INVESTIGADORES
MARTIN Gabriela Adriana
congresos y reuniones científicas
Título:
The insulin growth factor type-II receptor in rat mammary gland tumorigenesis
Autor/es:
A, SAMBUCO L, CROCI M; NÚÑEZ M, RIVERA E, BERGOC R, RANDI A, MARTÍN G.
Lugar:
San Miguel de Tucumán, Argentina
Reunión:
Congreso; XLV Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2009
Institución organizadora:
Sociedad Argentina de Investigación en Bioquímica y Biología Molecular
Resumen:
The insulin-like growth factor II receptor (IGF-IIR) is involved in
binding, internalization and degradation of IGF-II. It is now
considered to act as a tumor suppressor gene. We have previously
demostrated that three ip injections of N-Nitroso N-Methylurea
(NMU) at 50, 80 and 110 days of animals life induce malignant
mammary tumors in rats. The aim of the present study was to
investigate the expression of IGF-IIR in mammary tissue of normal
(C) and NMU-injected rats (mNMU) during the carcinogenic
process. Also, we studied the IGF-IIR expression in tumors of
NMU rats and in those of ovariectomized NMU rats (OVX). Breast
tissue specimens were processed at 60, 90, 120, 150 and 180 days.
Immunohistochemical and Western blot analysis were performed.
Results: there was no significant difference in the intensity of IGFIIR
staining and percentage of positivity were high in normal
mammary glands at all times, whilst in mNMU gland the
expression lowered progressively between 120 and 180 days.
Tumors showed a low cytoplasmatic staining vs mammary tissue.
Interestingly, tumors regressing post-OVX showed a low
malignant grade and moderate IGF-IIR staining, while tumors that
not regressed showed scarce or null receptor expression.
Conclusion: our results suggest that decreased levels of IGF-IIR are
related to the process of carcinogenesis in this experimental model