There are biological mechanisms that attempt to stop this process; signals are given to inappropriately dividing cells that should trigger cell death, but sometimes additional mutations occur that cause cells to ignore these messages.
Postoje biološki mehanizmi koji pokušavaju zaustaviti ovaj proces; netočno podijeljenim stanicama šalju se signali koji bi trebali izazvati smrt stanice, ali ponekada se dese mutacije koje izazivaju ignoriranje ove poruke.