PLK1 and neoplasm: Additionally, we included an altered peptide PLK1345/9M (KGVENPLPM) to make a heteroclitic peptide vaccine, which could overcome the pre-existing immune dysfunction of cancer patients.32 PLK1345/9M revealed slower MHC-I dissociation rates in comparison to PLK1122 peptide, and PLK1345/9M vaccination could also evoke higher numbers of CD8 T-cells directed towards peptide-pulsed target but not effective against PLK1-expressing tumour cells (Fig. 1a, b).