Table 1.

Treatment and challenge of CAR-T cell therapy in the treatment of solid tumors.

Clinical challenges	Strategy	Expected outcome
Lack of specific targets [44]	Designed an antigen-specific inhibitory CAR-T molecule and a dual target CAR-T cells [48, 94]	Achieving dynamic and safe regulation of CAR-T cells [49]
CAR-T cell cannot effectively migrate and infiltrate tumor tissue [44]	Overexpression of HPSE in CAR-T cells can effectively degrade extracellular matrix and effectively infiltrate tumor tissue	Applied to solid tumor treatment [94]
Effect of tumor microenvironment on CAR-T cell therapy [44]	Specific blocking of immune checkpoint inhibition [48, 49, 94]	Improving the therapeutic effect of CAR-T cells in solid tumor [48, 94]
Tumor heterogeneity [52]	Expanding the scope of CAR-T cell therapy targeting tumor cells	Reduce tumor cells to immune response without immune response or low response to immune escape