FN1 and neoplasm: In tumor microenvironment, paracrine or autocrine molecules participate in maintaining favorable conditions for the propagation of tumor cells, such as the extracellular matrix (ECM) component extra domain A positive fibronectin (EDA+FN), as well as the vascular endothelial growth factor A isoforms (VEGF-Axxx), the pro-oncogenic isoforms generated by the alternative splicing of FN or VEGF genes [9, 10], respectively.