PLK1 and cancer: Since primary tumors from various tissues express elevated levels of PLK1, and this high‐level expression frequently correlates with a poor prognosis (Wolf et al, 1997), PLK1 is a potential oncotarget for molecular cancer therapy and a prognostic marker (Yuan et al, 1997; Rodel et al, 2020; Rosenblum et al, 2020).