The expression of redox proteins in phyllodes tumor

This study aimed to investigate the associations between the expression of redox-related proteins which regulate reactive oxygen species (ROS) production and the histologic factors in phyllodes tumor (PT). We used tissue microarrays to analyze 193 PTs and performed immunohistochemical staining against five redox-related proteins including catalase, thioredoxin reductase (TxNR), glutathione S-transferase π (GST π), thioredoxin interacting protein (TxNIP), and manganese superoxide dismutase (MnSOD). We then compared the immunohistochemical results and histologic parameters. The 193 PTs were classified as benign (n = 145, 75.1 %), borderline (n = 33, 17.1 %), and malignant (n = 15, 7.8 %). With worsening histologic grade, the expression of catalase, TxNR, TxNIP, and MnSOD in the stromal component increased (P < 0.001), and GST π and MnSOD expression in the epithelial component increased (P = 0.014, and 0.038). Significant associations were found between the expression of catalse-TxNR, catalase-TxNIP, catalase-MnSOD, TxNR-TxNIP, TxNR-MnSOD, and TxNIP-MnSOD in both the epithelial and stromal components (P < 0.05). This study confirmed that the stromal expression of catalase, TxNR, TxNIP, and MnSOD increased with worsening histologic grade in PT, reflecting the change in ROS production during the malignant transformation of PT.