The aim of the “Pasteur International Cancer Conference 2023” is to share the latest findings and new concepts in cancer biology, with major implications in our understanding of cancer etiology, onset, evolution, and therapy resistance. The four sessions will cover i) cancer cell plasticity, genetics and epigenetics; ii) competition, heterogeneity and clonality of cancer cells; iii) motility, biomechanics and biophysics of cancer cells; iv) tumor environment – immune cells, neural cells and microbiome.