ECRG4: a new potential target in precision medicine

Comprehensive pan-cancer analysis of the C2ORF40 expression: Infiltration associations and prognostic implications

In recent years, C2ORF40 has been identified as a tumor suppressor gene with multiple functions, including roles in cell proliferation, migration, and senescence. To explore the role of the C2ORF40 gene in different tumors, we used multiple databases for analysis. Compared to adjacent normal tissues, C2ORF40 is downregulated in a variety of malignant tumors, including tumors such as breast cancer, colorectal cancer, bladder cancer, hepatocellular carcinoma and prostate cancer. Notably, low expression of the gene is significantly associated with poor overall survival and relapse-free survival rates. In specific cancers including colon cancer and prostate cancer, the expression of C2ORF40 is correlated with the infiltration of CAFs. C2ORF40 is also involved in biological processes such as cell apoptosis and regulation of protein stability. In conclusion, C2ORF40 can hold promise as a prognostic marker for pan-cancer analysis.

Complex and pleiotropic signaling pathways regulated by the secreted protein augurin

The secreted protein augurin, the product of the tumor suppressor gene Ecrg4, has been identified as a peptide hormone in the human proteome in 2007. Since then, a number of studies have been carried out to highlight its structure and processing and its potential roles in physiopathology. Although augurin has been shown to be implicated in a variety of processes, ranging from tumorigenesis, inflammation and infection to neural stem cell proliferation, hypothalamo-pituitary adrenal axis regulation and osteoblast differentiation, the molecular mechanisms of its biological effects and the signaling pathways it regulates are still poorly characterized. Here we provide a comprehensive overview of augurin-dependent signal transduction pathways. Because of their secreted nature and the potential to be manipulated pharmacologically, augurin and its derived peptides represent attractive targets for diagnostic development and discovery of new therapeutic agents for the human diseases resulting from the deregulation of the signaling cascades they modulate. From this perspective, the characterization of the precise nature of augurin derived peptides and the identification of the receptor(s) on the cell surface conveying augurin signaling to downstream effectors are crucial to develop agonists and antagonists for this protein. Video abstract.

Loss of Ecrg4 improves calcium oxalate nephropathy

Kidney stone is one of the most frequent urinary tract diseases, affecting 10% of the population and displaying a high recurrence rate. Kidney stones are the result of salt supersaturation, including calcium and oxalate. We have previously identified Esophageal cancer-related gene 4 (Ecrg4) as being modulated by hypercalciuria. Ecrg4 was initially described as a tumor suppressor gene in the esophagus. Lately, it was shown to be involved as well in apoptosis, cell senescence, cell migration, inflammation and cell responsiveness to chemotherapy. To the best of our knowledge, nothing is known about ECRG4's function in the renal tissue and its relationship with calciuria. We hypothesized that the increased expression of Ecrg4 mRNA is triggered by hypercalciuria and might modulate intratubular calcium-oxalate precipitation. In this study, we have first (i) validated the increased Ecrg4 mRNA in several types of hypercalciuric mouse models, then (ii) described the Ecrg4 mRNA expression along the nephron and (iii) assessed ECRG4's putative role in calcium oxalate nephropathy. For this, Ecrg4 KO mice were challenged with a kidney stone-inducing diet, rich in calcium and oxalate precursor. Taken together, our study demonstrates that Ecrg4's expression is restricted mainly to the distal part of the nephron and that the Ecrg4 KO mice develop less signs of tubular obstruction and less calcium-oxalate deposits. This promotes Ecrg4 as a modulator of renal crystallization and may open the way to new therapeutic possibilities against calcium oxalate nephropathy.

Single-cell multimodal analysis identifies common regulatory programs in synovial fibroblasts of rheumatoid arthritis patients and modeled TNF-driven arthritis

BACKGROUND

Synovial fibroblasts (SFs) are specialized cells of the synovium that provide nutrients and lubricants for the proper function of diarthrodial joints. Recent evidence appreciates the contribution of SF heterogeneity in arthritic pathologies. However, the normal SF profiles and the molecular networks that govern the transition from homeostatic to arthritic SF heterogeneity remain poorly defined.

