Ontology highlight
ABSTRACT: Background
A recent epidemiological study demonstrated a reduced risk of lung cancer mortality in breast cancer patients using antiestrogens. These and other data implicate a role for estrogens in lung cancer, particularly nonsmall cell lung cancer (NSCLC). Approximately 61% of human NSCLC tumors express nuclear estrogen receptor ? (ER?); however, the role of ER? and estrogens in NSCLC is likely to be multifactorial. Here we tested the hypothesis that proteins interacting with ER? in human lung adenocarcinoma cells that respond proliferatively to estradiol (E2) are distinct from those in non-E2-responsive cells.Methods
FLAG affinity purification of FLAG-ER?-interacting proteins was used to isolate ER?-interacting proteins in whole cell extracts from E2 proliferative H1793 and non-E2-proliferative A549 lung adenocarcinoma cell lines. Following trypsin digestion, proteins were identified using liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS). Proteomic data were analyzed using Ingenuity Pathway Analysis. Select results were confirmed by coimmunoprecipitation.Results
LC-MS/MS identified 27 non-redundant ER?-interacting proteins. ER?-interacting proteins included hsp70, hsp60, vimentin, histones and calmodulin. Ingenuity Pathway Analysis of the ER?-interacting proteins revealed differences in molecular and functional networks between H1793 and A549 lung adenocarcinoma cells. Coimmunoprecipitation experiments in these and other lung adenocarcinoma cells confirmed that ER? and EGFR interact in a gender-dependent manner and in response to E2 or EGF. BRCA1 interacted with ER? in A549 cell lines and in human lung adenocarcinoma tumors, but not normal lung tissue.Conclusion
Our results identify specific differences in ER?-interacting proteins in lung adenocarcinoma cells corresponding to ligand-dependent differences in estrogenic responses.
SUBMITTER: Ivanova M
PROVIDER: S-EPMC3192725 | biostudies-literature | 2011 Sep
REPOSITORIES: biostudies-literature
Ivanova Mm M Abner Sm S Pierce Wm W Klinge Cm C
Proteome science 20110927 1
<h4>Background</h4>A recent epidemiological study demonstrated a reduced risk of lung cancer mortality in breast cancer patients using antiestrogens. These and other data implicate a role for estrogens in lung cancer, particularly nonsmall cell lung cancer (NSCLC). Approximately 61% of human NSCLC tumors express nuclear estrogen receptor β (ERβ); however, the role of ERβ and estrogens in NSCLC is likely to be multifactorial. Here we tested the hypothesis that proteins interacting with ERβ in hum ...[more]