but when this happens in real life, it looks like mass shootings

i.e., I'm saying (due to how I think) that in the layer of the cells, like the biological cells that come together to form one human, a T cell activates itself to fight tumors (damaged tissues? organism mistakes?)...

is somehow comparable to a human person snaps, "goes postal", or things like this. (keep in mind that some places are truly deep within the 'cancer tissue'; and yea, this whole comment implies viewpoint that 'civilization is cancer' or something like that)

I've seen some movies that could be like this too, like "sleeper agent gets activated" trope, or other kinds of anamnesis-processes making people suddenly act far from the norms