miR-205 as a biological marker in non-small cell lung cancer

Abstract

Objection: The aim of this study is to explain the significance and mechanism of miR-205 in the diagnosis and treatment of non-small cell lung cancer.

Methods: The 70 advanced NSCLC patients, treated in our hospital, were collected from 2011.10 to 2013.9, taking the tissues from cancer and adjacent tissues to measure the miR-205 expression, evaluate the AKT gene and protein expression of cancer and adjacent normal tissues by RT-PCR and Immunohistochemistry (IHC) assays and analyzing the correlation between miR-205 and AKT. Following up the patients for 2 years; Recording patients' survival time. In the cell experiment, Selecting A549 cell as research object, the cells were divided into three groups: Normal control group (NC), Blank control group (BL) and si-miR-205 transfection group (si-miR-205). Cell proliferation rate and apoptosis rate were detected by MTT method and flow cytometry; Measuring invasion and migration of difference groups by transwell and scratch testing, measured the Akt, mTOR,P21, MMP2 and MMP9 gene expression and detected Akt, p-Akt, mTOR, p-mTOR, P21, MMP2 and MMP 9 protein expression levels.

Results: Compared with adjacent normal tissue, the miR-205 and AKT gene expression level was significantly increased in NSCLC tissues (P<0.05) and the AKT protein expression was stronger than that of healthy tissues, miR-205 was positive correlation with AKT; In the overall survival, MiR-205 high expression group was significantly higher than low expression group (P<0.05). In the cell experiment, Compared with NC and BL groups, si-miR-205 could significantly reduced the biological activity of A549 cells in proliferation, invasion and migration, and promoted the apoptosis of A549 cells (P<0.05, respectively). Akt, p-Akt, mTOR, p-mTOR, P21, MMP 2 and MMP 9 gene and protein expression of si-miR-205 group were significantly compared with NC and BL groups (P<0.05, respectively).

Conclusion: miRNA-205 might serve as a potential biomarker for the prognosis of advanced NSCLC, and inhibiting miR-205 expression could decrease A549 cells biological activity by regulating Akt/mTOR/P21 and Akt/MMP 2/MMP 9signaling pathway.

Keywords: Biological activity; Biological marker; MiR-205; NSCLC.