Employing microparticles loading metformin, Wei et al. showed their efficacy in repolarizing M2-like TAMs to into M1-like phenotype and remodeling TME by increasing the recruitment of CD8+ T cells into tumor tissues and decreasing immunosuppressive infiltration of myeloid-derived suppressor cells and regulatory T cells (Wei et al., 2021). Here, CD8A is linked to neoplasm.