Background: Apoptotic nuclear morphology can occur independently of DFF40/CAD-mediated DNA fragmentation. Results: DFF40/CAD induces 3Ј-OH single-strand DNA nicks/breaks and nuclear collapse during caspase-dependent apoptosis. Conclusion: Caspase-dependent apoptotic nuclear collapse is prompted by DFF40/CAD-mediated single-strand DNA damage. Significance: The knowledge of how apoptotic nuclear collapse occurs should be relevant to understand the final steps of cell demise and its influence on the cellular environment.

Background: Apoptotic oligonucleosomal DNA degradation is mediated by DFF40/CAD endonuclease. Results: Poor DFF40/CAD expression in the cytosol coupled to the caspase-dependent cytosolic processing of ICAD L/S impair oligonucleosomal DNA degradation in SK-N-AS cells. Conclusion: Oligonucleosomal DNA fragmentation during apoptosis is directly correlated with adequate DFF40/CAD cytosolic levels. Significance: Learning how DFF40/CAD works is crucial for understanding the relevance of apoptosis ending in cancer development.

Background: DFF40/CAD mediates nuclear fragmentation and oligonucleosomal DNA degradation during apoptosis. Results: DFF40/CAD overexpression allows apoptotic-defective LN-18 cells to display internucleosomal DNA degradation but not chromatin disassembly upon cytotoxic insult. Conclusion: DFF40/CAD can induce DNA laddering in the absence of apoptotic chromatin disassembly. Significance: Dissecting DFF40/CAD regulation may shed light on some of the apparent non-desirable tumor responses in currently used anti-cancer therapies.

Background: Caspase activation triggers apoptotic cell death. Results: Chelerythrine triggers necrotic-like cell death by an early and pronounced activation of caspases. Conclusion:The rate and level of caspase activation dictate whether cells die displaying apoptotic or necrotic features. Significance: Most antitumor drugs prompt concomitant apoptotic and necrotic morphological deaths; therefore understanding how the apoptosis-necrosis continuum occurs should shed light on anticancer treatment efficacy.