ABSTRACT
Pancreatic cancer remains the common cancer with the worst prognosis because of its late diagnosis and extensive metastasis. This study aimed to investigate the effects of GABRP on pancreatic cancer metastasis and the molecular mechanism. The expression of GABRP was measured using the quantitative real-time PCR and western blot. The biological behaviors of cancer cells were assessed using the cell counting kit-8, Transwell assay, and western blot. The regulation of GABRP on the MEK/ERK pathway was detected by western blot. The results indicated that GABRP was overexpressed in pancreatic cancer tissues and cells. Knockdown of GABRP suppressed cell viability, invasion, migration, and epithelial-mesenchymal transition (EMT), whereas GABRP overexpression facilitated these biological behaviors. Inactivation of the MEK/ERK pathway reversed the effects on cellular processes induced by GABRP. Moreover, silencing of GABRP inhibited tumor growth. In conclusion, GABRP promoted the progression of pancreatic cancer by facilitating cell metastasis and tumor growth via activating the MEK/ERK pathway. The findings suggest that GABRP has the potential to be a therapeutic target for the metastatic pancreatic cancer.
Subject(s)
MAP Kinase Signaling System , Pancreatic Neoplasms , Humans , Cell Line, Tumor , Cell Movement , Cell Proliferation , Gene Expression Regulation, Neoplastic , Mitogen-Activated Protein Kinase Kinases/metabolism , Pancreatic Neoplasms/pathology , Receptors, GABA-A/genetics , Receptors, GABA-A/metabolism , Signal TransductionABSTRACT
BACKGROUND: The interface zone, area around invasive carcinoma, can be thought of as the actual tissue of the tumor microenvironment with precedent alterations for tumor invasion. However, the heterogeneity and characteristics of the microenvironment in the interface area have not yet been thoroughly explored. METHODS: For in vitro studies, single-cell RNA sequencing (scRNA-seq) was used to characterize the cells from the tumor zone, the normal zone and the interface zone with 5-mm-wide belts between the tumor invasion front and the normal zone. Through scRNA-seq data analysis, we compared the cell types and their transcriptional characteristics in the different zones. Pseudotime, cell-cell communication and pathway analysis were performed to characterize the zone-specific microenvironment. Cell proliferation, wound healing and clone formation experiments explored the function of differentially expressed gene BMPR1B, which were confirmed by tumor models in vivo. RESULTS: After screening, 88,548 high-quality cells were obtained and identified. Regulatory T cells, M2 macrophages, angiogenesis-related mast cells, stem cells with weak DNA repair ability, endothelial cells with angiogenic activity, fibroblasts with collagen synthesis and epithelial cells with proliferative activity form a unique tumorigenic microenvironment in the interface zone. Cell-cell communication analysis revealed that there are special ligand-receptor pairs between different cell types in the interface zone, which protects endothelial cell apoptosis and promotes epithelial cell proliferation and migration, compared to the normal zone. Compared with the normal zone, the highly expressed BMPR1B gene promotes the tumorigenic ability of cancer cells in the interface zone. CONCLUSIONS: Our work identified a unique tumorigenic microenvironment of the interface zone and allowed for deeper insights into the tumor microenvironment of breast cancer that will serve as a helpful resource for advancing breast cancer diagnosis and therapy.
