Emopamil-binding protein-related protein (EBRP) (EBRP)

Emopamil-binding protein-related protein (EBRP), also known as SR31747A-binding protein 2 (SRBP2), is a 206-amino acid integral membrane protein localized to the endoplasmic reticulum and nuclear envelope [1, 3]. It was identified as a high-affinity binding site for the experimental sigma ligand SR31747A, which exhibits potent immunosuppressive and antiproliferative activities in various cancer models [1, 2]. Although EBRP shares approximately 41-43% sequence identity with the human sterol isomerase (HSI/EBP), it lacks detectable steroid isomerase activity, suggesting it serves a distinct regulatory or structural function within the cell [1, 3]. In clinical research, EBRP is highly expressed in breast and prostate cancer cell lines, and its expression levels in patient biopsies have been proposed as a significant prognostic marker for disease-free survival [1, 2]. The protein also binds the selective estrogen receptor modulator tamoxifen with high affinity, which may contribute to the complex pharmacological effects of tamoxifen in oncology [1]. As a member of the SR31747A-binding protein family, EBRP represents a specialized therapeutic target for the development of novel antineoplastic and immunomodulatory agents [5, 6].

Other names

SR31747A-binding protein 2SRBP2SRBP-2EBP-related protein

Binding of sigma ligands such as SR31747A to EBRP mediates antiproliferative and immunosuppressive effects, potentially through the modulation of sterol-related signaling pathways or nuclear membrane-associated regulatory processes.