Class I homeobox genes (HOX), are 39 transcription factors involved in the regulation of different cell processes: i) cell identity; ii) cell growth and proliferation; iii) cell communication; iv) determining anteroposterior axis during embryonic development; these genes are characterized by 183 nucleotide sequence (homeobox) encoding for a 61 amino acid domain (hoemodomain).
HOX network controls the cell memory program during cell differentiation and is related to neoplastic transformation. Three gene families regulate the cell memory program: the Polycomb genes, able to block DNA-chromatin interaction leading to HOX genes silencing; the Trithorax genes, able to induce an open configuration of DNA-chromatin interaction and leading to HOX genes activation. Finally the HOX genes involved in the orchestration of the cell phenotype through the fine regulation of specific gene program.
The proposal of this review, considering the recent literature and my personal research, is clarify the involvement Class I homeobox genes in the control of neoplastic transformation.
Key Words : HOX, Cancer, Cell Memory Program, Solid Tumors