Brain tumor microenvironment: Mechanisms, interactions, and therapeutic opportunities

Brain tumors, including primary gliomas and metastatic brain cancers, create a complex and dynamic tumor microenvironment (TME) that significantly influences tumor progression, therapy resistance, and patient outcomes. This review explores the intricate components of the brain tumor microenvironment, including cancer cells, stromal cells, immune cells, extracellular matrix, and signaling molecules. We highlight the unique characteristics of the brain TME, such as the blood-brain barrier's role in modulating immune cell infiltration and the impact of neuroinflammation. Key interactions within the TME that promote tumor growth and resistance to conventional therapies are examined, emphasizing the crosstalk between tumor cells and the surrounding stromal and immune components. Furthermore, we discuss emerging therapeutic strategies targeting the TME, including immunotherapies, anti-angiogenic agents, and approaches to modulate the extracellular matrix. Understanding the complexities of the brain TME is crucial for developing more effective, targeted treatments and improving clinical outcomes for patients with brain tumors.