Caspase-3/7 deficiency results in enhanced intestinal inflammation and reduced tumorigenesis.

Abstract

Aberrant intestinal epithelial cell (IEC) death is common in inflammatory bowel disease (IBD) and related animal models. While various cell death pathways contribute to disease, the dominant modalities and their regulatory mechanisms in intestinal inflammation remain ill defined. Using the DSS colitis model, we examined the contribution of apoptosis (<i>Casp3/7</i>^Δ<i>IEC</i>), necroptosis (<i>Mlkl</i>^Δ<i>IEC</i>), pyroptosis (<i>Gsdme</i>^Δ<i>IEC</i>, <i>Gsdmd^-/-)</i>, and ferroptosis (<i>Gpx4</i>^{<i>i</i>Δ<i>IEC</i>}) in IECs. Mice lacking caspase-3/7 in IECs showed worsened colitis, higher mortality, and impaired regeneration, not seen in the other transgenic mice. Caspase-3/7 deficiency in IECs hindered stem cell proliferation and increased inflammatory cell death, disrupting barrier integrity and delaying recovery. Despite heightened inflammation, <i>Casp3/7</i>^Δ<i>IEC</i> mice had reduced tumor formation in the AOM/DSS-induced colorectal cancer model. These findings highlight a protective role for caspase-3/7 in controlling inflammation and tissue regeneration, while promoting tumorigenesis following intestinal injury, and suggest modulation of caspase-3/7 as a promising therapeutic strategy in IBD and colorectal cancer.