GSDMD

[6] It belongs to the gasdermin family which is conserved among vertebrates and comprises six members in humans, GSDMA, GSDMB, GSDMC, GSDMD, GSDME (DFNA5) and DFNB59 (Pejvakin).

[13] Caspase-1, conserved in vertebrates, is involved in the canonical pathway and is activated by canonical inflammasomes such as NLRP3 and NLRC4 inflammasomes, which are multi-protein complexes that are formed upon recognition of specific inflammatory ligands called pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) in the cytosol by NOD-like receptors (NLRs).

[11] Caspase-11 in mice and its human homolog caspase-4 and -5 are involved in the non-canonical pathway and are activated by directly binding cytosolic lipopolysaccharide (LPS) secreted by gram-negative bacteria.

Hence, failure to express or cleave GSDMD can block pyroptosis and disrupt the secretion of IL-1β, and eventually unable to ablate the replicative niche of intracellular bacteria.

Mutation of GSDMD is associated with various genetic diseases and human cancers, including brain, breast, lung, urinary bladder, cervical, skin, oral cavity, pharynx, colon, liver, cecum, stomach, pancreatic, prostate, oesophageal, head and neck, hematologic, thyroid and uterine cancers.

[17] Recently, studies have revealed that downregulation of GSDMD promotes gastric cancer proliferation due to the failure to inactivate ERK 1/2, STAT3 and PI3K/AKT pathways, which are involved in cell survival and tumour progression.

[20] The critical role of GSDMD in pore formation during pyroptosis provides a new avenue for future drug development for treating inflammatory caspase-associated auto-inflammatory conditions, sepsis and septic shock.

Structure of GSDMD C-terminal domain
Overview of GSDMD activation and pore-forming mechanism