Question

. A patient is diagnosed with lung cancer. The biopsy sample form the tumor shows that the tumor is p53 mutant, but the peripheral blood DNA contains wild type DNA. Please discuss the outcome of radiotherapy for this patient

Answer 1

Answer- Radiotherapy methods treat cancer by directly targeting DNA. When the DNA of the tumour cells gets damaged beyond repair, they stop dividing or die. These dead cells are then broken down or removed by the various proteins in the cells.

While, p53 is one such tumor-suppressor gene that plays a role in the repair of the DNA of these damaged cells, controls cell cycle arrest or apoptosis. Even functional p53 has been used to determine the radiosensitivity of these cancerous cells.

So, If the p53 muation is localized to only the benign tumour, it can impair the apoptosis caused due to the radiotherapy as the p53 mediated pathways become ineffective. And, hence the cancer treatment will be less efficient with p53 mutation.