PRF1 and cancer: A recent research article published in Science by Ritter et al. reported that endosomal sorting complexes required for transport (ESCRT) proteins mediate repair of lesions in the cell membrane caused by the pore-forming toxin perforin at sites of cytotoxic T cell engagement.1 Subsequent entry of granzymes and initiation of apoptosis of cancer cells is thus limited, leading to reduced sensitivity against T cell‐mediated cytotoxicity.1 Along these lines, this could constitute a new critical resistance mechanism for T cell-based treatment approaches.