Immune system in the tumor microenvironment (TME)

The immune system in the tumor microenvironment (TME) is a complex ecosystem comprising various immune cell types, including T cells, B cells, natural killer cells, and myeloid cells, which interact with tumor cells and the surrounding stroma (Binnewies et al., 2018, Nature Medicine). This environment is characterized by a dynamic balance between pro-tumorigenic inflammation and anti-tumor immunity, often skewed toward immunosuppression in advanced cancers through the recruitment of regulatory T cells and myeloid-derived suppressor cells (Anderson et al., 2017, Immunity). Therapeutic interventions, such as immune checkpoint inhibitors (e.g., anti-PD-1/PD-L1), aim to reprogram this environment to restore the cytotoxic activity of tumor-infiltrating lymphocytes (NCI, 2023). Understanding the TME is crucial for identifying biomarkers of response and overcoming resistance to immunotherapy (Pitt et al., 2016, Annals of Oncology). Consequently, while the TME is not a single molecular target, it represents the fundamental landscape where oncogenic signaling and immune evasion intersect.

Other names

Tumor immune microenvironmentTIMETumor-infiltrating immune cellsTME immune component

Drugs targeting the immune system within the TME generally work by inhibiting immune checkpoints (e.g., PD-1, CTLA-4) to restore T-cell activity, or by modulating the cytokine milieu to reduce immunosuppression (Pardoll, 2012, Nature Reviews Cancer).