iHPCAL1 is a ferroptosis inhibitor that effectively inhibits RSL3-induced cell death, directly interacts with HPCAL1 and significantly inhibits HPCAL1 protein expression at 1.25-5 uM in HT-1080 and Calu-1 cells.
iHPCAL1 delayed thermal-induced HPCAL1 protein degradation in cellular thermal shift assays (CETSAs), failed to affect the phosphorylation of PRKCQ, but inhibited the phosphorylation of HPCAL1 as well as the autophagic degradation of CDH2 induced by RSL3.
The suppression of HPCAL1 phosphorylation and function induced by iHPCAL1 occurs downstream of PRKCQ phosphorylation.
Bortezomib, but not chloroquine, prevented iHPCAL1-induced HPCAL1 protein degradation, iHPCAL1 stimulates the degradation of HPCAL1 through the proteasome pathway, thereby limiting ferroptosis.
iHPCAL1 inhibited the anticancer activity of Imidazole ketone erastin (IKE) in a xenograft tumor model after inoculating HT-1080 cells into athymic nude mice or in an orthotopic pancreatic tumor model in which KPC cells, with no significant effect on IKE-induced GPX4 degradation in the xenograft tumor model.
iHPCAL1 (10 mg/kg) protects against ferroptosis-associated acute pancreatitis in mice.