Many studies have tried to delineate the precise and proper regulatory mechanisms of PLK-1 in mitosis, specially during the spindle pole maturation (SPM), metaphase-anaphase transition, chromosome segregation, cytokinesis, and spindle assembly checkpoint (SAC), because deregulation of these key events during mitosis are responsible for the onset of tumorigenesis as well as the poor prognosis of cancer [3, 8–12]. This evidence concerns the gene PLK1 and cancer.