Discovery and characterization of actionable tumor antigens

Table 1 Classes of tumor antigens

	TAAs	mTSAs	aeTSAs
Genomic origin	Exonic ++++	Exonic++ Non-exonic ++	Exonic + (some CGAs) Non-exonic ++++
Expression in mTECs/normal tissues	Yes	No	No
Mutation	No	Yes	No
Shared among tumors	Often	No/rarely	Often
Derivation	Overexpression due to genetic and epigenetic changes	Somatic mutations	Epigenetic changes Aberrant splicing

The relative frequency of exonic vs non-exonic antigens is indicated using a scale of + (rare) to ++++ (very common) for each class of tumor antigens. aeTSA, Aberrantly expressed tumor-specific antigen; CGA Cancer-germline antigen, mTEC Medullary thymic cell, mTSA Mutated tumor-specific antigen, TAA Tumor-associated antigen