Peroxidasin expression is increased in intratumoural capillaries and in proximal tubular cells adjacent to clear cell renal cell carcinoma.

Abstract

Peroxidasin (PXDN), is a heme peroxidase with a critical role in the crosslinking of type IV collagen, being essential for basement membrane integrity. In many cancers, PXDN overexpression has been linked with processes associated with poor disease outcomes, namely the impairment of endothelial functions, pathogenesis of vascular diseases, vascular remodelling, apoptosis, and tissue fibrosis. In RCC, almost nothing is so far known. In this work we characterized the expression of PXDN in tumour and non-neoplastic adjacent tissue from clear cell renal cell carcinoma (ccRCC) and renal oncocytoma by immunohistochemistry. Results showed a significant increase of PXDN expression in intratumoural capillaries of ccRCC in comparison with oncocytoma, and an increase in the proximal tubular epithelial cells of non-neoplastic adjacent parenchyma from ccRCC cases, in comparison with the same area from oncocytomas. Overall, our results suggest, for the first time, that PXDN may have a role in tumour angiogenesis that may favour metastases and tumour malignity, being also enrolled in the crosstalk between the tumour and adjacent tissue, that deserves further investigation. HighlightsO_LIPeroxidasin is increased in ccRCC microvasculature comparing to oncocytoma. C_LIO_LIPeroxidasin is increased in proximal tubules of ccRCC kidney adjacent parenchyma. C_LIO_LIIs Peroxidasin a modulator of tumour microenvironment promoting angiogenesis? C_LI