Treatment modalities for melanoma

Question 1

What is cancer immunology based on?

Answer 1

The use of the immune system to immobilize tumours

Question 2

The most important feature of the immune system

Answer 2

It is balanced

Question 3

How do cancer cells escape immune attack?

Answer 3

Take advantage of the immune-regulatory mechanisms to escape immune attack

Favour immunosuppression

Question 4

Describe the process of T cell activation

Answer 4

1. TCR recognises molecules presented on APC
2. Interaction leads to the progression of signal 1 which causes the T cell to become anergic
3. The costimulatory signal 2 activates the T cell

Question 5

What is meant when the T cells become anergic?

Answer 5

The cells stop to respond to the environment

Question 6

Example of a costimulatory signal 2

Answer 6

CD28 on T cells bind to CD80/86 on APCs

Question 7

Signal 1 is enough to induce activation of the T cell

TRUE or FALSE

Answer 7

FALSE

Full response by T cell is stimulated once both signal 1 and 2 are transduced in the T cell

Question 8

What is immunosurveillance?

Answer 8

Process that happens as the cells transition form the normal to transformed physiology.

Immune cells go into the tumour and, if the tumour is immunogenic it will be destroyed by the immune system by elimination

Question 9

What is equilibrium?

Answer 9

Process that leads to established tumour masses.

Some tumour cells survive process of elimination

Some regulatory processes shut down the T cell response (regulatory cells, CTLA-4, immunomodulatory receptors)

Leads to equilibrium in the tumour microenvironment

Question 10

Many tumour cells remain in equilibrium

TRUE or FALSE

Answer 10

FALSE

In most cases, tumour cells are able to escape equilibrium due to anti-inflammatory cytokines and mutations

Leads to formation of established tumours

Question 11

What is CTLA-4?

Answer 11

Cell surface marker

Question 12

What is the importance of CTLA-4 in cancer pathogenesis?

Answer 12

Prevents T cells from binding to the cancer cells

Question 13

How does CTLA-4 prevent T cells from binding to cancer cells?

Answer 13

Blocks CD28 from interacting with CD80/86 in APCs

Question 14

What is another master regulator in the immune response?

Answer 14

PD-1

Question 15

How is PD-1 involved in tumour progression?

Answer 15

PD-L1 immunosuppressant protein found on the surface of tumour cells

Bind to PD-1 on T cells

Suppresses T cells

Question 16

What happens to cancer cells without PD-L1?

Answer 16

T cells degranulate and release their cell contents

Stimulates an immune response

Question 17

What are cancer therapies targetting PD-L1 and CTLA-4 designed to do?

Answer 17

Block these transmembrane proteins

Allowing the T cells to kill the cancer cells

Question 18

What is the best therapy regarding anti-PD-L1 and CTLA-4 remedies?

Answer 18

Combination therapy

Question 19

What is the potential harm of cancer immunotherapies?

Answer 19

Disrupts the fine balance of the immune system

Can favour autoimmunity

Question 20

What is a potential treatment for cancer?

Answer 20

Sequencing of cancer cells

Identifying mutations that are likely to be recognised by the immune system

Form vaccines expressing the mutations

Train the immune system to recognise antigen sequences on the cells

Question 21

What are markers of regulatory T cells?

Answer 21

CD4

Foxp3

Question 22

What are markers of cytotoxic T cells?

Answer 22

CD8