Necroptosis

Necroptosis is a regulated, inflammatory form of programmed cell death that is mechanistically distinct from apoptosis: rather than depending on caspase activation, it is executed through the necrosome, a signaling complex built around RIPK1/RIPK3 kinases that phosphorylates and activates the pore-forming protein MLKL, ultimately leading to plasma membrane rupture. Because it is inflammatory, necroptotic death — unlike the comparatively immunologically silent apoptosis — can further shape the surrounding immune microenvironment; necroptosis is in fact considered one of the most immunogenic forms of regulated cell death, since it efficiently supplies both tumor antigens and inflammatory alarm signals to dendritic cells, priming CD8+ T cell anti-tumor responses. In cancer, the gene encoding RIPK3 (though not RIPK1 or MLKL) is frequently silenced by promoter hypermethylation, allowing tumor cells to evade this death pathway while retaining RIPK1’s separate, pro-survival scaffolding function.