Expression and Clinical Significance of Programmed Death Ligand-1 and Nucleophosmin in Triple-Negative Breast Cancer

Objective: The purpose of this study was to determine the expressions of programmed death ligand-1 (PD-L1) and nucleophosmin (NPM1) in triple-negative breast cancer (TNBC) tissues, and their relevance and clinical significance. Methods: Seventy pathologically-confirmed TNBC tissue specimens were used in this study. The expressions of PD-L1 and NPM1 in TNBC tissues were determined using immunohistochemistry (streptavidin-peroxidase). The association between expressions of PD-L1 and NPM1 and clinicopathological parameters was investigated. The correlation between the two markers was analyzed using Pearson correlation coefficient, and Kaplan-Meier survival curves were generated. Results: The positive expression rates of PD-L1 and NPM1 in 70 TNBC tissue specimens were 54.29 and 51.43%, respectively. Tumor tissue differentiation was positively correlated with positive expressions of PD-L1 and NPM1 (r = 0.248,p = 0.032). Par-ticipants with PD-L1-positive, NPM1-positive, and PD-L1 and NPM1 co-positive expressions showed worse prognosis than those with negative expressions. Moreover, PD-L1-positive expression was identified as an independent risk factor for prognosis of TNBC in patients. Conclusions: PD-L1 and NPM1 may be involved in the pathogenesis of TNBC. Therefore, their expressions may be helpful for predicting the prognosis of TNBC in patients.