Piezo1 as a mechanical checkpoint in T cell immunotherapy for solid tumors.

T cell-based immunotherapies exhibit limited efficacy against solid tumors, a challenge primarily attributed to the immunosuppressive and mechanically hostile tumor microenvironment (TME). Within this context, the mechanosensitive ion channel Piezo1 has emerged as a key TME mechanosensor, yet its role in modulating T cell-mediated anti-tumor immunity remains to be fully elucidated. This review aims to synthesize existing evidence on Piezo1's regulation of T cell functions, including activation, proliferation, and infiltration, and its broader impact on immunotherapy for solid tumors. We highlight Piezo1's dual regulatory function in the immune landscape: acute activation robustly enhances T cell effector functions and cytotoxicity, whereas chronic stimulation within the stiff TME paradoxically promotes T cell exhaustion. Importantly, preclinical studies demonstrate that modulating Piezo1 signaling, particularly in combination with matrix normalization synergistically enhances the infiltration, persistence, and overall antitumor efficacy of adoptive T cells and endogenous immune responses. These findings position Piezo1 as a promising mechanical checkpoint for improving T cell therapies. Nevertheless, significant challenges persist for clinical implementation, including the heterogeneity of mechanical signals and the pleiotropic nature of Piezo1 across different cell types. Future research should therefore focus on developing T cell-specific mechanotherapies, identifying novel targets, and validating mechanical biomarkers to guide patient stratification, thereby accelerating the clinical translation of "mechanoimmunology".