Recently, increasing studies of miRNA expression profiling has confirmed that miRNA plays an essential role in non-small cell lung cancer (NSCLC). However, inconsistent or discrepant results exist in these researches. In present study, we performed an integrative analysis of 32 miRNA profiling studies compared the differentially expressed miRNA between NSCLC tissue and non-cancerous lung tissue to identify candidate miRNAs associated with NSCLC. 7 upregulated and 10 downregulated miRNAs were identified as miRNA integrated-signature using Robust Rank Aggregation (RRA) method. qRT-PCR demonstrated that miR-21-5p, miR-210, miR-205-5p, miR-182-5p, miR-31-5p, miR-183-5p and miR-96-5p were up-regulated, whereas miR-126-3p, miR-30a-5p, miR-451a, miR-143-3p and miR-30d-5p were down-regulated more than 2 folds in the NSCLC, which was further validated in Tumor Cancer Genome Atlas (TCGA) database. Receiver operating characteristic (ROC) curve analysis confirmed that 9 miRNAs had good predictive performance (AUC > 0.9). Cox regression analysis revealed that miR-21-5p (hazard ratio [HR]: 1.616, 95% CI: 1.114–2.342, p = 0.011) and miR-30d-5p (HR: 0.578, 95% CI: 0.400–0.835, p = 0.003) were independent prognostic factors in NSCLC for overall survival. The accumulative effects of the two miRNAs on the prognosis of NSCLC were further estimated. The results showed that patients with two positive markers had a worse prognosis than those with one or none positive marker. In conclusion, this study contributes to the comprehension of the role of miRNAs in NSCLC and provides a basis for further clinical application.

ObjectivesMicroRNAs (miRNAs) play essential roles in the development of COPD. In this study, we aimed to identify and validate potential miRNA biomarkers in frequent and non-frequent exacerbators of COPD patients using bioinformatic analysis.Materials and methodsThe candidate miRNA biomarkers in COPD were screened from Gene Expression Omnibus (GEO) dataset and identified using GEO2R online tool. Then, we performed bioinformatic analyses including target prediction, gene ontology (GO), pathway enrichment analysis and construction of protein–protein interaction (PPI) network. Furthermore, the expression of the identified miRNAs in peripheral blood monocular cells (PBMCs) of COPD patients was validated using quantitative real-time polymerase chain reaction (qRT-PCR).ResultsMiR-23a, miR-25, miR-145 and miR-224 were identified to be significantly downregulated in COPD patients compared with healthy controls. GO analysis showed the four miRNAs involved in apoptotic, cell differentiation, cell proliferation and innate immune response. Pathway analysis showed that the targets of these miRNAs were associated with p53, TGF-β, Wnt, VEGF and MAPK signal pathway. In healthy controls, the miR-25 and miR-224 levels were significantly decreased in smokers compared with nonsmokers (P<0.001 and P<0.05, respectively). In COPD patients, the levels of miR-23a, miR-25, miR-145 and miR-224 were associated with Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages. Notably, miR-23a and miR-145 were significantly elevated in non-frequent exacerbators compared with frequent exacerbators (P<0.05), and miR-23a showed higher area under the receiver–operator characteristic curve (AUROC) than miR-145 (0.707 vs 0.665, P<0.05).ConclusionMiR-23a, miR-25, miR-145 and miR-224 were associated with the development of COPD, and miR-23a might be a potential biomarker for discriminating the frequent exacerbators from non-frequent exacerbators.

Rationale:Bronchobiliary fistula (BBF) is a rare clinical condition which is characterized by a channel between biliary tract and bronchial tree. BBF can present with fever, dyspnea, and cough. However, it can be easily misdiagnosed as biliary vomiting, dyspnea, or even severe pneumonia.Patient concerns:A 53-year-old woman was diagnosed with breast cancer in April 2011 and underwent radical mastectomy and lymph node dissection, chemotherapy, and radiotherapy. Unfortunately, the patient suffered from bone metastasis during the 1st year and liver metastasis during the 2nd year after radical mastectomy. In 2013, the patient underwent transcatheter arterial chemoembolization therapy twice for liver metastasis. The patient was then treated with radiofrequency ablation (RFA) in 2016. Unfortunately, the patient developed a cough with bitter-tasting yellow sputum and chest tightness 2 weeks after the RFA treatment. Approximately 6 months later, the patient still complained of a cough with yellow sputum and persistent chest tightness. The patient was then admitted to our department.Diagnoses:The presence of bile in the sputum supported a diagnosis of BBF. Bronchoscopy was performed, and the presence of bile in the lavage fluid confirmed the diagnosis of BBF.Interventions:The patient was treated with antibiotics including sulbactam, cefoperazone, levofloxacin and meropenem, was well as hepatoprotectants, nutritional support and other supportive treatments in our department.Outcomes:The patient died because of liver failure.Lessons:This case demonstrates that we should consider the possibility of BBF when patients experience a recurrent cough with discolored sputum after RFA. In particular, a diagnosis of BBF should be considered in patients who do not respond to antibiotic treatment.