Table 1.

Rationales of each combination therapy

Treatments	Rationales	Concerns
Checkpoint inhibitor plus cytotoxic agents	Enhance cellular immunity	Efficacy may be influenced by timing when cytotoxic agents add
	Augment dendritic cell maturation	Severe myelosupression may interrupt immune checkpoint therapy
	Reduce MDSC and Tregs
	Decreases CAF
Combination with checkpoint inhibitors	Activate tumor immunity by different mannar	ir AE will increase
	Provide synergy efficacy even in immune resistant tumor
Checkpoint inhibitor plus T cells stimulate agents	Activate tumor immunity by different mannar	Severe AE including cytokine storm may occur
	Deactive Tregs
Checkpoint inhibitor plus cancer vaccine	Increase the presentation of taas
	Enhance PD-L1 expression
Radiotherapy	Enhance cross priming of ctls	Optimal schedule and dose are not established
	Enhanse abscopal effect

MDSC: Myeloid-driven suppressor cell; CAF: Cancer-associated fibroblast; Tregs: Regulatory T cells.