Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

4 CAN > 16 Tumour Immunology > Flashcards

16 Tumour Immunology Flashcards

1
Q

What 2 points of evidence support tumour protective immunity in humans?

A

immunosuppressed individuals more frequently develop cancer

the presence of immune cells within some tumors correlates with improved prognosis

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

What is cancer immunosurveillance?

A

immune system can recognise precursors of cancer and in most cases destroy these precursors before they become clinically apparent

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

What is cancer immunoediting?

A

the immune system not only protects the host frrom tumour development but also sculpts or edits the immunogenicity of tumours that may eventually form

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

What are the 3 E’s of cancer immunomodelling?

A

Elimination
Equilibrium
Escape

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

Give an example of a positive costimulatory signal mediator

A

CD28 : CD80/86

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

Give 2 example of negative costimulatory signal mediators

A

CTLA-4 : CD80/86

PD-1 : PD-L1/2

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

Give 3 examples of types of tumour-associated antigens

A

mutated self-proteins

Aberrantly or overexpressed self-proteins

lineage specific antigens

Abnormal post-translational modification of self-protein

Viral proteins

tumour endothelial markers (stroma)

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

Name 3 factors which make a good target antigen for tumour immunotherapy

A

tumour specific reduced toxicity
shared amongst patients with the same and different tumour types
critical for tumour growth/survival
lack of immunological tolerance

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

Which tumour associated antigen is a good example of all the factors which make a good target antigen for tumour immunuotherapy?

A

mutated self-proteins

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

Generally, which tumour associated antigen is a poor example for most of the factors which make a good target antigen for tumour immunotherapy?

A

lineage specific antigens

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

What brings protein fragments into the RER?

A

TAP transporter

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

Name 7 general mechanisms whereby tumours might escape the immune response

A

Loss of HLA class 1 expression

Reduced expression of other molecules involved in antigen processing/presentation

Loss of costimulatory molecule expression

loss of adhesion molecule expression

loss of target antigen
inhibiting t cell infiltration

immunosuppression at the tumour site

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

Loss of which adhesion molecule expression may allow tumours to escape the immune response?

A

ICAM1

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

The loss of target antigen allowing tumours to escape the immune response is found in what cancer?

A

melanoma

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

How might inhibiting T cell infiltration allow tumours to escape the immune resopnse?

A

endothelin B receptor expression on the tumour endothelium signals to prevent modulatoin of ICAM and thereby reduces T cell adhesion to teh avascular endothelium

nitrosylation of chemokines can keep T cells from entering the tumour core

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

What is the role of TGF-beta in immunosuppression at the tumour site?

A

suppresses anti-tumouor T cell functions and induces Tregs

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

What is the role of IDO in immunosuppression at the tumour site?

A

catabolises tryptophan and can block CD8+ T cell proliferation and promote apoptosis of CD4+ T cells

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

What is the role of VEGF in immunosuppression at the tumour site?

A

inhibits differentiation, maturation, and function of local DCs so they mediate immunosuppressive effects and promote Treg differentiation

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

What is the Fas ligand in immunosuppression at the tumour site?

A

tumours engaging Fas ligand can kill Fas-expressing tumour T cells

20
Q

Name 2 sorts of cells incolced in immunosuppression at the tumour site?

A

Regulatory T cells

Myeloid-derived suppressor cells (MDSCs)

21
Q

What are MDSCs?

A

Myeloid0derived suppressor cells

a heterogenouos population of cells of myeloid origin that comprises myeloid progenitor cells adn immature macrophage, granulocytes, and DCs

22
Q

What is the role of MDSCs in immunosuppression at the tumour site?

A

Show upregulated expression of immune suppressive factors like Arginase 1 and inducible nitric oxide

these both metabolise L-Arginine

shortage of L-arginine inhibits T-cell proliferation

23
Q

Why would IL-2 be considered a chemotherapy?

A

it is a T cell growth factor

24
Q

What problem is associated with using IL-2 as a chemotherapy?

A

it’s very toxic, can’t predict which patients will benefit

25
Q

name 3 types of T cell based therapies for cancer

A

Non-specific T cell stimulation
Vaccination
Adoptive T cell therapy

26
Q

Name 2 types of non-specific T cell stimulators as therapy for cancer

A

Immunostimulatory cytokines

blockade of immunologic checkpoints

27
Q

Name 2 agents which block immunologic checkpoints

A

Ipilimumab

Pembrolizumab

28
Q

What does ipilimumab do?

A

antagonist to coinhibitory receptor CTLA4

29
Q

Who is treated with ipilimumab?

A

advanced melanoma patients

30
Q

What does Pembrolizumab do?

A

blocks PD1

31
Q

What sorts of vaccines are currently being tested in this field?

A

Tumour cells/lines (irradiated or lysates)

DC-based vaccines

defined peptides or protein antigens

32
Q

what sort of cancer might be treated with DC-based vaccines?

A

metastatic prostate cancer

33
Q

What is Provenge (Sipuleucel-T)?

A

the first cancer vaccine for metastatic prostate cancer to receive FDA approval

34
Q

What are the 2 forms of adoptive T ell therapy?

A

infusing whole T cell populations

infusing selected tumour specific T cells

35
Q

What are the 4 key advantages to adoptive T cell therapy?

A

activate T cell more effectively in vitro
fully characterised T cells
Achieve very high frequencies of reactive T cells in vivo
Support development of vaccination strategies

36
Q

What is TIL therapy?

A

Tumour-infiltrating lymphocytes therapy

37
Q

What might people receive alongside TIL therapy?

A

non-myeloablative conditioning

cyclophosphamide + fludarabine

38
Q

What do non-myeloablative conditioning therpaies do?

A

deplete the hosts’ haemopoietic system
creates space
increases cytokines encouraging infused T cell expansion

39
Q

What does TIl therapy require?

A

That the patient has T cells recognising the tumour

40
Q

name a type of cancer treatable with TIL

A

melanoma

41
Q

What are CARs?

A

Chimeric Antigen Receptors

combine:
the target specificity of an antibody
The potent cytotoxic and immune regulatory activity of a self replicating T cell

42
Q

Why is CAR so good?

A

MHC unrestricted

Targets any surface molecule (even non proteins)

43
Q

What is a key side effect of T cell-based therapies for cancer?

A

autoimmunity

TIL - vitiligo, uveitis
antagonistic antibodies for CTLA4/PD1 - severe inflammatory resopnses

44
Q

What are the 2 immune mediated mechanisms of monoclonal antibodies for cancer therapy?

A

Complement-mediated lysis

Antibody-dependent cellular cytotoxicity

45
Q

What are the 3 direct effects of monocloncal antibodies for cancer therapy?

A

blocking receptor : ligand interactions
anti-angiogenesis
Cytotoxic activity of conjugated antibodies

46
Q

Name some agents involved in anti-angiogenesis in cancer treatment

A

Avastin (anti VEGF)

Erbitux and herceptin (inhibit VEGF production)

47
Q

How might conjugated antibodies show cytotoxic activity?

A

bound to radionucleide (DNA damage > apoptosis)
bound to protein toxin molecule
bound to cytotoxic drug

4 CAN (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions