High glucose and insulin enhance uPA expression, ROS formation and invasiveness in breast cancer-derived cells
Por:
Antonio Flores-Lopez, Luis, Guadalupe Martinez-Hernandez, Maria, Viedma-Rodriguez, Rubi, Diaz-Flores, Margarita, Arturo Baiza-Gutman, Luis
Publicada:
1 ago 2016
Resumen:
Accumulating evidence indicates that type 2 diabetes is associated with
an increased risk to develop breast cancer. This risk has been
attributed to hyperglycemia, hyperinsulinemia and chronic inflammation.
As yet, however, the mechanisms underlying this association are poorly
understood. Here, we studied the effect of high glucose and insulin on
breast cancer-derived cell proliferation, migration,
epithelial-mesenchymal transition (EMT) and invasiveness, as well as its
relationship to reactive oxygen species (ROS) production and the
plasminogen activation system.
MDA-MB-231 cell proliferation, migration and invasion were assessed
using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide
(MTT), scratch-wound and matrigel transwell assays, respectively. ROS
production was determined using 2' 7'-dichlorodihydrofluorescein
diacetate. The expression of E-cadherin, vimentin, fibronectin,
urokinase plasminogen activator (uPA), its receptor (uPAR) and its
inhibitor (PAI-1) were assessed using qRT-PCR and/or Western blotting
assays, respectively. uPA activity was determined using gel zymography.
We found that high glucose stimulated MDA-MB-231 cell proliferation,
migration and invasion, together with an increased expression of
mesenchymal markers (i.e., vimentin and fibronectin). These effects were
further enhanced by the simultaneous administration of insulin. In both
cases, the invasion and growth responses were found to be associated
with an increased expression of uPA, uPAR and PAI-1, as well as an
increase in active uPA. An osmolality effect of high glucose was
excluded by using mannitol at an equimolar concentration. We also found
that all changes induced by high glucose and insulin were attenuated by
the anti-oxidant N-acetylcysteine (NAC) and, thus, depended on ROS
production.
From our data we conclude that hyperglycemia and hyperinsulinemia can
promote breast cancer cell proliferation, migration and invasion. We
found that these features were associated with increased expression of
the mesenchymal markers vimentin and fibronectin, as well as increased
uPA expression and activation through a mechanism mediated by ROS.
Filiaciones:
Univ Nacl Autonoma Mexico, Unidad Morfofisiol, Fac Estudios Super Iztacala, Ave Barrios 1, Tlalnepantla 54090, Estado De Mexic, Mexico
Hosp Especialidades Ctr Med La Raza, Inst Mexicano Seguro Social, Ctr Med Nacl Siglo 21, Unidad Invest Med Bioquim, Av Cuauhtemoc 330, Cuauhtemoc 06720, DF, Mexico
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