PLK1 and neoplasm: Polo-like kinase 1 (PLK1) is a key member of the PLK familyand has important biological functions, such as bipolar arrangementof centrosomes, spindle assembly checkpoint, and cytokinesis.406−408 Targeting of PLK-1 offers novel opportunities for anticancer therapybecause of its roles in chromosome alignment and the cell cycle.409−411 The liposomes are capable of release siRNA–PLK1 and camptothecinat tumor in a sustained-release behavior.