Expression and clinicopathological significance of miR-193a-3p and its potential target astrocyte elevated gene-1 in non-small lung cancer tissues

Cancer Cell Int. 2015 Aug 7:15:80. doi: 10.1186/s12935-015-0227-8. eCollection 2015.

Abstract

Background: Aberrant expression of miR-193a-3p and astrocyte elevated gene-1 (AEG-1) have been revealed to be related to the tumorigenesis of various cancers, including non-small cell lung cancer (NSCLC). However, the significance of miR-193a-3p and its correlation with AEG-1 in NSCLC has not been explored. The purpose of this study was to evaluate the association between miR-193a-3p and AEG-1 and their relationship with the clinicopathological features in NSCLC patients.

Methods: Via online in silico prediction, complementary sequences were found between miR-193a-3p and the 3'-untranslated region of AEG-1. Three independent cohorts were applied in the current study. Firstly, miR-193a-3p level was detected in 125 cases of NSCLC with quantitative real-time PCR (qRT-PCR). Secondly, AEG-1 protein level was evaluated in 339 cases of lung cancers with immunohistochemistry. Finally, the relationship between miR-193a-3p and AEG-1 protein expression was verified in another group with 65 cases of NSCLC.

Results: The results showed that miR-193a-3p level was decreased in NSCLC tissues and significantly negatively related to tumor size (r = -0.277, P = 0.002), clinical TNM stage (r = -0.226, P = 0.011), lymph node metastasis (r = -0.186, P = 0.038), epidermal growth factor receptor (EGFR) protein level (r = -0.272, P = 0.041). On the contrary, AEG-1 protein expression was up-regulated in NSCLC and positively relative to tumor size (r = 0.240, P < 0.001), TNM stages (r = 0.164, P = 0.002) and lymph node metastasis (r = 0.232, P < 0.001) in NSCLC patients. In addition, miR-193a-3p was found to be inversely associated with AEG-1 protein expression in the third cohort (r = -0.564, P < 0.001).

Conclusion: In conclusion, miR-193a-3p and AEG-1 might be responsible for the carcinogenesis and aggressiveness of NSCLC. AEG-1 has the potential to be one of the targeted genes of miR-193a-3p. However, future in vitro and in vivo experiments are needed to verify this hypothesis.

Keywords: Astrocyte elevated gene-1; Carcinogenesis; Metastasis; MicroRNA-193a-3p; Non-small cell lung cancer.