Diagnostic and prognostic value of serum miR-145 and vascular endothelial growth factor in non-small cell lung cancer

Abstract

Previous studies have reported the diagnostic and prognostic value of serum microRNA (miR)-145 and vascular endothelial growth factor (VEGF) levels in various types of cancer; however, their clinical use in non-small cell lung cancer (NSCLC) remains unclear. The present study included 215 patients, 106 with NSCLC and 109 with other lung diseases (OLDs). miR-145 expression levels were determined using reverse transcription-quantitative PCR (RT-qPCR) and VEGF levels were measured using an ELISA. The diagnostic performance was assessed using a receiver operating characteristic curve and area under the curve (AUC) analysis. A Kaplan-Meier survival curve and Cox regression analysis were employed to evaluate the prognostic significance of the markers. The biological function of miR-145 was examined in A549 and H1792 cell lines. The effects of miR-145 on cell proliferation of NSCLC cells were evaluated by flow cytometry, and the expression levels of miR-145 and cell cycle-related genes were determined by RT-qPCR. The results revealed that miR-145 and VEGF exhibited fair diagnostic performance [AUC, 0.61 (95% CI, 0.55-0.68) and AUC, 0.64 (95% CI, 0.57-0.71), respectively]. Combining age and smoking status with miR-145 and VEGF provided the best model for differentiating patients with NSCLC from those with OLDs (AUC, 0.76; 95% CI, 0.69-0.83). Furthermore, low serum miR-145 levels were associated with poor overall survival [hazard ratio (HR), 0.48; 95% CI, 0.27-0.85], whereas high VEGF levels were not associated with poor overall survival (HR, 1.47; 95% CI, 0.81-2.68). In addition, the results of the in vitro experiments indicated that miR-145 decreased cell proliferation via the induction of cell cycle arrest. In conclusion, the findings of the present study suggested that combining miR-145 and VEGF levels with clinical risk factors may be a potential diagnostic scheme for NSCLC. In addition, serum miR-145 may be used as a prognostic marker. These results indicated that miR-145 may function as a tumor suppressor in NSCLC.

Keywords: NSCLC; VEGF; diagnostic; miR-145; prognostic; serum.

Figure 1.

(A and B) Receiver operating characteristic curve analysis for the diagnosis of NSCLC. Kaplan-Meier curves of overall survival of patients with NSCLC according to (C) miR-145 expression and (D) VEGF levels. AUC, area under the curve; NSCLC, non-small cell lung cancer; miR, microRNA; VEGF, vascular endothelial growth factor.

Figure 2.

Reverse transcription-quantitative PCR analysis was performed to detect miR-145 expression in (A) A549 and (B) H1792 cells. Effect of upregulated miR-145 expression on viability was determined using a trypan blue assay in (C) A549 and (D) H1792 cells, and using a viability assay in (E) A549 and (F) H1792 cells. The cell group was set as 100%. All experiments were performed in triplicate on cell-culture passages 10-30. Data are presented as the mean ± SD of three independent experiments. ^{OL-23-01-13130}P≤0.001 vs. cell group. miR, microRNA; NC, negative control.

Figure 3.

(A and B) Cell cycle progression was analyzed via flow cytometry in A549 cells. (C) Expression of cell cycle regulatory genes was determined using reverse transcription-quantitative PCR. All experiments were performed in triplicate on cell-culture passages 10–30. Data are presented as the mean ± SD from three independent experiments. ***P≤0.001, **P≤0.01, *P≤0.05 vs. cell group. miR, microRNA; NC, negative control.

Figure 4.

(A and B) Cell cycle progression was determined using flow cytometry in H1792 cells. (C) Expression of cell cycle regulatory genes was determined using reverse transcription-quantitative PCR. All experiments were performed in triplicate on cell-culture passages 10–30. Data are presented as the mean ± SD from three independent experiments. ***P≤0.001, **P≤0.01, *P≤0.05 vs. cell group. miR, microRNA; NC, negative control.