A microRNA disease signature associated with lymph node metastasis of lung adenocarcinoma.

Background: Lymph node metastasis (LNM) of lung cancer is an important factor associated with prognosis. Dysregulated microRNAs (miRNAs) are becoming a new powerful tool to characterize tumorigenesis and metastasis. We have developed and validated a miRNA disease signature to predict LNM in lung adenocarcinoma (LUAD). Method: LUAD miRNAs and clinical data from The Cancer Genome Atlas (TCGA) were obtained and divided randomly into training (n = 259) and validation (n = 83) cohorts. A miRNA signature was built using least absolute shrinkage and selection operator (LASSO) (λ =-1.268) and logistic regression model. The performance of the miRNA signature was evaluated using the area under curve (AUC) of receiver operating characteristic curve (ROC). We performed decision curve analysis (DCA) to assess the clinical usefulness of the signature. We also conducted a miRNA-regulatory network analysis to look for potential genes engaged in LNM in LUAD. Result: Thirteen miRNAs were selected to build our miRNA disease signature. The model showed good calibration in the training cohort, with an AUC of 0.782 (95% CI: 0.725-0.839). In the validation cohort, AUC was 0.691 (95% CI: 0.575-0.806). DCA demonstrated that the miRNA signature was clinically useful. Conclusion: The miRNA disease signature can be used as a noninvasive method to predict LNM in patients with lung adenocarcinoma objectively and the signature achieved high accuracy for prediction.

Effects of insulin-like growth factor 1 receptor and its inhibitor AG1024 on the progress of lung cancer.

The type 1 insulin-like growth factor receptor (IGF-1R) and its downstream signaling components have been increasingly recognized to drive the development of malignancies, including non-small cell lung cancer (NSCLC). This study aimed to investigate the effects of IGF-1R and its inhibitor, AG1024, on the progression of lung cancer. Tissue microarray and immunohistochemistry were employed to detect the expressions of IGF-1 and IGF-1R in NSCLC tissues (n=198). Western blotting was used to determine the expressions of IGF-1 and phosphorylated IGF-1R (p-IGF-1R) in A549 human lung carcinoma cells, and MTT assay to measure cell proliferation. Additionally, the expressions of IGF-1, p-IGF-1R and IGF-1R in a mouse model of lung cancer were detected by Western blotting and real-time fluorescence quantitative polymerase chain reaction (FQ-PCR), respectively. The results showed that IGF-1 and IGF-1R were overexpressed in NSCLC tissues. The expression levels of IGF-1 and p-IGF-1R were significantly increased in A549 cells treated with IGF-1 as compared to those treated with IGF-1+AG1024 or untreated cells. In the presence of IGF-1, the proliferation of A549 cells was significantly increased. The progression of lung cancer in mice treated with IGF-1 was significantly increased as compared to the group treated with IGF-1+AG1024 or the control group, with the same trend mirrored in IGF-1/p-IGF-1R/IGF-1R at the protein and/or mRNA levels. It was concluded that IGF-1 and IGF inhibitor AG1024 promotes lung cancer progression.