Impact of Additional Anomalies on Postnatal Outcomes in Congenital Lung Malformations

The Role of the miR-548au-3p/CA12 Axis in Tracheal Chondrogenesis in Congenital Pulmonary Airway Malformations

Background

Literature has identified differentially expressed miRNAs in congenital pulmonary airway malformation (CPAM). However, the functional role of these miRNAs in CPAM remains unclear.

Methods

We obtained diseased lung tissues as well as adjacent normal lung tissue from CPAM patients attending the centre. Hematoxylin and eosin (H&E) and Alcian blue staining were performed. Differentially expressed mRNA expression profile was CPAM tissue, and matched normal tissue specimens were examined by high-throughput RNA sequencing. CCK-8 assay, EdU staining, TUNEL staining, flow cytometry, and the Transwell assay were performed to investigate the effect of miR-548au-3p/CA12 axis on proliferation, apoptosis, and chondrogenic differentiation in rat tracheal chondrocytes. mRNA and protein expression levels were determined using reverse transcription-quantitative PCR and western blot analysis, respectively. The relationship between miR-548au-3p and CA12 was evaluated using the luciferase reporter assay.

Results

The expression level of miR-548au-3p was significantly increased in diseased tissues compared with normal adjacent tissues from patients with CPAM. Our results indicate that miR-548au-3p functions as a positive regulator in rat tracheal chondrocyte proliferation and chondrogenic differentiation. At molecular level, miR-548au-3p promoted N-cadherin, MMP13, and ADAMTS4 expressions and reduced E-cadherin, aggrecan, and Col2A1 expressions. CA12 has been previously reported as a predicted target of miR-548au-3p, and here, we show that overexpression of CA12 in rat tracheal chondrocyte mimics the effects of inhibition of miR-548au-3p. On the other hand, CA12 knockdown reversed the effects of miR-548au-3p on cell proliferation, apoptosis, and chondrogenic differentiation.

Conclusions

In conclusion, the miR-548au-3p/CA12 axis plays a role in the pathogenesis of CPAM and may lead to identification of new approaches for CPAM treatment.

Analysis of miRNA Profiles and the Regulatory Network in Congenital Pulmonary Airway Malformations

Background: Specific diagnostic markers for congenital pulmonary airway malformations (CPAMs) have not yet been discovered. This study intends to detect differentially expressed miRNAs in type I and type II CPAMs by using a miRNA chip and clarify the feasibility of miRNAs as different CPAM typing markers. Methods: Lung tissues of type I and type II CPAMs were collected and used to assess the differentially expressed miRNAs using a miRNA chip after evaluation using hematoxylin-eosin staining and Masson staining. Quantitative reverse transcription-polymerase chain reaction and fluorescence in situ hybridization were used to verify the quality of the miRNA chip. The function and pathways of related differentially expressed miRNAs were analyzed by Gene Ontology Enrichment (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, respectively. Targets of miRNAs were predicted by targetscan7.1 and mirdbV6 and the network between miRNA and mRNA was established using Cystoscope software. Results: In total, 394/34 upregulated and 321/72 downregulated miRNAs were found in type I and type II CPAMs, respectively. GO and KEGG analysis showed that different pathways are involved in the regulation of CPAM, including platelet activation, Ras, MAPK, FoxO, and PI3K-Akt signaling pathways. miRNA-mRNA network analysis confirmed four major miRNAs in CPAM, including miR-4731-5p to complexin 2, miR-3150a-3p to vesicle amine transport 1, miR-32-5p to F-box and WD repeat domain containing 7, and miR-454-3p to SLAIN motif family member 1. Conclusion: In summary, we have identified four candidate miRNAs and pathways related to different pattern CPAMs, which provide a new perspective for CPAM research and treatment.