system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Flow Cytometry, Glioblastoma, Humans, Karyotyping, Ligands, Polymerase Chain Reaction, Receptors, Estrogen, Receptors, Progesterone, Sensitivity and Specificity, Transcription, Genetic, Transfection, Tumor Cells, Cultured.
user
Are estrogen receptors identified in the glioblastoma cell line U138MG? Context: The antiestrogen tamoxifen has been found to be effective in decreasing glioblastoma cell proliferation, but the mechanism underlying this effect and whether it is through the estrogen receptor (ER) is controversial. The objective of this study was to determine whether ERs are present in three human glioblastoma cell lines--HS683, U138MG, and JHN J889H--using the most sensitive techniques available. Ligand binding and flow cytometry were employed to identify estrogen and progesterone receptors. The reverse transcriptase-polymerase chain reaction was used to identify ER mRNA, and a novel reporter gene transfection assay demonstrated that the ER was capable of activating gene transcription. U138MG glioblastoma cells contain ERs that are capable of increasing gene transcription in response to estradiol. No ERs were found in HS683 or JHN J889H cells.
assistant
Tamoxifen may be acting through the ER in some glioblastoma cells. Final Decision: yes