This is just completely wrong. All cells in our body come from the same source, the same dna. That dna undergoes selection that leads to better whole-organism f

This is just completely wrong. All cells in our body come from the same source, the same dna. That dna undergoes selection that leads to better whole-organism fitness. It makes leads to cells prioritizing the common good rather than their own survival. When a cell mutates to only care about itself, goes feral you might say, that's what we call cancer.