A GRIK2 peptide-specific cytotoxic T lymphocyte (CTL) clone was able to recognize GRIK2-overexpressing UM-UC-3 cells and ALDH-high clone cells, suggesting that GRIK2 peptides could serve as novel immunotherapeutic targets for bladder cancer CSCs/CICs. The gene discussed is GRIK2; the disease is urinary bladder cancer.