PLK1 and breast cancer: The Cancer Genome Atlas (TCGA) data show that PLK1 is overexpressed in more than 20 human cancers, and high expression levels of PLK1 are closely associated with aggressive tumor phenotypes, worse treatment response, and poor prognosis in colorectal cancer, bladder cancer, lung adenocarcinoma, and breast cancer (Liu et al., 2017; Guerrero-Zotano et al., 2023; Zhang et al., 2022).