Expression and prognostic utility of SSX2IP in patients with nasopharyngeal carcinoma

Cell adhesion affects carcinogenesis, tumor progression, and metastasis. We datamined a published transcriptome (GSE12452) of nasopharyngeal carcinoma (NPC) and identified SSX2IP as a significantly upregulated gene in NPC carcinogenesis among genes associated with cell adhesion (GO:0007155). Consequently, we assessed SSX2IP protein expression and its prognostic significance in 124 patients with NPC using immunohistochemistry and the H-score method. The status of SSX2IP immunoexpression correlated with clinical and pathological characteristics, as well as oncological outcomes. High levels of SSX2IP expression were significantly associated with more advanced primary tumor and TNM stages. Kaplan-Meier and log-rank analyses revealed that high levels of SSX2IP expression, and advanced tumor stage and lymph node metastasis were significantly associated with lower rates of local recurrence-free survival (LRFS), distant metastasis-free survival (DMeFS), and disease-specific (DSS) survival. Multivariate analysis showed that high levels of SSX2IP expression significantly predicted DSS (hazard ratio [HR], 4.290; 95% confidence interval [CI], 2.271-8.102; p < 0.001), DMeFS (HR, 4.159' 95% CI, 2.072-8.345; p < 0.001), and LRFS (HR, 3.007' 95% CI,: 1.418-6.378; p = 0.004). We associated high levels of SSX2IP immunoexpression with aggressive pathological features and worse oncological outcomes, suggesting its potential therapeutic value for patients with NPC.