However, despite being similar, it is still necessary to elucidate the mechanisms and pathways involved in the regulation of angiogenic factors in canine PC samples [170], considering that some transcriptional factors, such as EGR1 [174] and FOXA1 [175], as well as the overexpression of genes involved in tumor suppression, such as MDM2 [176], have been identified as important direct or indirect regulators of angiogenesis in human PC. This evidence concerns the gene EGR1 and pachyonychia congenita.