BACKGROUND: Esophageal cancer is one of the most common malignant tumors in the world. It is urgent to prevent the development and progression of esophageal cancer. Cancer stem cells (CSCs) were reported to have the ability to initiate tumorigenesis, and reducing the stem cell-like characteristics of tumors is an important strategy to inhibit the occurrence and development of tumors. miRNAs are key regulators of the stemness of cancer. Here, we aimed to investigate the role and regulatory mechanism of miR-191-3p in the stemness properties of esophageal cancer cells.
METHODS: Esophageal cancer cells with stable expression of miR-191-3p were established by lentivirus system. CCK-8 assay, transwell assay, wound healing assay were used to evaluate the effect of miR-191-3p on proliferation and metastasis of esophageal cancer cells. The expression of stemness-related markers (NANOG, OCT4, SOX2), ALDH activity, sphere-forming assay and subcutaneous tumor model in nude mice were performed to evaluate the stemness properties of esophageal cancer cells in vitro and in vivo. Dual-luciferase reporter assay was used to verify the molecular mechanism.
RESULTS: Here we found that overexpression of miR-191-3p promoted the stemness properties of esophageal cancer cells in vitro and in vivo, including increasing esophageal cancer cell proliferation and metastasis ability, the expression of stemness-related markers NANOG, OCT4, and SOX2, ALDH activity, the number of spheres formed and tumor growth. Bioinformatic analysis and dual-luciferase assay demonstrated that regulator of G protein signaling 1 (RGS1) was the directed target gene of miR-191-3p and attenuated the promotion effect of miR-191-3p on the stemness of esophageal cancer cells. Furthermore, we found that RGS1 knockdown activated the PI3K/AKT pathway by negatively regulating CXCR4 to promote the stemness of esophageal cancer cells.
CONCLUSIONS: Our findings revealed that RGS1 targeted by miR-191-3p inhibited the stemness of esophageal cancer cells by suppressing the CXCR4/PI3K/AKT pathway, which provide potential prognostic markers and therapeutic targets in the future.

Recent evidence has highlighted the functions of enhancers in modulating transcriptional machinery and affecting the development of human diseases including rheumatoid arthritis (RA). Enhancer RNAs (eRNAs) are RNA molecules transcribed from active enhancer regions. This study investigates the specific function of eRNA in gene transcription and osteoclastogenesis in RA. Regulator of G protein signaling 1 (RGS1)-associated eRNA was highly activated in osteoclasts according to bioinformatics prediction. RGS1 mRNA was increased in mice with collagen-induced arthritis as well as in M-CSF/soluble RANKL-stimulated macrophages (derived from monocytes). This was ascribed to increased RGS1 eRNA activity. Silencing of 5\'-eRNA blocked the binding between forkhead box J3 (FOXJ3) and the RGS1 promoter, thus suppressing RGS1 transcription. RGS1 accelerated osteoclastogenesis through PLC-IP3R-dependent Ca2+ response. Knockdown of either FOXJ3 or RGS1 ameliorated arthritis severity, improved pathological changes, and reduced osteoclastogenesis and bone erosion in vivo and in vitro. However, the effects of FOXJ3 silencing were negated by RGS1 overexpression. In conclusion, this study demonstrates that the RGS1 eRNA-driven transcriptional activation of the FOXJ3/RGS1 axis accelerates osteoclastogenesis through PLC-IP3R dependent Ca2+ response in RA. The finding may offer novel insights into the role of eRNA in gene transcription and osteoclastogenesis in RA.

