HOXB8 and neoplasm: Twelve is the number of clusters which group together the different dynamics of gene expression in the different conditions, by categories which seemed to us to be the most interesting (i.e., which allow bringing out potential oncogenes, potential tumor suppressors, as well as genes not implicated in the tumor suppressor role of HOXB8 by not being reversed by HOXB8 in the MEK1ca condition).