Signs of cellular senescence in estrogen-induced pituitary hyperplasia

SABATINO ME; PETITI JP; SOSA L; GUTIÉRREZ S; LATINI A; TORRES, A.; DE PAUL AL

Rio de Janeiro

Congreso; 10° Congreso Internacional de Biología Celular y 16° Reunión de la Sociedad brasilera de Biología Celular; 2012

Sociedad brasilera de Biología Celular

Pituitary adenomas are benign tumors with low prevalence of malignant transformation. We hypothesize the involvement of senescence as protective anti-tumoral cell mechanism and we aimed to determine its contribution in estrogen-induced pituitary hyperplasia. Wistar male rats were treated by subcutaneous implantation of estradiol benzoate (30 mg) for 10, 20, 40 and 60 days. Empty capsules were implanted in controls. By immunodetection of Ki67 and flow cytometry DNA analysis we detected estrogen-induced pituitary hyperplasia with a biphasic response: a significant proliferation rise after 10 and 20 days followed by its decrease after 60 and 80 days of treatment (p