Live anchorage-dependent PDAC microtumours catch dead-cell debris and display the death phenotype. (a,b) Morphology of anchorage-dependent PCI-55 microtumours. Comparison with the morphology of a single cell (a). PCI-55 microtumour forming huge lamellipoedia (b,c). Time-lapse images of PCI-55 microtumours moving to catch debris in culture medium. Time shown as hh:mm (See Supplementary Movie 7). (d,e) Time-lapse images of live and dead cell assays. Live PCI-55 microtumours that had self-organised on the micro/nanoplate for 1 day were further cultured with medium containing Annexin V Alexa Fluor 488 and EthD-1. Live PCI-55 microtumours stretching to catch external floating apoptotic cells and dead-cell debris, using huge lamellipoedia (d) (See Supplementary Movie 8). PCI-55 microtumours massively accumulated Annexin V on their surfaces (e,f). Time-lapse images of a PCI-55 microtumour anchored to the micro/nanoplate. PCI-55 cells in the mitotic phase were covered by the strong green fluorescence of annexin V. (g) Visualisation of the sucking force of PCI-55 microtumours anchored to the micro/nanoplate. PCI-55 microtumours were cultured with medium containing Alexa488-conjugated nanobeads. A large deviation in the deposition of the nanobeads was observed around PCI-55 microtumours, which indicates a strong suction force on the surface of live PDAC microtumours (See Supplementary Movie 9). (h) Time-lapse images of PCI-55 microtumours cultured back in a culture dish. They stopped elongating and started to remove accumulated PS from their surfaces (see Supplementary Movie 10). (i,j) Cocultured CFSE-labelled NK cells do not attack PCI-55 microtumours anchored to the micro/nanoplate. Time-lapse images (i) (see Supplementary Movie 11). Red fluorescence; EthD-1. Time shown as hh:mm. There was an increase in dead NK cells in the coculture, but they were not from PCI-55 microtumours (j).