This combination of in vitro techniques includes the GST-pulldown assay (CARLA test), which detects interactions between ER and a coactivator; a competition binding assay that assesses ligand interactions with the receptor; a yeast-based estrogen receptor assay
(YES); and a luciferase reporter assay in cultured MCF-7 cells that reveals transcriptional activation.
four years ago and programmed to perform an estrogen receptor assay
(see photograph, page 32).
Wittliff JL, Brown AM, Fisher B: Establishment of uniformity in steroid receptor determinations for protocol B-09 of the National Surgical Adjuvant Breast Project, in Sarfaty GA, Nash AR, Keightley DD (eds): Estrogen Receptor Assays
in Breast Cancer: Laboratory Discrepancies and Quality Assurance.