ABSTRACT
One of the most recognizable features of a tumoral cell is the disproportionate growth that is intimately related to tumor aggressiveness and invasiveness. As a consequence of this growth, the number of blood vessels supporting the tumor rises exponentially to fulfill the exacerbated need of nutrients and oxygen. Therefore, and attending to histopathological analyses it is not uncommon to find necrotic regions inside the tumoral core, which is densely populated, in highly proliferative tumoral phenotypes. In order to alleviate this deficiency, tumoral cells elicit the formation of neovessels by stimulating neoangiogenesis. This angiogenic process is tightly regulated and results in the participation of several transcription factors, being HIF-1α one of the most important. This factor exerts its transcriptional activity on several target genes that intervene in crucial processes for the tumoral phenotype such as glycolysis, apoptosis and metastasis (Bárdos et al, 2004),making it a good marker of tumoral aggressiveness and invasion capacity in several types of tumors (Evans et al, 2004; Victor et al, 2006; Gordan et al, 2007; Furlan et al, 2007).
