p53
p53 is a tumour suppressor gene located on chromosome 17p. It is the most commonly mutated gene in breast, colon and lung cancer
p53 is thought to play a crucial role in the cell cycle, preventing entry into the S phase until DNA has been checked and repaired. It may also be a key regulator of apoptosis
Li-Fraumeni syndrome is a rare autosomal dominant disorder characterised by the early onset of a variety of cancers such as sarcomas and breast cancer. It is caused by mutation in the p53 gene
p53 is thought to play a crucial role in the cell cycle, preventing entry into the S phase until DNA has been checked and repaired. It may also be a key regulator of apoptosis
Li-Fraumeni syndrome is a rare autosomal dominant disorder characterised by the early onset of a variety of cancers such as sarcomas and breast cancer. It is caused by mutation in the p53 gene
Key points
p53 is a tumour suppressor gene- Location: Chromosome 17p13.1
- Protein product: p53, a transcription factor
- Monitors DNA integrity
- Induces cell cycle arrest (usually at G1/S checkpoint) to allow DNA repair
- Triggers apoptosis if DNA damage is irreparable
- Helps maintain genomic stability and prevent tumorigenesis
- Mutations in p53 are found in ~50% of human cancers
- Loss of p53 function → uncontrolled cell proliferation, resistance to apoptosis, increased genomic instability