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Figure 2. The role of TP53 in the PI3K/AKT signalling pathway. RTKs are activated by hormones and growth factors, leading to the recruitment and phosphorylation of PI3K. PDK1 is then recruited to AKT at the PH domain. Cell cycle, survival, migration and apoptosis regulation occur as a result of AKT signalling pathway activation. AKT is also activated by mTORC₂ and mTORC₁ is activated by phosphorylated AKT, promoting protein translation and cell growth. Hdm2 regulates P53 in normal healthy cells, resulting in low levels. P53 regulates PTEN, inhibiting PI3K phosphorylation and AKT activation. AKT may enhance the function of Hdm2 and PTEN may prevent P53 degradation via AKT pathway inhibition. P53 binds to PI3K to inhibit PIK3CA and mutations in TP53 may result in PIK3CA hyperactivation and subsequent PI3K signalling pathway activation. AKT: Protein kinase B; PTEN: phosphatase and tensin homolog.