RESUMO
The perirenal adipose tissue (PRAT), a component of visceral adipose tissue, has been recently recognized as an important factor that contributes to the maintenance of the cardiovascular system and kidney homeostasis. PRAT is a complex microenvironment consisting of a mixture of white adipocytes and dormant and active brown adipocytes, associated with predipocytes, sympathetic nerve endings, vascular structures, and different types of inflammatory cells. In this review, we summarize the current knowledge about PRAT and discuss its role as a major contributing factor in the pathogenesis of hypertension, obesity, chronic renal diseases, and involvement in tumor progression. The new perspectives of PRAT as an endocrine organ and recent knowledge regarding the possible activation of dormant brown adipocytes are nowadays considered as new areas of research in obesity, in close correlation with renal and cardiovascular pathology. Supplementary PRAT complex intervention in tumor progression may reveal new pathways involved in carcinogenesis and, implicitly, may identify additional targets for tailored cancer therapy.
RESUMO
The prognostic value of mast cells (MCs) in patients with liver metastases is a relatively new topic. The present study comparatively assessed tryptase-positive (MCT(+)) and CD117(+) MCs in liver metastases from various sites and correlated their expression with clinicopathological prognostic factors and survival. Our data pointed to differences in MCT and CD117 expression in liver metastases that seem to be related to the origin of the primary tumor. For colon cancer metastases, intra-tumor MCT(+) MCs were significantly correlated with tumor grade and nodal status, while peritumoral MCT(+) MCs and peritumoral CD117(+) MCs were significantly correlated with overall survival. No significant correlations between MCT(+) and CD117(+) MC number and clinicopathological parameters or survival were found for gastric cancer metastases. To the best of our knowledge, this is the first report regarding MC involvement in liver metastases from different malignant tumors correlated with clinicopathological parameters and overall survival. Different mast cell phenotype together with their specific correlation with tumor grade, nodal status and survival suggest their involvement in the metastatic process in a specific manner related to tumor origin. Mast cells from liver metastases remain a questionable issue regarding their origin, pathogenic role and their ability to be potential targets for adjuvant therapy.
