To identify a human breast cancer cell line with PLK2 loss for our study, we screened the Broad Institute breast cancer cell line database and surprisingly found that the deletion of PLK2 and other nearby chromosome 5q genes was rarely observed in breast cancer cell lines in contrast to established PDX models and patient TCGA datasets (Fig. 1; Supplementary Figs. S1 and S13). The gene discussed is PLK2; the disease is breast carcinoma.