Endoscopic reflux esophagitis and decline in pulmonary function in nonsmokers: A retrospective cohort study.

BACKGROUND: The association between reflux esophagitis and pulmonary function remains controversial. Thus, evaluating the relationship between endoscopic reflux esophagitis and changes in pulmonary function over time in a nonsmoking population is an important clinical issue. METHODS: In this single-center retrospective cohort study, a medical examination database at Kameda Medical Center Makuhari was employed to identify nonsmokers who underwent upper gastrointestinal endoscopy and spirometry in 2010 and were followed up in 2015. Gastroenterologists carefully double-checked the diagnosis of reflux esophagitis. Multiple linear regression analyses were performed to compare the decline in the percentage of predicted vital capacity (%VC), forced vital capacity (%FVC), and forced expiratory volume in 1 s (%FEV1) between participants with reflux esophagitis and those without. Furthermore, using multivariable logistic regression analyses, we evaluated the factors associated with rapid decline in %VC, %FVC, and %FEV1, which is defined as a decrease of >10% in each parameter over the 5-year observation period. RESULTS: We identified 3098 eligible subjects, including 72 and 44 participants who had a Los Angeles classification grade A and B-C (severe) reflux esophagitis in 2010, respectively. The decline in %VC was significantly larger in the participants with severe reflux esophagitis than in the control subjects (standardized coefficient, -0.037; 95% confidence interval, -0.071 to -0.004). Moreover, reflux esophagitis was significantly associated with a rapid decline in %VC and %FVC but not in %FEV1 (P for trend: 0.009, 0.009, and 0.276, respectively). CONCLUSIONS: Severe reflux esophagitis among nonsmokers had clinical disadvantages in terms of a decline in %VC.

Distinct microRNA Signature and Suppression of ZFP36L1 Define ASCL1-Positive Lung Adenocarcinoma.

Achaete-scute family bHLH transcription factor 1 (ASCL1) is a master transcription factor involved in neuroendocrine differentiation. ASCL1 is expressed in approximately 10% of lung adenocarcinomas (LUAD) and exerts tumor-promoting effects. Here, we explored miRNA profiles in ASCL1-positive LUADs and identified several miRNAs closely associated with ASCL1 expression, including miR-375, miR-95-3p/miR-95-5p, miR-124-3p, and members of the miR-17∼92 family. Similar to small cell lung cancer, Yes1 associated transcriptional regulator (YAP1), a representative miR-375 target gene, was suppressed in ASCL1-positive LUADs. ASCL1 knockdown followed by miRNA profiling in a cell culture model further revealed that ASCL1 positively regulates miR-124-3p and members of the miR-17∼92 family. Integrative transcriptomic analyses identified ZFP36 ring finger protein like 1 (ZFP36L1) as a target gene of miR-124-3p, and IHC studies demonstrated that ASCL1-positive LUADs are associated with low ZFP36L1 protein levels. Cell culture studies showed that ectopic ZFP36L1 expression inhibits cell proliferation, survival, and cell-cycle progression. Moreover, ZFP36L1 negatively regulated several genes including E2F transcription factor 1 (E2F1) and snail family transcriptional repressor 1 (SNAI1). In conclusion, our study revealed that suppression of ZFP36L1 via ASCL1-regulated miR-124-3p could modulate gene expression, providing evidence that ASCL1-mediated regulation of miRNAs shapes molecular features of ASCL1-positive LUADs. IMPLICATIONS: Our study revealed unique miRNA profiles of ASCL1-positive LUADs and identified ASCL1-regulated miRNAs with functional relevance.

TGF-ß-mediated epithelial-mesenchymal transition and tumor-promoting effects in CMT64 cells are reflected in the transcriptomic signature of human lung adenocarcinoma.

Epithelial-mesenchymal transition (EMT) is a cellular process during which epithelial cells acquire mesenchymal phenotypes. Cancer cells undergo EMT to acquire malignant features and TGF-ß is a key regulator of EMT. Here, we demonstrate for the first time that TGF-ß could elicit EMT in a mouse lung adenocarcinoma cell line. TGF-ß signaling activation led to cell morphological changes corresponding to EMT and enhanced the expression of mesenchymal markers and EMT-associated transcription factors in CMT64 lung cancer cells. RNA-sequencing analyses revealed that TGF-ß increases expression of Tead transcription factors and an array of Tead2 target genes. TGF-ß stimulation also resulted in alternative splicing of several genes including Cd44, tight junction protein 1 (Tjp1), and Cortactin (Cttn). In parallel with EMT, TGF-ß enhanced cell growth of CMT64 cells and promoted tumor formation in a syngeneic transplantation model. Of clinical importance, the expression of TGF-ß-induced genes identified in CMT64 cells correlated with EMT gene signatures in human lung adenocarcinoma tissue samples. Furthermore, TGF-ß-induced gene enrichment was related to poor prognosis, underscoring the tumor-promoting role of TGF-ß signaling in lung adenocarcinoma. Our cellular and syngeneic transplantation model would provide a simple and useful experimental tool to study the significance of TGF-ß signaling and EMT.