Variable expression of podocyte‐related markers in the glomeruloid bodies in Wilms tumor

Abstract

Several podocyte-related markers are organized to express in glomerular differentiation. However, whether expression of them is virtually synchronized and a reliable indicator of the state of differentiation is unknown. The present study investigated, by immunohistochemistry, the divergent expression of several podocyte markers in the improperly differentiated glomeruloid bodies from four cases of Wilms tumors. The glomeruloid bodies were classified into immature (IGB) or mature forms (MGB) based on morphology and epithelial features. Podocytes in IGB expressed WT1, synaptopodin, podocalyxin, and nephrin, and their expression was stronger in MGB. In contrast, Pax2 was strong in IGB and diminished in MGB. p27 was first expressed in MGB. The expression pattern in each molecule mimics normal glomerulogenesis. Podocytes in MGB showed persistent expression of bcl-2 and cytokeratin with synaptopodin, podocalyxin, and nephrin by serial section, a finding unusual for normal glomerulogenesis. Moreover, parietal cells in MGB also occasionally expressed these podocyte markers. The ultrastructure revealed that podocytes in MGB showed tight junctions without foot process formations, which indicated incomplete differentiation. These results suggest that a set of podocyte differentiation markers are occasionally diversely expressed, and raise the possibility that expression of these markers is insufficient to determine the state of terminal differentiation in podocytes.

Increased Expression of Vascular Endothelial Growth Factor in Kidney Leads to Progressive Impairment of Glomerular Functions

“…In addition, we performed immunohistochemical staining using two cellular markers for human kidney, including endothelial cell markers CD31 and podocyte markers WT-1. 38 We found that two CD31 and WT-1 could cross-react with rabbit kidneys. Immunohistochemistry was performed with the Dako En-vision system following the manufacturer's instructions.…”

Primary Cell Cultures Arising from Normal Kidney and Renal Cell Carcinoma Retain the Proteomic Profile of Corresponding Tissues

“…The tumor cultures were positive to Vimentin (a characteristic marker of mesenchymal cells) as the tumor cells in the original primary tumor tissue, 22 also the normal epithelial cultured cells were positive for vimentin (not shown) but this is a characteristic of tubular cells during in vitro growth. 20,[23][24][25] In our cultures, 4-8% of cells reacted positively to Ab against a nuclear protein used as a podocyte marker, WT protein 26 (not shown), the highest value being in the cortex cultures. After staining 333 ( 21 (mean ( SD) cells were counted in each primary tumor culture and 564 ( 72 cells in each primary cortex culture, 13 ( 4 and 50 ( 27 cells, respectively, were positive for WT protein.…”

“…After staining 333 ± 21 (mean ± SD) cells were counted in each primary tumor culture and 564 ± 72 cells in each primary cortex culture, 13 ± 4 and 50 ± 27 cells, respectively, were positive for WT protein. It is worth noting that mature podocytes are vimentin positive and cytokeratin negative, , therefore, cytokeratin-negative cells contaminating our cultures may be podocytic, mesangial, or fibroblastic cells. In tumor and cortex primary cultures, the sugar residues of the brush border reacting with LCA , were evident (Figure ).…”

Transcription Factor Activity Inference in Systemic Lupus Erythematosus

“…Lupus nephritis is one of the most severe manifestations of SLE, characterized by the inflammation of the kidneys and the loss of podocytes [51]. WT1 is a well-known podocyte marker [52] and in murine model its expression is decreased [53].…”