Figure 3. Niclosamide and CPT induce protein ubiquitination respectively and synergistically enhance caspase-3 and PARP cleavage.

The cell lysates were prepared from U87 cells treated with either 5 μM niclosamide (Nicl), or 5 μM CPT alone, or with combined treatment for 24 hours and resolved by SDS-PAGE and then immunoblotted with antibodies specific for ubiquitin, cleaved PARP, and cleaved caspase-3 (A). β-Actin was used as the loading control. The protein levels from Western blot were quantified by densitometry. (B) Ubiquitinated proteins. (C) Cleaved PARP and cleaved caspase-3. Data represent the mean ± S.E.M. ^* p < 0.05; ^*** p < 0.001.