Upregulation of the long non-coding RNA SPRY4-IT1 predicts poor prognosis in breast cancer

Background: The upregulation of long non-coding RNA SPRY4 intronic transcript 1 (lncRNA SPRY4-IT1) has been observed in breast cancer (BC). However, there is no previous study of the relationship between SPRY4-IT1 and patient prognosis in BC. This study investigated the prognostic value of SPRY4-IT1 in BC patients. Methods: The relative expression levels of SPRY4-IT1 were detected by RT-qPCR in 102 paired BC tissues and adjacent non-cancerous tissues. The association of SPRY4-IT1 expression with clinicopathological features and prognosis was statistically analyzed. Results: The findings revealed that the SPRY4-IT1 expression was significantly upregulated in clinical BC tissues compared to adjacent normal tissues (P < 0.001). Furthermore, the SPRY4-IT1 level was significantly associated with tumor size (P = 0.009), TNM stage (P = 0.0008) and lymph node metastasis (P = 0.01). Using a Kaplan-Meier analysis, it was shown that patients with high SPRY4-IT1 expression had a significantly poor overall survival (OS) rate (P = 0.0056) and a disease-free survival (DFS) rate (P = 0.0001). Moreover, multivariate Cox analysis revealed that SPRY4-IT1 expression was an independent poor prognostic factor for both OS (P = 0.024) and DFS (P = 0.025) in BC patients. Conclusions: SPRY4-IT1 expression is an independent prognostic factor for patients with BC and may serve as a potential biomarker to predict prognosis in BC patients.