Figure 7. Diagrammatic representation of PI3K/AKT/mTOR signalling pathway detailing tested drug targets and overall ranking table.

Upon activation by receptor tyrosine kinase, PI3K lipid kinases are recruited to the plasma membrane where they phosphorylate PIP₂ to form PIP₃. Once phosphorylated, the second messenger PIP₃ can bind and activate AKT which can then trigger an array of downstream signalling events. The site of action tested drugs is indicated and the most effective drugs are depicted in red, and underlined drugs are in clinical trial for ocular indications (A). Table illustrates the overall ranking of the top PI3K/AKT/mTOR inhibitor combinations in the ISV, HV, OKR, LM and MTT experimental assays (B).