TP53 and neoplasm: Although there is so far no evidence that the participating cells can fuse entirely nor that they can create a bona fide mononuclear hybrid, the interdependent physical interferences and cytokinetic obstructions that concur with the various dividing host and/or engulfed cell-in-cell configurations are nevertheless likely to produce progeny with unstable and aneuploid tumor-promoting genomes, especially when they take place in TP53-mutated cells (Janssen and Medema, 2011; Krajcovic et al., 2011; Durgan et al., 2017; Mackay et al., 2018).