ADP-ribosyl cyclase 2 (CD157)

ADP-ribosyl cyclase 2, also known as CD157 or BST1, is a glycosylphosphatidylinositol (GPI)-anchored ectoenzyme that belongs to the CD38 family [2, 6]. It functions as both a receptor and an enzyme, catalyzing the conversion of NAD+ into cyclic ADP-ribose (cADPR), which is a critical second messenger for intracellular calcium mobilization [1, 16]. CD157 is primarily expressed on cells of the myeloid lineage, such as neutrophils and monocytes, and plays a significant role in regulating cell adhesion, migration, and immune responses [2, 6]. In oncology, CD157 is frequently overexpressed in acute myeloid leukemia (AML) and epithelial ovarian cancer, where it is associated with increased tumor aggressiveness and poor prognosis [20, 21, 24]. Beyond cancer, it is implicated in the pathogenesis of rheumatoid arthritis and has been linked to Parkinson's disease through genome-wide association studies [2, 24]. Therapeutic development has focused on monoclonal antibodies, such as MEN1112 (OBT357), which aim to deplete CD157-positive cells through antibody-dependent cellular cytotoxicity (ADCC) [20, 23]. However, clinical challenges include potential safety concerns like neutropenia and liver toxicity, as well as the need for precise patient selection based on target expression levels [21].

Other names

BST1Bone marrow stromal antigen 1BST-1ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase 2CD157 antigen

Antibody-dependent cellular cytotoxicity (ADCC), inhibition of enzymatic activity (cyclase and hydrolase), and promotion of myeloid differentiation.