None of them fulfill all of the requirements for an ideal antigen, but potential leukemia-specific antigens are those derived from alternative mRNA splicing, such as CD44v6, or molecules that are upregulated or subcellularly re-located upon cellular stress (PR1 peptide, GRP78) or chemical induction (CD38, FRβ) [56]. The gene discussed is FOLR2; the disease is leukemia.