METHODS

We applied a combined analysis of single-cell (sc) transcriptomes and epigenomes (scRNA-seq and scATAC-seq) to SFs derived from naïve and hTNFtg mice (mice that overexpress human TNF, a murine model for rheumatoid arthritis), by employing the Seurat and ArchR packages. To identify the cellular differentiation lineages, we conducted velocity and trajectory analysis by combining state-of-the-art algorithms including scVelo, Slingshot, and PAGA. We integrated the transcriptomic and epigenomic data to infer gene regulatory networks using ArchR and custom-implemented algorithms. We performed a canonical correlation analysis-based integration of murine data with publicly available datasets from SFs of rheumatoid arthritis patients and sought to identify conserved gene regulatory networks by utilizing the SCENIC algorithm in the human arthritic scRNA-seq atlas.

RESULTS

By comparing SFs from healthy and hTNFtg mice, we revealed seven homeostatic and two disease-specific subsets of SFs. In healthy synovium, SFs function towards chondro- and osteogenesis, tissue repair, and immune surveillance. The development of arthritis leads to shrinkage of homeostatic SFs and favors the emergence of SF profiles marked by Dkk3 and Lrrc15 expression, functioning towards enhanced inflammatory responses and matrix catabolic processes. Lineage inference analysis indicated that specific Thy1+ SFs at the root of trajectories lead to the intermediate Thy1+/Dkk3+/Lrrc15+ SF states and culminate in a destructive and inflammatory Thy1- SF identity. We further uncovered epigenetically primed gene programs driving the expansion of these arthritic SFs, regulated by NFkB and new candidates, such as Runx1. Cross-species analysis of human/mouse arthritic SF data determined conserved regulatory and transcriptional networks.

CONCLUSIONS

We revealed a dynamic SF landscape from health to arthritis providing a functional genomic blueprint to understand the joint pathophysiology and highlight the fibroblast-oriented therapeutic targets for combating chronic inflammatory and destructive arthritic disease.

Aberrant expression of the esophageal carcinoma related gene 4 as a prognostic signature for hepatocellular carcinoma

BACKGROUND AND OBJECTIVE

Hepatocellular carcinoma (HCC) is a lethal cancer with increasing incidence, yet the molecular biomarkers that have strong prognostic impact and also hold great therapeutic promise remain elusive.

METHODS

Data mining approaches with a set of publicly accessible databases and immunohistochemistry were used to provide a novel insight into the expression pattern and prognostic significance of the esophageal cancer-related gene (ECRG) family members in HCC.

RESULTS

We found that elevated mRNA expression levels of ECRG factors were correlated with better overall survival, relapse-free survival and progression-free survival rates in patients with HCC. Subgroup analyses showed significant associations between ECRG expression and survival outcome in select HCC patients. In addition, immunohistochemical and multivariate analysis confirmed increased ECRG4 expression as an independent prognostic indicator for survival.

CONCLUSIONS

Our data suggest that ECRG factors have significant impacts on the survival of HCC patients. The expression of ECRG factors may be involved in HCC progression and could serve as novel biomarkers for predicting more accurate prognosis.

ECRG4 acts as a tumor suppressor in nasopharyngeal carcinoma by suppressing the AKT/GSK3β/β-catenin signaling pathway

Nasopharyngeal carcinoma (NPC) is a malignant tumor with a poor prognosis. Studies have shown that esophageal carcinoma related gene 4 (ECRG4) is hypermethylated and significantly downregulated in NPC tissues. However, the role of ECRG4 in NPC, and in particular the underlying molecular mechanism, is largely unclear. In this study, using immunohistochemical staining of ECRG4 in NPC and normal specimens, we confirmed that ECRG4 was downregulated in human NPC tissues. In addition, various biological and molecular studies were carried out and the results showed that ECRG4 exerted anticancer effect in NPC, including inhibiting cell growth, migration, and invasion of NPC cells in vitro. Moreover, restoring ECRG4 expression suppressed the in vivo tumorigenesis of CNE2 cells. ECRG4 inhibited AKT/GSK3β/β-catenin signaling, as well as the downstream targets of β-catenin. LiCl treatment, which reduced GSK3β phosphorylation and upregulated β-catenin expression, restored the invasive ability of ECRG4-overexpressing NPC cells. Furthermore, we showed that the DNA methylation inhibitor 5-aza-dC reduced ECRG4 methylation and the invasive ability of negative control cells, but not that of ECRG4-overexpressing cells, suggesting that the inhibitory effect of 5-aza-dC depends on low expression of ECRG4. Collectively, our results demonstrated that ECRG4 downregulation contributed to NPC growth and invasion by activating AKT/GSK3β/β-catenin signaling pathway. ECRG4 could be a promising therapeutic target for the treatment of NPC.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s10616-022-00520-8.

