CASP3 and neoplasm: Additional evidence for the TRAIL-Birinapant combined treatment efficiency in HT29 cells was provided by light microscopy images, showing detached HT29 cells after 48 or 72 h TRAIL-Birinapant combined treatments (Fig. 5c, left or right panel respectively), while confocal microscopy images indicated the fragmented (apoptotic) nuclei and cleaved caspase-3 distribution in a number of treated tumour cells (Fig. 5d).