TP53 and skin neoplasm: The aims of this study are: 1) to analyze the immunohistochemical expression of p53 and phospho-p53 Serine392 in canine endothelial tumours that are located in the skin; and 2) to determine if any correlation exists between p53 and phospho-p53 Serine392 overexpression and cell proliferation in skin tumours.