Background: In previous study, we confirmed that the miR-130a-5p/Foxa2 axis regulates fetal lung development in congenital diaphragmatic hernia (CDH). We also showed that miR-130a-5p and Foxa2 in lung tissues were localized to the epithelial cells. However, the biological functions of the miR-130a-5p/Foxa2 axis in pulmonary epithelial cells have yet to be fully elucidated. In the present study, we focused on the effect of the miR-130a-5p/Foxa2 axis on the proliferation and apoptosis of pulmonary epithelial cells and explored the mechanisms underlying these processes. Methods: We investigated the roles of miR-130a-5p and Foxa2 with regards to cell viability and apoptosis, by transfecting miR-130a-5p mimics/inhibitors, and Foxa2 overexpressed lentivirus/siRNA, into BEAS-2B cells. We also conducted the CCK-8 assay, EdU staining, and flow cytometry. Chromatin Immunoprecipitation-sequencing (ChIP-Seq) and ChIP-PCR were applied to study the molecular mechanism of miR-130a-5p/Foxa2 axis affecting the the biological properties of pulmonary epithelial cells. Results: We found that the upregulation of miR-130a-5p suppressed cell proliferation and promoted apoptosis, while the downregulation of miR-130a-5p had the opposite effects. Upregulation of the direct target gene of miR-130a-5p, Foxa2, was able to rescue the effects of miR-130a-5p in Human bronchial epithelial (BEAS-2B) cells. Chip-seq and Chip-PCR assays identified potential transcription factor functions for Foxa2; Gli3 and Eya3 were identified as binding sites for Foxa2, and the potential mechanism required our further study. Conclusions: The results showed that miR-130a-5p/Foxa2 axis played an important role in the epigenetic modification of pulmonary epithelial cells, and our current findings provided a potential mechanism for lung branching morphogenesis.

Objectives: To analyze preterm birth related factors for single intrauterine death in monochorionic twins. Design: Retrospective case-control study. Setting: A single medical centre in Shenyang, China, 2012-2018. Sample: preterm delivery with intrauterine fetal death in monochorionic twins (cases, n = 35) were compared with a group of full term birth (controls, n = 4). Methods: Related factors were compared in the two groups and logistic regression was used to adjust for confounding. Main outcome measures: Odds ratio (OR) and 95% confidence interval (CI) for the related factors of preterm birth Results: This study included 39 monochorionic twins following single intrauterine death. The significant risk factor associated with preterm birth is the gestational age of single intrauterine death (OR=1.317, 95% CI: 1.027-1.689). The timing of prolong gestational age shorten with the increasing gestational age of single intrauterine death. We found that in all monochorionic twins cases and spontaneous preterm birth cases, increases in the gestational age at single intrauterine death was associated with shorter prolongation of gestational age in the surviving twin. Conclusions: The gestational age of single intrauterine death was a risk factor of preterm delivery. Increases in the gestational age at single intrauterine death led to a shorter prolongation in gestation of the surviving twin. Funding: This study was funded by Prenatal diagnosis, intrauterine intervention and prognosis evaluation of complicated twins (No. 2018YFC1002902) Tweetable abstract: The gestational age of intrauterine fetal death was a risk factor of preterm delivery. Keywords Gestational age; Prolongation of gestational age; Twin pregnancy；