Touching membranes – understanding how different parts of the cell communicate

Cells receive signals from their surroundings by receptors, which act like antenna located on the surface of the cell. One such antenna is called the epidermal growth factor receptor (EGFR). EGFR receives signals from the body that instruct the cells to survive, grow and differentiate. In different human cancers this antenna is continuously switched on, causing abnormal cell growth. One way to switch off this EGFR antenna is to remove it from the surface of the cell.

Dr Sara Sigismund and her team recently discovered a new way to remove EGFR from the surface of the cell. Removal of EGFR from the cell surface via this new pathway requires communication between different parts of the cell. This includes the cell’s outer layer (plasma membrane), the machinery that produces proteins (endoplasmic reticulum) and the powerhouse of the cell (mitochondria). Physical contact between these cell parts seems to be important for proper communication. It plays a role in both the growth signalling via the EGFR antenna and regulation of the way cells use energy via the mitochondria (powerhouses).

Both are processes that are hijacked by tumour cells to escape the cell’s defences against uncontrolled growth. Dr Sara Sigismund is now trying to better understand how this communication works in both healthy and cancer cells. In the future, this could provide new targets for drug development in a wide variety of cancers.