MOSPD1, Motile Sperm Domain-Containing Protein 1, is a gene coding for a small protein. It is part of a gene family with Mospd2 and Mospd3, characterized by a major sperm protein domain and two transmembrane domains. MOSPD1 localizes to the endoplasmic reticulum, Golgi apparatus, and can translocate to the nucleus. It is involved in mesenchymal-epithelial cell transition, fatty acid metabolism, and may regulate the Wnt/β -catenin signaling pathway. Gene knockout models could potentially help in further understanding its function [2,3,5].

In breast cancer, MOSPD1 expression is higher compared to normal tissues, correlating with poor clinical outcomes. Its suppression inhibits tumor growth, while overexpression accelerates it. Silencing MOSPD1 also enhances sensitivity to anti-PD-L1 therapy [1]. In gastric cancer, MOSPD1 knockdown decreases cell proliferation, migration, invasion, and tumor growth, and it affects fatty acid metabolism-related enzyme levels and the MAPK pathway [3]. MOSPD1-null embryonic stem cells have deficiencies in differentiating into multiple cell lineages, and the growth rate of MOSPD1-null mesenchymal stem-like cells is impaired [4].

In summary, MOSPD1 plays a significant role in cell differentiation, proliferation, and cancer progression. Findings from gene-knockout models in stem cells and in vivo cancer models highlight its importance in breast and gastric cancer, suggesting it could be a potential therapeutic target in these diseases.