IMBECU   20882
INSTITUTO DE MEDICINA Y BIOLOGIA EXPERIMENTAL DE CUYO
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
HER-2/neu and β-catenin protein location: importance in the prognosis of breast cancer patients and their correlation when breast cancer cells suffer a stressful situation
Autor/es:
CUELLO-CARRION D; JORGE SHORTREDE; ALVAREZ OLMEDO D; N. CAYADO-GUTIÉRREZ,; CASTRO G. N.; GAGO EF; CIOCCA L; FANELLI MA; CIOCCA D.R.
Reunión:
Congreso; VI International Congress on cell stress society international; 2013
Resumen:
Breast cancer cells show β-catenin/HER-2 interaction, both proteins cooperate inducing
mammary tumors in transgenic mice. In addition, β-catenin interacts with HSP27. We
reported a striking membrane β-catenin/HER-2 expression in transgenic mice (in contrast to
human breast cancer where β-catenin frequently appears in the cytoplasm). We report here the
clinical significance of β-catenin/HER-2 association in our tumor bank by
immunohistochemistry. These patients did not receive specific anti-HER-2 therapy. In
?normal? glands adjacent to tumors, β-catenin was expressed in the membrane only (HER-2
was absent). In hyperplastic lesions and in in situ carcinomas β-catenin appeared in the
membrane and cytoplasm, and some cells lost its expression. HER-2 appeared in in situ
carcinomas only. In invasive carcinomas β-catenin appeared: a) at the cell membrane
(completely surrounding the tumor cells), or b) as fragmented membrane immunostaining
with or without cytoplasmic granules. Interestingly, in the HER-2 positive cancer patients,
when the tumors expressed β-catenin in the form of continuous membrane immunostaining,
there was a strong association with good prognosis. To further explore the dynamics of β
-catenin/HER-2 interaction, we examined the behavior of these proteins when MCF-7 cells
were exposed to a stressful situation (Cd administration). Cd induced a β-catenin shift from
the cell membrane to the cytoplasm, at Cd concentrations that affected long-term survival.
HER-2 was also affected by Cd administration, the protein remained at the cell membrane but
its expression increased significantly in the cytoplasm. These studies point to the links
between β-catenin and HER-2 and represent a step towards more individualized
diagnostic/treatment concepts in human breast cancer.