PLK1 and neoplasm: Concordant with the oncogenic conception, however, convincing evidence is accumulating that PLK1 is actively involved in the fatal events throughout tumorigenesis from the onset of oncogenic transformation, tumor growth, epithelial-mesenchymal transformation, tumor cell invasion and metastasis and, last but not least, PLK1 is supposed to participate in development of therapeutic resistance [46,146,147] and reviewed by [148].