PLK1 and cervical squamous cell carcinoma: Kaplan–Meier survival curves for event-free survival of 285 all types of cervical cancer patients (233 CESC patients and 52 cervical adenocarcinoma patients) from TCGA database indicated that the event-free survival rate of cervical cancer patients with higher expression of PLK1 was shorter than that of patients with lower PLK1 (HR = 2.020, P = 0.0197) (Fig. 7C).