APOPTOSIS AND P53 SUPPRESSOR GENE PROTEIN EXPRESSION IN HUMAN ANTERIOR-PITUITARY ADENOMAS

Human anterior pituitary adenomas proliferate and express the p53 tumo ur suppressor gene protein, but it is not known if apoptosis (programm ed cell death) occurs, Therefore, the detection of apoptosis was under taken in tumorous human anterior pituitary tissue and compared with p5 3 protein expression, tumour type and tumour size. Apoptosis (detected by the in situ end labelling technique) and p53 suppressor gene prote in (detected by D0.1-antibody immunocytochemistry) were determined in formalin-fixed and paraffin-embedded tissue from 37 human pituitary ad enomas (2 macroprolactinomas, 9 somatotrophinomas and 26 non-functioni ng adenomas), Two normal anterior pituitaries were also included in th is study. Pre-operative tumour size was scored 1 to 4 from magnetic re sonance imaging radiology, Apoptosis was found in 7 of 29 tumours (24% ), 11% of somatotrophinomas and 33% of non-functioning adenomas, altho ugh this difference was not significant, The p53 tumour suppressor pro tein was found in 7 of 31 tumours (23%), 33% of somatotrophinomas and 19% of nonfunctioning adenomas, Apoptosis and p53 protein expression w ere not found in normal anterior pituitary. In conclusion, apoptosis o ccurs in human anterior pituitary adenomas, but no significant associa tion was found between apoptosis and p53 protein expression, tumour ty pe or tumour size.