Cancer immunotherapy

Question 1

Tumour-infiltrating lymphocytes

Answer 1

Immune cells found in and around tumours
Recognise tumours as altered self
Incidence of cancer higher in immunosuppressed patients

Question 2

Types of immunotherapy

Answer 2

Immune checkpoint inhibitors
T-cell transfer therapy
Monoclonal antibodies
Cancer treatment vaccines
Cytokines (non-specific)

Question 3

Immune checkpoints

Answer 3

Prevent immune response from destroying healthy cells (dampen response)
Proteins engage with receptors on T cells to downregulate their activity
Overexpressed in cancer cells

Question 4

Immune checkpoint inhibitors

Answer 4

PDL on tumour cell interacts with PL1 on T cell to inhibit activity
Anti-PDL and anti-PDL1 antibodies disrupt interaction and upregulate immune response

CTLA-4 on T cell downregulates response to DCs. CTLA-4 inhibitors

Question 5

TIL therapy

Answer 5

Tumour-infiltrating lymphocytes
Removed from patient and tested to identify population that best recognises cancer cells
Treated with factors to induce expansion and injected back into the patient

Question 6

CAR T-cell therapy

Answer 6

Cells genetically modified to be more potent against cancer cells
Express chimeric antigen receptor
Can lead to Cytokine release syndrome
May recognise normal cells

Question 7

Chimeric antigen receptor

Answer 7

Extracellular domain recognises cancer cells (based on antigen-recognition region of antibody)
Cytosolic domains increase activation of T cell. Can have several domains
Binding leads to immunological synapse

Question 8

Monoclonal antibodies

Answer 8

Target systemic radiotherapies to cancers
Block signalling from receptor tyrosine kinases (Herceptin)
Aid immune system to recognise and destroy cancer cells

Question 9

Cancer treatment vaccines

Answer 9

Treat, not prevent cancer
Made from patient’s own tumour cells to cause an immune response against specific patient cancer
Tumour-associated antigens found on cancer cells of a specific type
From a patient’s dendritic cells

Question 10

Immune-modulating agents (cytokines)

Answer 10

Recruit and activate immune cells
Interferons (INF-alpha activates DCs and NKs)
Interleukins (IL-2 boosts CTL and NK cell number)
IL-7 and IL-15 enhance tumour cell survival

Question 11

Oncolytic viruses

Answer 11

Modified to selectively replicate within cancer cells without damaging normal cells.
Can use adenoviruses