Non–small cell lung cancer is one of the most common types of cancer, and the prognosis of non–small cell lung cancer is still poor. Recent evidence has proved that long noncoding RNA is involved in tumorigenesis. For non–small cell lung cancer, the expression profile of long noncoding RNA has been studied. Here, we identified a novel long noncoding RNA TRPM2-AS from published dataset and found TRPM2-AS is widely upregulated in non–small cell lung cancer tissues compared with adjacent non-tumor tissues. Higher expression level of TRPM2-AS was correlated with higher TNM stages and larger tumor size. Patients with high TRPM2-AS expression level had poor survival than those with low TRPM2-AS level. We silenced TRPM2-AS by small interfering RNA and found that cell proliferation was significantly inhibited after knockdown of TRPM2-AS. Annexin V/propidium iodide staining and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay confirmed that cell apoptosis increased after TRPM2-AS knockdown. Further experiments showed that silence of TRPM2-AS upregulated SHC1 and silence of SHC1 partially reversed cell apoptosis after TRPM2-AS knockdown. In summary, the novel long noncoding RNA TRPM2-AS upregulated in non–small cell lung cancer, and downregulation of TRPM2-AS promotes apoptosis in vitro.

Background: Mediastinal teratoma is a rare disease, many cases were reported before, but few articles focus on large case analyses. The objective of this article is to summarize the clinical characteristics of benign mediastinal teratoma and the experience of surgical treatment, especially thoracoscopic surgery for benign mediastinal teratoma. Methods: The clinical data of 108 patients with benign mediastinal teratoma confirmed by operation and pathology from January 1992 to January 2018 were analyzed retrospectively. The clinical symptoms, imaging examination, surgical methods and prognosis of all patients were analyzed. We compared the difference of thoracoscopic surgery and thoracotomy surgery using 102 patients underwent only chest surgery. Normally distributed continuous variables were compared by independent sample t test. Categorical variables were analyzed by chi-square test. Results: Imaging examination showed that all 108 cases of mediastinal teratoma were located in the anterior region of mediastinum. All cases underwent surgical resection, postoperative pathology confirmed that all cases were benign. 1 case was taken simple neck collar incision, 5 case was taken median thoracotomy combined with neck incision, other 102 cases were taken thoracoscopic surgery (22) or thoracotomy surgery (80). 4 cases were treated with partial pericardial resection due to adhesions, 12 cases underwent partial pericardial resection, 5 cases underwent lobectomy, 9 cases underwent wedge resection of lobe, and 2 patients underwent anonymous vein angioplasty. 1 case underwent second operation because of postoperative bleeding, 1 case of chylothorax, 1 case of recurrent laryngeal nerve injury, 2 cases of wound infection, 1 case of secondary pulmonary infection. 106 cases were followed up, period from 12 months to 10 years, no recurrence of tumor was found. Comparing to take thoracotomy surgery, patients underwent thoracoscopic surgery has strong advantage on intraoperative blood loss and hospital stay days after surgery (P < 0.05). tumor maximum diameter is larger for thoracotomy surgery group, as well as more patients suffer estimated adhesions from preoperative imaging. so we compared above parameters in patients with tumor diameter less than 10 cm with or without estimated adhesions from preoperative imaging, a strong advantage still can be found in thoracoscopic surgery group, inpatients with estimated adhesions from preoperative imaging, intraoperative blood loss (38.75 ± 15.53 vs 169.17 ± 208.82., P = 0.04) and hospital stay days after surgery (5.50 ± 0.93 vs 9.43 ± 6.54., P = 0.04) were better. In patients without estimated adhesions from preoperative imaging, intraoperative blood loss (46.67 ± 10.00 vs 110.53 ± 123.13., P = 0.06) and hospital stay days after surgery (4.70 ± 1.16 vs 7.53 ± 2.32., P = 0.01) were better. Especially, in thoracoscopic surgery group, hospital stay days after surgery was significantly shorter. Conclusion: The clinical manifestations and imaging performance of benign mediastinal teratoma were ...

Epidermal growth factor receptor-targeted tyrosine kinase inhibitors (EGFR-TKIs) have become first-line drugs used for non-small cell lung cancer (NSCLC) treatment. However, drug resistance to EGFR-TKIs will be developed inevitably due to the repeated use of these drugs. In the present study, we isolated cancer stem cells (CSCs) from the PC9 NSCLC cell line. We then observed that the PC9 CSCs showed significant resistance to erlotinib compared with the PC9 non-CSCs. Erlotinib failed to suppress the phosphorylation of PI3K and AKT in PC9 CSCs, although the EGFR was inhibited sufficiently. Mechanically, we observed aberrant upregulation of microRNA-23a (miR-23a) and downregulation of PTEN in PC9 CSCs compared to PC9 non-CSCs. Luciferase reporter assays proved that PTEN was the target of miR-23a in PC9 CSCs. Furthermore, knockdown of miR-23a enhanced the antitumor effect of erlotinib by increasing the expression of PTEN. In addition, transfection with miR-23a inhibitors promoted the erlotinib-dependent inhibition of PI3K/AKT pathway, thus, suppressing the proliferation and inducing apoptosis in PC9 CSCs. These results propose that upregulation of miR-23a is a potential mechanism associated with resistance to EGFR-TKIs in lung cancer stem cells. Inhibition of miR-23a serves as a novel therapeutic strategy to eliminate the EGFR-TKIs resistance of lung cancer stem cells.