PLK1 and malignant colon neoplasm: While the same treatment (48 h, 100 nM BI6727) of CIN+ SW480 cells increased the mean number of chromosomes from 50.54 ± 3.73 to 61.09 ± 2.89 at day 12 following treatment, in APC-ΔC-expressing cells a rise from 61.23 ± 5.55 to 84.95 ± 7.24 was determined (Supplementary Fig. 5b, c) suggesting that both treatments (1) expression of APC-ΔC and (2) PLK1 inhibition contribute to promote chromosomal abnormalities in colon cancer cells with different degrees of chromosomal instability.