CASP3 and cancer: As a future study, it will be interesting to reveal how procaspase-3, the inactive precursor zymogen of caspase-3, may function as a regulator of caspase-3 activity in HT-29 cells exposed to intact ATP and wheat phytase-treated ATP, even though the relationship between overexpression of procaspase-3 and insufficient caspase-3 activity is puzzling in various cancer cell lines until now [35], and the mechanism by which procaspase-3 is converted into active caspase-3 remains unclear [36].