Recent Advances in Engineered Noble Metal Nanomaterials as a Surface-Enhanced Raman Scattering Active Platform for Cancer Diagnostics

Recently, noble metal nanomaterials have been extensively studied in the fields of biosensing, environmental catalysis, and cancer diagnosis and treatment, due to their excellent electrical conductivity, high surface area, and individual physical and optical properties. Early research on the surface-enhanced Raman scattering (SERS) effect was focused on the cognition of the SERS phenomenon and enhancing its sensitivity for single-molecule detection. With the development of nanomaterials and nanotechnology, the advances and applications based on SERS substrates have been accelerated. Among them, noble metal nanomaterials are mainly used as SERS-active substrates to enhance SERS signals owing to their compelling surface plasmon resonance (SPR) properties. This review provides recent advances, perspectives, and challenges in SERS assays based on engineered noble metal nanomaterials for early cancer diagnosis.

Brain endothelial cells-derived extracellular vesicles overexpressing ECRG4 inhibit glioma proliferation through suppressing inflammation and angiogenesis

Esophageal cancer related gene-4 (ECRG4) has been shown to be a candidate tumor suppressor in many tumors, but its role in glioma remains poorly understood. This study aimed to explore whether extracellular vesicles (EVs) derived from brain endothelial cells which overexpressed ECRG4 have anti-tumor effect on gliomas in vivo and in vitro, as well as the possible mechanism. A constructed lentivirus expressing the ECRG4 gene was transfected into the hCMEC/D3 cell line. The EVs were isolated from the cells and characterized by Western blot with exosome markers of CD9, CD63, CD81, Alix. RT-PCR and Western blot were performed to verify ECRG4 expression. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and clone formation assays were applied to detect the proliferation of glioma cells incubated with EVs expressing the ECRG4 (ECRG4-exo). The level of inflammatory cytokines and angiogenesis related factors, including nuclear factor kappa-B (NF-κB), interleukin (IL)-1β, IL-6, IL-8, monocyte chemoattractant protein-1 (MCP-1), hypoxia-inducible factor 1-alpha (HIF-1α), vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor 2 (VEGFR2) levels were detected by ELISA. The T98G cell xenograft mouse model was established and treated with ECRG4-EV. The tumor volume and weight were recorded. p38-MAPK, p-p38-MAPK proteins were determined by Western blot in tumor tissues. As a result, EVs can be internalized into U87MG and T98G cells. ECRG4-EV inhibited U87MG and T98G cell proliferation. ECRG4-EV also inhibited the expression of factors involved in inflammation and angiogenesis. In addition, ECRG4-EVs suppressed tumor growth and decreased the production of inflammatory cytokines through inactivation of p38-MAPK signal pathway. In conclusion, ECRG4-EVsuppresses glioma proliferation through modulating the inflammation and angiogenesis.

C2orf40 inhibits hepatocellular carcinoma through interaction with UBR5

BACKGROUND AND AIM

Hepatocellular carcinoma (HCC) urgently needs a marker for early diagnosis and targeted treatment. C2orf40 has been identified as a tumor suppressor gene in many cancers. However, the precise role and regulatory mechanism by C2orf40 contribute to HCC remain elusive and merit exploration.

