In the tumor bed, stem-like exhausted CTLs, which were defined as PD-1+Slamf6+Tim3−, expressed higher IL-17A receptor heterodimers and lower leukocyte function-associated antigen-1 (LFA-1) than terminally exhausted CTLs did, that were defined as PD-1+Slamf6−Tim3+. The gene discussed is SLAMF6; the disease is neoplasm.