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Page 66
allied
academies
Cell Science, Stem Cell Research &
Pharmacological Regenerative Medicine
November 29-30, 2017 | Atlanta, USA
Annual Congress on
Adv cel sci tissue cul 2017 | Volume 1 Issue 2
C
ancer stem cells (CSCs) pose a challenge in cancer
treatment, as these cells can drive tumor growth and are
resistant to chemotherapy. Melatonin exerts its oncostatic
effects through the estrogen receptor (ER) pathway in cancer
cells; however, its action inCSCs is unclear. Here, we evaluated
the effect of melatonin on the regulation of the transcription
factor
OCT4
(Octamer Binding 4) by estrogen receptor alpha
(
ERα
) in breast cancer stem cells (BCSCs). The cells were
grown as a cell suspension or as anchorage independent
growth, for the mammospheres growth, representing the
CSCs population and treated with 10 nM estrogen (E2) or
10 μM of the environmental estrogen Bisphenol A (BPA) and
1 mM of melatonin. At the end, the cell growth as well as
OCT4
and
ERα
expression and the binding activity of
ERα
to the
OCT4
was assessed. The increase in number and size
of mammospheres induced by E2 or BPA was reduced by
melatonin treatment. Furthermore, binding of the
ERα
to
OCT4
was reduced, accompanied by a reduction of
OCT4
and
ERα
expression. Thus, melatonin treatment is effective
against proliferation of BCSCs
in vitro
and impacts the ER
pathway, demonstrating its potential therapeutic use in
breast cancer.
e:
James.Trosko@hc.msu.eduMelatonin decreases estrogen receptor binding to estrogen response element sites on the
OCT4
gene in
human breast cancer stem cells
James E Trosko
1
, Juliana Lopes
1
, David Arnosti
2
, Mei-Hui Tai
1
and
Debora Zuccari
2
1
Michigan State University, USA
2
Universidade Estadual Paulista, Brazil