METHODS

Reverse-transcription PCR, quantitative real-time PCR, and methylation-specific PCR were used to detect expression and methylation of C2orf40 in HCC cell lines or tissues. The effects of C2orf40 in liver cancer cells were examined via colony formation, CCK8, transwell, and flow cytometric assays. The effect of C2orf40 on tumorigenesis in vivo was determined by xenografts and immunohistochemical analysis. Western blot, indirect immunofluorescence, Co-IP, and cycloheximide (CHX) were used to further investigate the potential mechanism of C2orf40.

RESULTS

The down-regulation of C2orf40 in hepatocellular cancer tissue samples is often related to the degree of methylation of its promoter CpG. The recovery of C2orf40 expression in HCC cell lines can induce G0/G1 phase arrest and apoptosis and also inhibit cell migration and invasion by reversing the epithelial-mesenchymal transition (EMT) process, both in vivo and in vitro. In addition, C2orf40 can increase the expression of p21 through interaction with UBR5.

CONCLUSIONS

Low expression levels of C2orf40 are related to the hypermethylation of its promoter. C2orf40 can inhibit HCC through UBR5-dependent or p53-independent mechanisms. C2orf40 may be a diagnostic biomarker and a potential therapeutic target in HCC.

ECRG4 Represses Cell Proliferation and Invasiveness via NFIC/OGN/NF-κB Signaling Pathway in Bladder Cancer

Bladder cancer (BCa) is a malignant tumor in the urinary system with high cancer-related mortality worldwide. However, the molecular mechanisms of many genes dysregulated in BCa are still unclear. Herein, we showed that esophageal cancer-related gene-4 (ECRG4), which is downregulated in BCa tissues and cell lines, has a positive correlation with osteoglycin (OGN). Further functional experimental studies suggested that both ECRG4 and OGN inhibit cell proliferation, migration, and invasion in BCa cells. Moreover, ECRG4 acts as a tumor repressor and promotes the expression of OGN via the upregulation of nuclear factor 1 C-type (NFIC), which can bind to the promoter region of OGN and regulate its transcription. Bioinformatics analysis revealed that NFIC is downregulated in BCa tissues and has a positive correlation with ECRG4 or OGN. Esophageal cancer-related gene-4 could positively regulate the protein levels of NFIC in BCa cells. In addition, we demonstrated for the first time that ECRG4 inhibits the nuclear factor (NF)-κB signaling pathway via the upregulation of OGN in BCa cells. Overall, these findings provide evidence that both ECRG4 and OGN function as tumor repressors and that overexpression of ECRG4 inhibits the NF-κB signaling pathway by promoting NFIC/OGN signaling in BCa cells. Our results reveal the molecular regulatory mechanisms of the ECRG4-mediated repression of the NFIC/OGN/NF-κB signaling pathway in BCa and provide potential biomarkers or therapeutic targets for BCa.

Open reading frame mining identifies a TLR4 binding domain in the primary sequence of ECRG4

The embedding of small peptide ligands within large inactive pre-pro-precursor proteins encoded by orphan open reading frames (ORFs) makes them difficult to identify and study. To address this problem, we generated oligonucleotide (< 100-400 base pair) combinatorial libraries from either the epidermal growth factor (EGF) ORF that encodes the > 1200 amino acid EGF precursor protein or the orphan ECRG4 ORF, that encodes a 148 amino acid Esophageal Cancer Related Gene 4 (ECRG4), a putative cytokine precursor protein of up to eight ligands. After phage display and 3-4 rounds of biopanning for phage internalization into prostate cancer epithelial cells, sequencing identified the 53-amino acid EGF ligand encoded by the 5' region of the EGF ORF and three distinct domains within the primary sequence of ECRG4: its membrane targeting hydrophobic signal peptide, an unanticipated amino terminus domain at ECRG437-63 and a C-terminus ECRG4133-148 domain. Using HEK-blue cells transfected with the innate immunity receptor complex, we show that both ECRG437-63 and ECRG4133-148 enter cells by interaction with the TLR4 immune complex but neither stimulate NFkB. Taken together, the results help establish that phage display can be used to identify cryptic domains within ORFs of the human secretome and identify a novel TLR4-targeted internalization domain in the amino terminus of ECRG4 that may contribute to its effects on cell migration, immune cell activation and tumor suppression.