p53: TUMOUR PROGRESSION AND THERAPY MARKER
TP53 is tumour suppressor gene located on chromosome region 17p13. It codes protein p53 that is responsible for cell growth regulation through inhibition of the cell cycle or promotion of apoptosis. Stress caused by DNA damage, different aberrant growth signals from the environment and expression of various oncogenes influence p53 expression and activation in both normal and cancer cells. Tumours with different cell of origin, tumours developed in different localisations and the ones present in different stages of progression often harbour p53 aberration. In chronic lymphocytic leukaemia TP53 mutation and deletion have an impact on therapy response and overall response. In myeloid neoplasms p53 can be involved in disease development mechanism, but in aberrant form it can also contribute to the progression of otherwise favourable form of the disease. It’s most known role is the one in colorectal carcinoma where it represents final step of malignant neoplasm development – transition from adenoma to carcinoma. This article gives a review of p53 function in normal and neoplastic cells with special emphasis on its usefulness as a tumour marker.