Phospho-Estrogen Receptor alpha (Ser167) antibodies are essential tools for studying the post-translational modification of ERα, a nuclear hormone receptor critical in regulating gene expression linked to cell proliferation, differentiation, and survival. ERα activity is modulated by phosphorylation at specific residues, including Ser167. which lies within the receptor’s AF1 transactivation domain. Phosphorylation at Ser167 enhances ERα’s transcriptional activity, even in low-estrogen conditions, and is associated with ligand-independent activation pathways. This modification is primarily mediated by kinases such as AKT, RSK, or p90 ribosomal S6 kinase (RSK), often activated via growth factor signaling (e.g., IGF-1/EGFR pathways) or the PI3K/AKT/mTOR axis.
The phosphorylation status of Ser167 has clinical relevance, particularly in breast cancer. Elevated p-ERα (Ser167) levels correlate with resistance to endocrine therapies like tamoxifen, as persistent ERα signaling drives tumor progression. Researchers use phospho-specific antibodies to detect this modification in techniques like Western blotting, immunohistochemistry (IHC), or immunofluorescence, enabling the assessment of ERα activation states in cell lines, tissues, or patient samples. These antibodies help elucidate mechanisms of therapeutic resistance and identify patients who may benefit from combination therapies targeting both ER and kinase pathways. Additionally, p-ERα (Ser167) serves as a potential biomarker for monitoring treatment response or disease progression in hormone receptor-positive cancers.