Prostaglandin F2 receptor negative regulator (PTGFRN) (PTGFRN)

Prostaglandin F2 receptor negative regulator (PTGFRN), also known as CD315 or Cancer cell surface protein-1 (CSP-1), is a type I transmembrane glycoprotein belonging to the EWI family of tetraspanin-associated proteins [UniProt Q9P2B2, Marquez et al., 2019]. It was initially identified as a regulator of the prostaglandin F2-alpha receptor but has since been recognized as a significant player in cancer progression and metastasis [UniProt Q9P2B2, Marquez et al., 2021]. PTGFRN is overexpressed on the surface of various malignant cells, including mesothelioma, head and neck squamous cell carcinoma, and medulloblastoma, while showing minimal expression in healthy tissues [Marquez et al., 2019, Marquez et al., 2024]. Its biological role involves modulating cell-cell adhesion and signaling through its interaction with tetraspanins like CD9 and CD81 [UniProt Q9P2B2]. Due to its high expression in tumors and its ability to undergo rapid internalization upon antibody binding, PTGFRN has emerged as a promising target for antibody-drug conjugates (ADCs) [Marquez et al., 2019]. Experimental ADCs such as AG02-saporin and 8C7-duocarmycin have demonstrated potent anti-tumor activity in preclinical models by delivering cytotoxic payloads directly into PTGFRN-expressing cancer cells [Marquez et al., 2019, Marquez et al., 2024]. The protein is also associated with the maintenance of a stem cell-like phenotype in cancer cells, further contributing to its role in tumor recurrence and resistance [Marquez et al., 2021]. Consequently, PTGFRN represents a novel therapeutic target for aggressive and metastatic cancers with high unmet medical needs [Marquez et al., 2024].

Other names

Cancer cell surface protein-1CSP-1CD315FPRPEWI-FProstaglandin F2-alpha receptor-associated proteinGlu-Trp-Ile family member F

Antibody-drug conjugate (ADC) internalization and delivery of cytotoxic payloads; Inhibition of tumor growth and metastasis via targeted cell death [Marquez et al., 2019; Marquez et al., 2024].