Leukocyte Subset Dynamics in the Tumor Microenvironment: Dual Roles, Single-Cell Insights, and Implications for Cancer Immunotherapy in Nigeria
DOI:
https://doi.org/10.64229/qevcth55Keywords:
Tumor Microenvironment, Leukocyte Subsets, Cancer Immunotherapy, Single-Cell Analysis, Immune Suppression, Nk Cells, Regulatory T CellsAbstract
The tumor microenvironment (TME) constitutes a highly complex and dynamic ecosystem wherein diverse leukocyte subsets engage in intricate cross-talk that ultimately dictates the balance between tumor progression and suppression. This review provides a comprehensive analysis of the dualistic functions of key immune cell populations-including natural killer (NK) cells, effector T cells, regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs), and tumor-associated macrophages (TAMs)-within this milieu. Particular emphasis is placed on the Nigerian context, where unique genetic backgrounds, such as the high prevalence of sickle cell trait, and environmental factors, including endemic infections, significantly shape immune phenotypes and cancer pathogenesis. We explore how cutting-edge single-cell technologies are revolutionizing our understanding of the spatial architecture, functional plasticity, and cellular heterogeneity of these leukocytes in patient cohorts, revealing mechanisms of both immune surveillance and tumor-promoting immunosuppression. The paradoxical roles of these cells elucidate the variable clinical outcomes observed with immunotherapies and underscore the critical need for precision medicine strategies that are tailored to individual immune landscapes. Finally, we discuss emerging therapeutic modalities aimed at selectively depleting pro-tumor subsets like Tregs or MDSCs while activating anti-tumor effectors such as NK cells, which hold substantial promise for reshaping the TME and improving oncology outcomes both in Nigeria and across the globe.
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Copyright (c) 2025 Okluchi Hartumu (Author)
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