PLK4 and cancer: The possible reasons for these are as follows: (1) KIF2A aggravates the invasion and migration of cancer cells by downregulating the polo-like kinase 4 (PLK4)/miR-129-5p axis, thus activating the PI3K/AKT/vascular endothelial growth factor signaling pathway (30, 31), leading to more frequent lymph node metastasis in BLBC patients.