endomorphin-2 has been researched along with Breast-Neoplasms* in 2 studies
2 other study(ies) available for endomorphin-2 and Breast-Neoplasms
Article | Year |
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Opioid-induced regulation of mu-opioid receptor gene expression in the MCF-7 breast cancer cell line.
The aim of the study was to investigate the presence of opioid receptor types in human breast adenocarcinoma MCF-7 cells and to characterize the changes in MOR expression induced by opioid agonist and antagonist treatment. We have shown that all three types of opioid receptors, but predominantly MOR, are expressed in MCF-7 cells. Selective MOR agonists, morphine, endomorphin-1, and endomorphin-2 downregulated MOR mRNA levels in a concentration- and time-dependent manner, but the effect produced by endomorphins was much stronger. Downregulation was blocked by the opioid antagonist naloxone. Naloxone alone produced a slight increase in MOR gene expression. Immunoblotting with antiserum against MOR-1 confirmed these results at the protein level. The results of our study indicate that, in MCF-7 cells, MOR gene expression is downregulated by opioid agonists and upregulated by opioid antagonists. We propose that the opioid-induced regulation of MOR mRNA expression is mediated by reduced binding of the transcription factors NFkappaB and AP-1 to the promoter region on the MOR gene. Topics: Analgesics, Opioid; Breast Neoplasms; Cell Line, Tumor; Gene Expression Regulation, Neoplastic; Humans; Morphine; Naloxone; Narcotic Antagonists; NF-kappa B; Oligopeptides; Receptors, Opioid, mu; RNA, Messenger; Transcription Factor AP-1; Transcription, Genetic | 2008 |
Binding of the new morphiceptin analogs to human MCF-7 breast cancer cells and their effect on growth.
In the present study, we reported on the synthesis of two new mu-opioid peptide analogs, [D-1-Nal3]morphiceptin and [D-1-Nal4]-morphiceptin [1-Nal=3-(1-naphthyl)-alanine] which expressed receptor binding affinities at least at the level of the primary opioid ligands. The new analogs also labeled mu-opioid receptors on the cells of human breast cancer MCF-7 cell line with affinity much higher than that of endomorphins and morphiceptin, the well-known mu-selective opioid peptides. However, none of the tested peptides significantly decreased cell proliferation of MCF-7 cells. Topics: Animals; Breast Neoplasms; Cell Proliferation; Convulsants; Endorphins; Humans; Ligands; Male; Oligopeptides; Protein Binding; Rats; Rats, Wistar; Receptors, Opioid, mu; Tumor Cells, Cultured | 2004 |