Membrane-Bound Estrogen Receptor Alpha Initiated Signaling is Dynamin Dependent in MCF-7 Cells
- *Corresponding Author:
- Attila Patocs
HAS-SE ’Lendület’ Hereditary Endocrine Tumors Research Group
Hungarian Academy of Sciences
Semmelweis University, H-1088, Budapest, Hungary
E-mail: [email protected]
Received Date: June 22, 2017; Accepted Date: June 25, 2017; Published Date: June 31, 2017
Citation: Marczell I, Balogh P, Nyiro G, Kiss AL, Kovacs B, et al. (2017) Membrane-Bound Estrogen Receptor Alpha Initiated Signaling is Dynamin Dependent in MCF-7 Cells. J Carcinogene Mutagene 8:301. doi: 10.4172/2157-2518.1000301
Copyright: © 2016 Mbamalu ON, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Although membrane-associated estrogen receptors (mERs) have been known to play important role in steroid induced signal transmission, we still know little about their function in the estrogen induced proliferation of breast cancer cells.
In our current work we tried to separate membrane initiated estrogen receptor (ERα,) signaling from the overall estrogenic effect in MCF7 breast carcinoma cells. Re-analyzing expression data from multiple microarray experiments, we selected a set of key regulatory genes involved in proliferation regulation and estrogen signaling. Our quantitative real time-PCR results confirmed that the selective membrane receptor agonist, estrogen-BSA induces similarly pronounced expression changes regarding these genes as 17β-estradiol. Our light and electronmicroscopical studies revealed that the membrane-bound form of classical estrogen receptor alpha is internalized after ligand binding via dynamin dependent, caveola-mediated endocytosis. Inhibition of this internalization with dynamin inhibitor, dynasore practically abolished the regulatory effect of E2-BSA, suggesting that interaction and internalization with the scaffold protein is necessary for effective signaling.
The physiological role of plasma membrane estrogen receptor alpha is intensively studied, yet there are still several aspects of it to be resolved. The dynamin-dependent, ligand mediated internalization of mERs seems to play an important role in estrogen signaling. Our results may serve as another example how membrane initiated and nuclear receptor signaling well-orchestrated is and form an integrated system.