Global climate change is accompanied by carbon dioxide (CO2) enrichment and high temperature (HT) stress; however, how plants adapt to the combined environments and the underlying mechanisms remain largely unclear. In this study, we show that elevated CO2 alleviated plant sensitivity to HT stress, with significantly increased apoplastic glucose (Glc) levels in tomato (Solanum lycopersicum) leaves. Exogenous Glc treatment enhanced tomato resilience to HT stress under ambient CO2 conditions. Cell-based biolayer interferometry, subcellular localization, and Split-luciferase assays revealed that Glc bound to the tomato regulator of G protein signaling 1 (RGS1) and induced RGS1 endocytosis and thereby RGS1-G protein α subunit (GPA1) dissociation in a concentration-dependent manner. Using rgs1 and gpa1 mutants, we found that RGS1 negatively regulated thermotolerance and was required for elevated CO2-Glc-induced thermotolerance. GPA1 positively regulated the elevated CO2-Glc-induced thermotolerance. A combined transcriptome and chlorophyll fluorescence parameter analysis further revealed that GPA1 integrated photosynthesis- and photoprotection-related mechanisms to regulate thermotolerance. These results demonstrate that Glc-RGS1-GPA1 signaling plays a crucial role in the elevated CO2-induced thermotolerance in tomato. This information enhances our understanding of the Glc-G protein signaling function in stress resilience in response to global climate change and will be helpful for genetic engineering approaches to improve plant resilience.

Regulator of G protein signaling 1 (RGS1) is closely associated with the tumor immune microenvironment and is highly expressed in various tumors and immune cells. The specific effects of RGS1 in the dynamic progression from chronic gastritis to gastric cancer have not been reported, and the role of tumor-associated macrophages (TAMs) is also unclear. In the present study, RGS1 was identified as an upregulated gene in different pathological stages ranging from chronic gastritis to gastric cancer by using Gene Expression Omnibus (GEO) screening together with pancancer analysis of The Cancer Genome Atlas and clinical prognostic analysis. The results indicated that RGS1 is highly expressed in gastric cancer and has potential prognostic value. We confirmed through in vivo experiments that RGS1 inhibited the proliferation of gastric cancer cells and promoted apoptosis, which was further corroborated by in vitro experiments. Additionally, RGS1 influenced cell migration and invasion. In our subsequent investigation of RGS1, we discovered its role in the immune response. Through analyses of single-cell and GEO database data, we confirmed its involvement in immune cell regulation, specifically TAM activation. Subsequently, we conducted in vivo and in vitro experiments to confirm the involvement of RGS1 in polarizing M1 macrophages while indirectly regulating M2 macrophages through tumor cells. In conclusion, RGS1 could be a potential target for the transformation of chronic gastritis into gastric cancer and has a measurable impact on TAMs, which warrants further in-depth research.

UNASSIGNED: Non-responsiveness is a major barrier in current cancer immune checkpoint blockade therapies, and the mechanism has not been elucidated yet. Therefore, it is necessary to discover the mechanism and biomarkers of tumor immunotherapeutic resistance.
UNASSIGNED: Bioinformatics analysis was performed based on CD8+ T cell infiltration in multiple tumor databases to screen out genes related to anti-tumor immunity. Associations between Regulator of G-protein signaling 1 (RGS1) and IFNγ-STAT1 signaling, and MHCI antigen presentation pathway were examined by RT-qPCR, western blotting, and flow cytometry. The modulatory mechanisms of RGS1 were investigated via CHIP-qPCR and dual-luciferase assay. The clinical and therapeutic implications of RGS1 were comprehensively investigated using tumor cell lines, mouse models, and clinical samples receiving immunotherapy.
UNASSIGNED: RGS1 was identified as the highest gene positively correlated with immunogenicity among RGS family. Inhibition of RGS1 in neoplastic cells dampened anti-tumor immune response and elicited resistance to immunotherapy in both renal and lung murine subcutaneous tumors. Mechanistically, RGS1 enhanced the binding of activating transcription factor 3 (ATF3) to the promoter of interferon gamma receptor 1 (IFNGR1), activated STAT1 and the subsequent expression of IFNγ-inducible genes, especially CXCL9 and MHC class I (MHCI), thereby influenced CD8+ T cell infiltration and antigen presentation and processing. Clinically, lower expression level of RGS1 was associated with resistance of PD1 inhibition therapy and shortened progression-free survival among 21 NSCLC patients receiving immunotherapy.
UNASSIGNED: Together, these findings uncover a novel mechanism that elicits immunotherapy resistance and highlight the function of tumor-intrinsic RGS1, which brings new insights for future strategies to sensitize anti-PD1 immunotherapy.

