Downregulation of the long noncoding RNA EGOT correlates with malignant status and poor prognosis in breast cancer

Eosinophil granule ontogeny transcript (EGOT) is a long noncoding RNA involved in the regulation of eosinophil granule protein transcript expression. However, little is known about the role of EGOT in malignant disease. This study aimed to assess the potential role of EGOT in the pathogenesis of breast cancer. Quantitative real-time polymerase chain reaction was performed to detect the expression levels of EGOT in 250 breast cancerous tissues and 50 adjacent noncancerous tissues. The correlation of EGOT expression with clinicopathological features and prognosis was also analyzed. EGOT expression was lower in breast cancer compared with the adjacent noncancerous tissues (P < 0.001), and low levels of EGOT expression were significantly correlated with larger tumor size (P = 0.022), more lymph node metastasis (P = 0.020), and higher Ki-67 expression (P = 0.017). Moreover, patients with low levels of EGOT expression showed significantly worse prognosis for overall survival (P = 0.040), and this result was further validated in a larger cohort from a public database. Multivariate analysis suggested that low levels of EGOT were a poor independent prognostic predictor for breast cancer patients (HR = 1.857, 95 % CI = 1.032–3.340, P = 0.039). In conclusion, EGOT may play an important role in breast cancer progression and prognosis and may serve as a new potential prognostic target in breast cancer patients.

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