Transcription factor GATA6 promotes migration of human coronary artery smooth muscle cells in vitro

PLAU, transcriptionally negatively regulated by GATA6, promotes lung squamous carcinoma cell proliferation and migration

BACKGROUND

Lung squamous cell carcinoma (LUSC) is associated with high mortality and has limited therapeutic treatment options. Plasminogen activator urokinase (PLAU) plays important roles in tumor cell malignancy. However, the oncogenic role of PLAU in the progression of LUSC remains unknown. GATA-binding factor 6 (GATA6), a key regulator of lung development, inhibits LUSC cell proliferation and migration, but the underlying regulatory mechanism remains to be further explored. Moreover, the regulatory effect of GATA6 on PLAU expression has not been reported. The aim of this study was to identify the role of PLAU and the transcriptional inhibition mechanism of GATA6 on PLAU expression in LUSC.

METHODS

To identify the potential target genes regulated by GATA6, differentially expressed genes (DEGs) obtained from GEO datasets analysis and RNA-seq experiment were subjected to Venn analysis and correlation heatmap analysis. The transcriptional regulatory effects of GATA6 on PLAU expression were detected by real-time PCR, immunoblotting, and dual-luciferase reporter assays. The oncogenic effects of PLAU on LUSC cell proliferation and migration were evaluated by EdU incorporation, Matrigel 3D culture and Transwell assays. PLAU expression was detected in tissue microarray of LUSC via immunohistochemistry (IHC) assay. To determine prognostic factors for prognosis of LUSC patients, the clinicopathological characteristics and PLAU expression were subjected to univariate Cox regression analysis.

RESULTS

PLAU overexpression promoted LUSC cell proliferation and migration. PLAU is overexpressed in LUSC tissues compared with normal tissues. Consistently, high PLAU expression, which acts as an independent risk factor, is associated with poor prognosis of LUSC patients. Furthermore, the expression of PLAU is transcriptionally regulated by GATA6.

CONCLUSION

In this work, it was revealed that PLAU is a novel oncogene for LUSC and a new molecular regulatory mechanism of GATA6 in LUSC was unveiled. Targeting the GATA6/PLAU pathway might help in the development of novel therapeutic treatment strategies for LUSC.

Smooth Muscle Heterogeneity and Plasticity in Health and Aortic Aneurysmal Disease

Vascular smooth muscle cells (VSMCs) are the predominant cell type in the medial layer of the aorta, which plays a critical role in the maintenance of aortic wall integrity. VSMCs have been suggested to have contractile and synthetic phenotypes and undergo phenotypic switching to contribute to the deteriorating aortic wall structure. Recently, the unprecedented heterogeneity and diversity of VSMCs and their complex relationship to aortic aneurysms (AAs) have been revealed by high-resolution research methods, such as lineage tracing and single-cell RNA sequencing. The aortic wall consists of VSMCs from different embryonic origins that respond unevenly to genetic defects that directly or indirectly regulate VSMC contractile phenotype. This difference predisposes to hereditary AAs in the aortic root and ascending aorta. Several VSMC phenotypes with different functions, for example, secreting VSMCs, proliferative VSMCs, mesenchymal stem cell-like VSMCs, immune-related VSMCs, proinflammatory VSMCs, senescent VSMCs, and stressed VSMCs are identified in non-hereditary AAs. The transformation of VSMCs into different phenotypes is an adaptive response to deleterious stimuli but can also trigger pathological remodeling that exacerbates the pathogenesis and development of AAs. This review is intended to contribute to the understanding of VSMC diversity in health and aneurysmal diseases. Papers that give an update on VSMC phenotype diversity in health and aneurysmal disease are summarized and recent insights on the role of VSMCs in AAs are discussed.