PLK1 and neoplasm: Of note, PLK1 protein expression levels were higher in cases with somatic mutations affecting the TP53 gene (n = 24) compared to wild-type tumours (n = 80) (P= 0.0045 by Mann–Whitney test) and all samples with TP53 variants presented positive PLK1 nuclear staining compared to 80% of TP53-WT (H-score ≥1, P< 0.0001 by chi-square test, Fig. 2E).