Fig. 3.

The homoharringtonine/bortezomib regimen induces caspase activation and alters the NOXA/MCL1 ratio. a, b OCI-LY18, Carnaval, HBL1 and NCEB cells were treated with HHT (10 to 20 nM) alone or with bortezomib (2 to 3 nmol/L) for 24 h after which cells were lysed and proteins extracted. Expression of the indicated proteins was determined by Western blotting using the indicated antibodies. Each lane was loaded with 25 μg of protein; blots were stripped and re-probed with tubulin/actin to ensure equivalent loading and transfer. Results are representative of three replicate experiments. c SU-DHL-4 cells were exposed the HHT (25 nmol/L) and bortezomib (4 nmol/L) individually or together for 24 h after which cells were lysed and subjected to immunoprecipitation using BAK or NOXA Abs. The immunoprecipitates were separated by SDS-PAGE and immunoblotted with MCL-1 (left and right panel)