Interaction between the nuclear factor kappa b (NF-kB) and the estrogen receptor alpha (ERa) in the cellular senescence process during the development of estrogen-induced pituitary tumors

GRONDONA EZEQUIEL; PETITI JUAN PABLO; DE PAUL ANA L; SOSA LILIANA DEL VALLE; GUTIÉRREZ, SILVINA; MONGI BRAGATO BETHANIA; CARREÑO LUCIA; TORRES ALICIA I

Mar del Plata

Congreso; LXI REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE INVESTIGACIÓN CLÍNICA (SAIC); 2016

Evidences from our group demonstrated the emergence of cellular senescence process as a growth control mechanism during the progression of estrogen-induced pituitary tumors. Also, estrogen exerts a modulatory action on pituitary cells proliferation. Considering the preponderant role of NF-kB (p65) in cellularsenescence and points of convergence between ERa and NF-kB signaling pathways in cell cycle control, we evaluate the contribution of the interaction between these two proteins in the pituitary senescence in experimental pituitary tumors. Wistar adult male rats were implanted subcutaneously with silastic capsulescontaining estradiol benzoate (30mg) for 10, 20, 40 and 60 days (E10-60). The control group was implanted with empty capsules. Subsequently, ERa:NF-kB immunoprecipitation was performed at the different stages of tumoral development. NF-kB and IkBa levels were also determined from nuclear and cytosolic fractions by Western blot. The ERa:NF-kB co-localization was analyzed by immunofluorescence (IF) and transmission electron microscopy (TEM). Statistical analysis: ANOVA-Fischer test (p