The protocol is performed after drug treatment on the cancer cell lines. Please provide necessary details and intricacies, as I am new to this technique.
For apoptosis, caspases are normally assayed with kits. The kits can use colorimetric or fluorescent readouts. I would recommend do this as well. This type of asay takes just a few minutes.
The proteins to look at in the western would be some of the caspase members, like 3. Maybe others can comment on which proteins and Abs to use.
Another comment, I would use complete protease inhibitor cocktail pellets if you do the lysis as described above. I personally would lyse the cells in buffer with SDS too.