The role of SPP1+TAMs in cancer: Impact on patient prognosis and future therapeutic targets

Tumor-associated macrophages (TAMs) are a critical population of immune cells that infiltrate the tumor microenvironment (TME) and significantly influence cancer progression, prognosis, and treatment. SPP1⁺TAMs represent a tumor-promoting subset of TAMs characterized by their ability to secrete osteopontin, along with various cytokines and chemokines, and to interact with a diverse array of ligands. Within the tumor microenvironment, SPP1⁺TAMs are primarily localized to hypoxic and necrotic regions, as well as along the tumor margins. Studies have shown that SPP1⁺TAMs promote tumor angiogenesis, invasion, metastasis, and immunosuppression. The infiltration of SPP1⁺TAMs has been associated with poor prognosis in cancer patients. Furthermore, their presence may influence disease progression and treatment response. Targeting SPP1⁺TAMs has the potential to reduce immunosuppression and augment immunotherapeutic efficacy, thereby contributing to improved treatment outcomes.