BACKGROUND: The exact cause of intracranial aneurysms (IA) is still unclear. However, pro-inflammatory factors are known to contribute to IA progression. The specific changes in the immune microenvironment of IAs remain largely unexplored.
METHODS: This study analyzed single-cell sequencing data from a male mouse model of brain aneurysm, focusing on samples before and after elastase-induced Willis aneurysms. The data helped identify eight distinct cell subpopulations: fibroblasts, macrophages, NK cells, endothelial cells, B cells, granulocytes, and monocytes. The study also involved bulk RNA sequencing of 97 IA samples, utilizing ssGSEA and CIBERSORT algorithms for analysis. Intercellular communication among these cells was inferred to understand the immune dynamics in IA.
RESULTS: The study found that fibroblasts and macrophages are predominant in various disease states of IA. Notably, the onset of IA was marked by a significant increase in fibroblasts and a decrease in macrophages. There was a marked increase in cellular interactions, especially involving macrophages, at the onset of the disease. Through enrichment analysis, 12 potential immunogenic biomarkers were identified. Of these, Rgs1 emerged as a critical molecule in IA formation, confirmed through secondary validation in a single-cell sequencing dataset.
CONCLUSIONS: This comprehensive analysis of immune cell composition and intercellular communication in IA tissues highlights the significant roles of macrophages and the molecule Rgs1. These findings shed light on the physiological and pathological conditions of IA, offering new insights into its immune microenvironment.

Renal interstitial fibrosis (RIF) is considered as a common pathway for all patients with chronic kidney disease (CKD) to progress to end-stage kidney disease (ESRD). The basic pathological manifestation is the increase of matrix component in the tubular interstitium, while the injury of tubular epithelial cells in the renal interstitium and the excessive accumulation of matrix will eventually lead to tubular atrophy and obstruction, loss of effective renal units, and finally impaired renal filtration function. The relevant mechanism of RIF remains unclear. The present study will investigate the function and relevant mechanism of RGS1 in RIF. The RIF-related microarrays GSE22459 and GSE76882 were downloaded and analyzed. Renal parenchymal atrophic calyx tissues were collected from clinical RIF patients. Cellular inflammation, fibrosis and animal RIF models were constructed using Lipopolysaccharide (LPS), TGF-β1 and unilateral ureteral occlusion (UUO). HE and Masson staining were performed to detect morphological alterations of renal tissue samples. qRT-PCR, Western blot and ELISA were carried out to detect the expression of relevant genes/proteins. RGS1 is a gene co-differentially expressed by GSE22459 and GSE76882. RGS1 expression was elevated in renal tissues of RIF patients, cells and animal RIF models. Knockdown of RGS1 inhibited renal cell inflammatory response, fibrosis and renal fibrosis in RIF mice. Overexpression of RGS1 plays the opposite role. Knockdown of RGS1 inhibited the inflammatory response in the RIF cell and mouse model. Targeting RGS1 might be a potential therapeutic strategy for RIF treatment.

