Figure 2.

Phylogenetic trees from evolution species (A) and from tumors (B). (A) During evolution, changes in the genome need to be germline, meaning that all cells have the same genetic background, and this genetic is hereditary. For this purpose, those changes need to appear during fecundation or during gametogenesis. All organisms on earth share a common ancestor. Over time, the accumulation of genomic changes led to diversification in specific species. (B) Tumor initiation involves changes in the genomes. One cell gains genomic insults, resulting in the formation of tumors. Because of genomic instability, tumor cells derive in diverse clones with their own genetic changes. During tumor progression and metastasis, specific clones will survive in the new environment and under therapeutic pressure.