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Increasing evidence has shown that microRNA (miRNA) is extensively involved in the pathophysiology of lung cancer. Microarray data demonstrated the increasing levels of miR-19a in the peripheral blood from patients suffering from lung cancer, which is closely associated with poor prognosis of lung cancer. However, the underlying molecular mechanism of miR-19a remains to be determined. The results of the present study showed a higher expression of miR-19a compared with normal bronchial epithelial cells. Furthermore, lentivirus vectors were constructed to establish cell lines that overexpressed and knocked out miR-19a in order to study the role of miR-19a on the metastasis and proliferation of lung cancer cells. Investigation into the underlying mechanism of miR-19a, revealed that MXD1 may be the key gene targeting miR-19a, participating in the process of proliferation and metastasis of lung cancer cells.

Accumulation of single nucleotide polymorphisms (SNPs) in the displacement loop (D-loop) of mitochondrial DNA (mtDNA) may be associated with an increased cancer risk. We investigated the lung cancer risk profile of D-loop SNPs in a case-controlled study. The minor alleles of nucleotides 235A/G and 324A/G were associated with an increased risk for lung cancer patients. The minor alleles of the nucleotides 151C/T, 200A/G, 524C/CA, and 16274G/A were specifically associated with the cancer risk of squamous cell carcinoma, whereas the minor allele of nucleotide 16298T/C was specifically associated with the risk of small cell lung cancer. In conclusion, SNPs in mtDNA are potential modifiers of lung cancer risk. The analysis of genetic polymorphisms in the mitochondrial D-loop can help identify subgroups of patients who are at a high risk of developing lung cancer.

To establish a new method for detecting the bronchus responsible for pulmonary air leakage by injecting methylene blue saline and to evaluate its efficacy and safety in cases with intractable pneumothorax and bronchial fistula.From January 2006 to October 2013, a total of 19 cases of intractable spontaneous pneumothorax and 8 cases of bronchial fistula were recruited in the study at the Fourth Hospital affiliated to Hebei Medical University. Of all the cases, 15 were diagnosed as having tension pneumothorax and 12 as having communicating pneumothorax. All the cases failed to respond to continuous pleural suction for more than 5 days and consented to the proposed treatment. Before procedure, chest suction was established to allow sustained airflow through the drainage tube while the patients breathed normally. Under direct vision through fiberoptic bronchoscope, injection catheter was inserted into the bronchoscopy channel, and methylene blue saline was slowly injected into the potentially leaking segmental or sub-segmental bronchi. When a steady decline or disappearance in the amount of methylene blue saline in the airways was observed, or methylthionine-tainted saline was detected within the chest drainage tube, the bronchus responsible for air leakage was indicated. Before blocking the target bronchus, the negative pressure level of pleural suction should be reduced or stopped, and then porcine fibrin glue or a-cyanoacrylate was used for sealing the bronchi associated with air leakage. When the air was absent from the drainage tube, and lung recruitment was indicated in the chest X-ray for 5 days, and bronchial blockade of air leakage was proved successful.The bronchi responsible for air leakage were successfully located in all 27 cases, among them segmental bronchi were located in 16, subsegmental bronchi in 10, and small subsegmental bronchus in only one. Multiple adjacent segmental involvement occurred in 3, and multiple adjacent subsegmental involvement in 5 cases. The average time for locating the target bronchi was (51 ± 9) s, among them the average time for tension pneumothorax was (48 ± 15) s compared with (53 ± 16) s for communicating pneumothorax (t = 0.416, P = 0.699) . The average amount of methylene blue saline consumed for locating the target bronchi was (42 ± 23) ml. During the procedure, the membrane of the bronchi was kept intact, and the vital signs were stable. Blockade of the target bronchi was successful with fibrin glue in 20 cases and with OB glue in 7 cases. A total of 61 times of bronchial blocking were performed, and the airflow of the chest drainage tube was instantly stopped in 17 times, gradually stopped in 10, steadily reduced in 22 and no change in 12 times. Adverse effects included severe cough in 4 cases, fever in 3, pleural hemorrhage in 3, and chest pain, atelectasis, and pneumonia in 2 cases, respectively.The bronchi responsible for pulmonary air leakage in patients with spontaneous pneumothorax and bronchial fistula could be determined by injecting methylene blue saline into the airways. This novel method does not require special instruments, and is easy to perform with a high safety and effectiveness.

Ping Wang,1 Liqiang Song,2 Hui Ge,1 Pule Jin,1 Yifang Jiang,1 Wenxia Hu,1 Nan Geng1 1Department of Respiratory Medicine, Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, People's Republic of China; 2Department of Pathology, School of Basic Medical Sciences, Peking Union Medical College, Beijing, People's Republic of China Abstract: Platelet-derived growth factor (PDGF) and its receptors (PDGFR), including PDGFRα and PDGFRβ, play important roles in tumorigenesis, tumor progression, and the regulation of stromal cell function. Constitutive activation of PDGFR signaling, gene rearrangement, and activating mutations of PDGFR have been identified in various types of human tumors and malignancies. PDGFRα and PDGFRβ belong to the family of type III receptor tyrosine kinases and, upon stimulation, activate downstream signaling cascades. Crenolanib is a specific tyrosine kinase inhibitor that targets and inhibits the kinase activity of PDGFR and the FMS-related tyrosine kinase 3. Its clinical efficacy in several human tumors is currently under investigation in Phase II clinical trials. In this study, we examined the potential role of crenolanib in the treatment of non-small-cell lung cancer (NSCLC). Using A549 cells as a model system, we have shown that crenolanib is capable of suppressing proliferation and inducing apoptosis in a dose-dependent manner. Crenolanib-treated cells have reduced migratory activity in response to inducers of chemotaxis. Furthermore, the in vivo antitumor activity of crenolanib was confirmed in an NSCLC xenograft tumor model. Injection of crenolanib significantly inhibited the growth of tumor mass by inducing apoptosis in tumor cells. Our results provide strong evidence supporting the use of crenolanib as a potential therapeutic agent in treating NSCLC. This work sets a foundation for further development of targeted and personalized therapeutics for lung cancer. Keywords: platelet-derived growth factor receptor signaling, receptor tyrosine kinase, tyrosine kinase inhibitor, non-small-cell lung cancer, chemotherapy, targeted therapy