Cancer Cell Signalling (Tumbarello)

Question 1

How do cells make decisions?

Answer 1

Using cell signalling

Cells must continually sense and respond to environmental cues
- Metabolites, hormones, presence of other cells, pathogens…
- Cells perceive their state and adapt using signalling
- Cells make important decisions based upon their surroundings e.g. proliferate or die

Question 2

Why do we study cell signalling in cancer cells

Answer 2

Cell signaling is altered in most cancers

• Signaling turned on and unresponsive to inhibition
• Volume of signaling increased
• Signaling at wrong time or place

Alterations of cell signaling enable the cell to evade normal regulatory controls

Question 3

What are oncogenes and tumour supressors?

Answer 3

Oncogenes
- Capable of cellular transformation leading to cancer
- Derived from proto-oncogenes (in normal cells) typically through mutation or over-production
- Encode oncoproteins, typically function as receptors or other components of cell signalling pathways

Tumour suppressors
- Suppresses or controls proliferation
- Mutations lead to loss of function (typically recessive), removal of inhibition
- Encode proteins with diverse functions in regulation of cell cycle, apoptosis, signaling