanced t of 22q11.2 SMARCB1 commonly lethal childhood tumour. 80% cases
55
discuss liposarcoma
soft tissue lipogenic tumour seen in adults 20%
56
discuss myxoid liposarcoma
t(12;16)(q13;p11) FUS-DDIT3 FISH: DDIT3 BA .t(12;22)(q13;q12) DDIT3-EWSR1
57
discuss well differentiated liposarcoma
40-45% of all liposarcomas 80%: supernumerary marker with amplified sequence for MDM2 (12q15) and CDK4 genes FISH: MDM2
58
discuss Wilms tumour
malignant neoplasm of the kidney. most common genitourinary malignancy in children. 90% over 10yrs old. survival: 85%. WT1: 11p13 if bilateral tumours: consider WT1 mutation testing
59
discuss retinoblastoma
99% children w. intraocular Rb survive. 90% retain vision in at least 1 eye. 40% hereditary. 60% sporadic. del(13q14) in 5% uni- and 7.5% bi-lateral Rb
60
whats the good neuroblastoma prognosis group
near triploidy. (55%). +7, +17 (and -3, -4, -11, -14) excellent survival (near 100%). infants: spontaneous regression older children: spontaneous maturation
61
whats the poor neuroblastoma prognosis group
di-/tetra-ploid. (45%) majoirty: unbalanced abns: MYCN amp, del(1p36), del(11q), +17q MYCN and del11q: mutually exclusive w. diff expression profiles. MYCN amp: very poor: rapid tumour progression (del1p36, +17q) del(11q23): unfavourable outcome
62
what is the recommended genetic markers to be tested for in neuroblastoma
MYCN amp. del(11q23). ploidy level.
63
discuss gliomas
70% of CNS tumours (gliomas and meningiomas). 2nd most common form cancer in children less 15yrs (25%) astrocytoma, oligoastrocytoma, oligodendroglioma, gliosarcoma, glioblastoma, epenymoma
64
discuss oligodendrogliomas
better overall survival and outcomes than other glioma subtypes. co-deletion: 1p/19q (80% cases) 80-90% pts with co-deletion respond better to treatment. commonly mutated genes: IDH1,2 (70%) often with 1p/19q loss. TP53, PIK3A
65
discuss glioblastoma
seen in adults (45-70yrs). very poor prognosis (survial 14.6mnths) common genetic and epigenetic abns seen
66
what epigenetic changes seen in glioblastoma
hypermethylation of MGMT, GATA6, CASP8 MGMT: better PFS and OD (50% cases) MGMT: repair enzyme thats resistant to alkylating agents. hypermethylation: MGMT silenced: cells more sensitive to alkylating agents- apoptosis. MS-PCR: prognostic test for blastomas
67
what are the 2 genetic profiles for glioblastoma
type1) TP53 inactivation: seen in secondary tumours, may see MDM2 amp, CDKN2A silencing. type2) EGFR amp/overxpression: de novo tumours. PTEN mut often seen.
68
discuss Ewings
ewing sarcoma/PTEN (primative neuroectodermal tumour) highly agressive primary tumour of the bone (pelvis, femur)- undifferentiated small round cell phenotype. 5yr DFS: 60-7-% (localised) / 10-30% (metastasized)
69
discuss genetics of ewings
85%: t(11;22)(q24;q12) 5'EWSR1-3'FLI1 10-15% t(21;22)(q22;q12) EWSR1-ERG
70
discuss the ESWR1 oncogene
EWSR!: TET2 family. FLI1: transcription factor normally functions in heamatopoietic, vascular, neural-crest development. ESWR1-FLI1 fusion: constitutively expressed from native EWSR1 promoter (FLI1 is non functional in Ewing sarcoma cells). EWSR1wt is disrupted in sarcoma cells (dominant negative effect) resulting in haploinsufficiency of EWSR1.
71
what rearrangement is seen in myxoid chondrosarcoma
t(9;22)(q22;q12) NR4A3-EWSR1 .t(9;17)(q22;q11) NR4A3-TAF15
72
what rearrangement is seen in Clear cell sarcoma
t(12;22)(q13;q12) ATF1-EWSR1
73
According to BPG what do you do if you detect 1 cell with -7 in a myeloid neoplasm
Take count up to 30 screening for 7s OR FISH to confirm clonality
74
If have a neuroblastoma with near triploidy and segmental aberrations and/or MYCN amplification what's the prognosis
Aggressive behaviour (poor)
75
What aberrations are seen in Wilms tumour
LOH: 16q, 1P 22q (adverse outcome). chr abns: -1p, -16q, der(16)t(1q;16q), -22. Future direction: +1q (seen in 30%). Association between +1q and LOH 1p due to der(16) above.
76
Discuss Wilms tumour and 11p15 methylation status
3 categories: 1. Retention of imprinting (no changes). 2. Loss of imprinting. 3. LOH (due to del/dup). Significant association between LOH 11p15 and relapse.
77
What percentage of Wilms tumours have WT1 muts
Sporadic: 10-20% Germline: almost 100%
78
What syndrome are ass with Wilms
WAGR; Denys-Drash; Frasier's syndrome >10% Beckwith-Wiedemann
79
Name the rarer Ewing rearrangements
t(7;22) EWSR1-ETV1 t(17;22) EWSR1-E1AF t(2;22) EWSR1-FEV inv(22) EWSR1-ZSG .t(16;21)(p11;q22) FUS-ERG
80
Discuss dermatofibrosarcoma protuberans and giant cell fibroblastoma
.t(17;22)(q22;q13) PDGFB- COLIA1
81
Discuss inflammatory myofibroblastic tumour
TPM3-ALK t(1;2)(q22;p23) TPM4-ALK t(2;19)(p23;p13) .t(2;17)(p23;q23) and t(2;11)(p23;p15) ALK-CARS
82
Discuss papillary renal cell carcinoma
+7,+17, disomy 1
83
Discuss renal cell carcinoma with Xp11 translocation
Xp11.2 TFE3 Usually t(X;1)(p11.2;q21) TFE3-PRCC
84
What are the variants of renal cell carcinoma with Xp11 translocation
.t(X;1)(p11.2;q34) TFE3-PSF; t(X;17)(p11.2;q25) TFE3-ASPL; t(X;17)(p11.2;q23) TFE3-CLTC
85
Discuss schwannoma
22q deletion
86
What abnormalities other then inv(2) are seen in lung adnocarcinomas
6q22.1 ROS1; 10q11 RET. EGFR; MET; ERBB2
87
What carcinomas is ERBB2 amplification seen in
Breast carcinoma; gastric carcinoma FISH: ERBB2, D17Z1
88
What rearrangements are seen in extraskeletal myoepithelial carcimona/tumour
22q12 (EWSR1) rearrangements .t(6;22)(p21;q12) POU5F1 .t(1;22)(q23;q12) PBX1
89
Discuss low grade myxoid fibrosarcoma
FUS-CREB3L2 t(7;16)(q34;p11)
90
WHAT TECHNIQUE CAN BE USED TO detect methylation status of MGMT in glioblastoma
MS-MLPA, pyro, MS-PCR
91
What chromosome abnormalities are seen in hepatocarcinoma
Loss/gains Losses: 4q; 8p; 13q (Rb1); 16q (AXIN1); 17p (TP53) Gains: 1q; 8q; 20q