Cancer might be a failed response to renegade mitochondria

Given a hundred to a thousand mitochondria per cell, each with prokaryotic ‘naked’ DNA that is highly susceptible to muta- tion without repair (see Penta et al., 2001; Verschoor, 2013 for review), cells containing both wild type and mutant mitochondria (heteroplasmic cells, see Wallace and Chalkia, 2013 for review) may be generated every few minutes, if not every few seconds, in organisms that have more than a trillion cells.