MicroRNA-17, microRNA-18a, and microRNA-19a are prognostic indicators in esophageal squamous cell carcinoma.

BACKGROUND: The members of the microRNA (miR)-17-92 cluster have been reported to be highly expressed in several cancers. However, whether their expression is associated with clinicopathologic factors, the prognosis of patients in esophageal squamous cell carcinoma (ESCC) remains unknown.

METHODS: Using SYBR green real-time quantitative reverse transcription polymerase chain reaction, we detected the expression of members of the miR-17-92 cluster, including miR-17, miR-18a, miR-19a, miR-20a, miR-19b, and miR-92a, in 105 surgical specimens from ESCC patients. We then investigated their impact on clinicopathologic factors and survival.

RESULTS: All six members of the miR-17-92 cluster had a significantly higher level of expression in the 105 ESCC tissue specimens than in normal esophageal mucosa (p < 0.05). The miR-18a expression positively correlated with tumor stage (p = 0.025). Meanwhile, miR-92a expression positively correlated with clinical stage (p = 0.022), and miR-19b expression positively correlated with tumor size (p = 0.005), lymph node metastasis (p = 0.040), and clinical stage (p = 0.011). The overexpression of miR-17a was correlated positively with lymph node metastasis (p = 0.035) and clinical stage (p = 0.022). MiR-18a, miR-17, and miR-19a were prognostic indicators for progression-free survival and overall survival. both in univariate analysis and in multivariate analysis.

CONCLUSIONS: This study suggests that miR-17, miR-18a, and miR-19a can serve as potential unfavorable prognostic biomarkers in ESCC which are associated with some clinicopathologic factors. However, the regulatory pathway associated with potential candidate miRNAs remains to be explored.