Evaluation of podocalyxin and asprosin expressions in renal oncocytoma and frequent types of renal cell carcinoma

Renal cell carcinomas (RCC) are the neoplasm of the urogenital system with the highest mortality rate. More than 80% of renal tumors are RCCs and less than 10% are oncocytomas. The most common RCCs are clear cell RCC, papillary RCC and chromophobe RCC. Oncocytomas are the most common benign renal neoplasms. Podocalyxin (PODXL) is located mainly on the apical surface of podocytes. In addition to its physiological functions, it also plays a role in tumor development. Asprosin (ASP) is an adipokine secreted from adipose tissue. It is associated with ınsulin resistance, obesity and diabetes. Its presence has also been shown in various malignancies. In our study, we aimed to determine the expression levels of Podocalyxin and Asprosin in oncocytoma and frequents of renal cell carcinoma. 60 cases diagnosed with 15 clear cell RCC, 15 papillary RCC, 15 chromophobe RCC, 15 oncocytoma selected from our hospital archives and 15 cases in which normal kidney tissue could be evaluated from non-tumor areas were included in our study. Immunohistochemical PODXL and ASP antibodies were applied to paraffin sections. PODXL immunoreactivity was observed more in the normal kidney tissue group than in the clear cell RCC, papillary RCC, chromophobe RCC and oncocytoma groups, and a statistically significant difference was detected (p<0.001). However, no significant difference was observed between tumor groups. The highest ASP immunoreactivity between the groups was observed in oncocytomas and a statistically significant difference was detected (p <0.001). When clear cell RCC, papillary RCC, chromophobe RCC and normal kidney tissue groups were compared, higher ASP immunoreactivity was observed in normal kidney tissue tubules. A statistically significant difference was found between clear cell RCC, chromophobe RCC and normal kidney tissue tubules, and between clear cell RCC and papıllary RCC (p<0.001). ASP immunoreactivity was observed more in papillary RCC. ASP expression was seen only in tubules in normal kidney tissue. With this study, it was thought that PODXL was negatively effective for clear cell RCC, chromophobe RCC and oncocytomas, and ASP could be a useful marker in distinguishing between oncocytomas and frequent types of RCCs and in differentiating clear cell RCC from papillary RCC.