Inflammation and Cancer

Question 1

What is inflammation?

Answer 1

• a defensive reaction (innate immune response) against injury caused by trauma, toxic chemicals, or invading pathogens
• a protective response but also a potentially harmful process - components of inflammation that are capable of destroying microbes can also injure bystander normal tissue
• if the inflammatory response does not reach a critical threshold of activation, the necessary mechanisms of regulation are not promoted effectively

Question 2

Which hallmark of cancer does inflammation fall under?

Answer 2

• hallmarks of cancer are acquired functional capabilities that allow cancer cells to survive, proliferate and disseminate
• this is made possible through the 2 enabling hallmarks, one of which is TUMOUR PROMOTING INFLAMMATION

Question 3

Which cells are tumours densely infiltrated with?

Answer 3

• they have associated lymphotic infiltrates
• beneficial immune infiltrate is associated with CD8+ cytotoxic T cells (a cytotoxic T lymphocyte (CTL))

Question 4

How is anti-tumour immunity mediated?

Answer 4

• mediated primarily by CD8+/CDL cytotoxic cells
• a dendritic cell phagocytoses a tumour antigen
• this leads to the activation of tumour antigen specific CD8+ T cells
• these cells are tumour specific and migrate to the tumour
• the CTL kills the tumour

Question 5

How can tumour cells evade the immune response?

Answer 5

1. Failure to produce tumour antigen = if the tumour cell doesn’t produce a cell surface antigen, T cells will not be able to recognise them
2. Mutation in MHC gene = MHC gene does not mark tumour as a pathogen so T cells don’t recognise them
3. Tumours secrete immunosuppressive proteins = effects T cells abilities and its activation is inhibited