PTTG1 and cancer: This could potentially explain the observed worse patients’ disease-free survival and more advanced cancers (higher grade) in the group of patients with high levels in comparison to patients with low levels of PTTG1. However, negative enrichment of genes connected with the G2M checkpoint was observed by us in the case of patients with low expression levels of PTTG2. The G2M checkpoint is a particularly important cell cycle checkpoint because it ensures that cells do not initiate mitosis until the damaged or incompletely replicated DNA is fully repaired.