Gastric cancer is becoming the 4th leading cause of cancer-associated death worldwide. The purpose of this study was to investigate the role of RGS1 in gastric cancer in vitro and in vivo. Proliferation, migration, invasion, and colony formation of NCIN87 cells and drug-resistant NCIN87 cells (NCIN87-DR) were determined. Cell apoptosis and cell cycle were examined using a flow cytometry assay. RGS1 gene knock-down vector (pLVshshRGS1) and Xenograft tumor mouse model was generated. RGS1 and epithelial-mesenchymal transition (EMT) associated markers, including E-cadherin (E-cad), N-cadherin (N-cad), Slug, and Vimentin were detected using a western blotting assay. Tumor size of Xenograft tumor mouse was measured and Ki67 expression was detected using the immunohistochemical assay. NCIN87-DR cells demonstrated significantly lower proliferation, migration, and invasion compared to those of NCIN87 cells (p < 0.05). NCIN87-DR cells showed obvious early apoptosis and displayed obvious alterations for the cell cycle. NCIN87-DR cells exhibited predominantly higher RGS1 expression than that in NCIN87 cells (p < 0.01). E-cad expression was markedly decreased (p < 0.01) and N-cad (p < 0.05), Slug (p < 0.01), Vimentin (p < 0.05) expressions were significantly increased in NCIN87-DR cells than those in NCIN87 cells. RGS1 gene silence remarkably reduced NCIN87-DR proliferation compared to that in NCIN87-DR cells without treatment (p < 0.01). RGS1 gene-silenced NCIN87-DR cell immunization predominantly inhibited tumor growth in Xenograft tumor mouse than that without RGS1 silence (p < 0.05). RGS1 gene-silenced NCIN87-DR cell immunization significantly downregulated Ki67 expression in tumor tissues compared with that without RGS1 silence. In conclusion, RGS1 gene silence reduced the proliferation of NCIN87-DR cells in vitro and inhibited tumor growth in vivo. Therefore, RGS1 served as an antitumor target for the gastric cancer treatment.

BACKGROUND: Regulatory T cells (Tregs) are central to determine immune response, thus targeting Tregs for immunotherapy is a promising strategy against tumor development and metastasis.
OBJECTIVE: The objective of this study was to identify genes for targeting Tregs to improve the outcome of HCC.
METHODS: We integrated expression data from different samples to remove batch effects and further applied embedding function in Scanpy to conduct sub-clustering of CD4+ T cells in HCC for each of two independent scRNA-seq data. The activity of transcription factors (TFs) was inferred by DoRothEA. Gene expression network analysis was performed in WGCNA R package. We finally used R packages (survminer and survival) to conduct survival analysis. Multiplex immunofluorescence analysis was performed to validate the result from bioinformatic analyses.
RESULTS: We found that regulator of G protein signaling 1 (RGS1) expression was significantly elevated in Tregs compared to other CD4+ T cells in two independent public scRNA-seq datasets, and increased RGS1 predicted inferior clinical outcome of HCC patients. Multiplex immunofluorescence analysis supported that the higher expression of RGS1 in HCC Tregs in tumor tissue compared to it in adjacent tissue. Moreover, RGS1 expression in Tregs was positively correlated with the expression of marker genes of Tregs, C-X-C chemokine receptor 4 (CXCR4), and three CXCR4-dependent genes in both scRNA-seq and bulk RNA-seq data. We further identified that these three genes were selectively expressed in Tregs as compared to other CD4+ T cells. The activities of two transcription factors, recombination signal binding protein for immunoglobulin kappa J region (RBPJ) and yin yang 1 (YY1), were significantly different in HCC Tregs with RGS1 high and RGS1 low.
CONCLUSIONS: Our findings suggested that RGS1 may regulate Treg function possibly through CXCR4 signaling and RGS1 could be a potential target to improve responses for immunotherapy in HCC.

Heterotrimeric GTP-binding proteins comprised of Gα, Gβ and Gγ subunits are key regulators of a multitude of signaling pathways in eukaryotes. In plants, G-proteins are currently a focus of intense research due to their involvement in modulation of many agronomically important traits such as seed yield, organ size, abscisic acid (ABA)-dependent signaling and stress responses, plant defense responses, symbiosis and nitrogen use efficiency. The mechanistic details of G-protein biochemistry in modulating these processes in plants remain largely unknown. Although the core G-protein components and their activation/deactivation chemistries are broadly conserved throughout eukaryotic evolution, their regulation seems to have been rewired in plants to meet specific needs. Plant G-proteins may be spontaneously active and/or are regulated by phosphorylation-dependent changes, by the activity of lipid second messengers such as phospholipases, or may even have nucleotide-exchange independent regulation. Regardless of these deviations from the established norm, the biochemical properties of plant G-proteins are key to affecting plant phenotypes and responses. Detailed characterization of such activities, in vitro and in planta, will pave the way for precise manipulation of these proteins for future agricultural needs.