In vitro viability, proliferation, and apoptosis following PLK1 downregulation using BI2536/ASO. Figure 1 shows the changes to the level of viability, proliferation, and apoptosis in each of the therapy-resistant cell lines and parental GP following PLK1 downregulation with 48 and 72 hours treatment with either ASO ((a)–(c)) or BI2536 ((d)–(f)). In case of PLK1 ASO treatment, untreated/scrambled (SCR) ASO while in BI2536 treatment, vehicle- (DMSO-) treated cells were used as control groups for comparison in these experiments. (g) Represents the efficacy of BI2536 over ASO treatment in decreasing cell viability and increasing apoptosis in therapy-resistant and parental MCL cells. (h) MTT assay showing the restoration of the viability in therapy-resistant and parental MCL cells after PLK1 reintroduction by PLK1 ASO withdrawal (ASO-WD) for 48 and 96 hours following PLK1 silencing for 48 hours. SCR ASO (Con) was used as a control in this experiment. In these experiments, the values represent the means ± SE from triplicate wells of the 96-well plates. Similar results were obtained from two sets of independent experiments. indicates the statistical difference between control MCL cells and PLK1 downregulated MCL cells.