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Radiation enteritis remains a major challenge for radiotherapy against abdominal and pelvic malignancies. Nevertheless, there is no approved effective therapy to alleviate irradiation (IR)-induced gastrointestinal (GI) toxicity. In the current study, Cannabidiol (CBD) was found to mitigate intestinal injury by GPX4-mediated ferroptosis resistance upon IR exposure. RNA-sequencing was employed to investigate the underlying mechanism involved in the radio-protective effect of CBD, wherein runt-related transcription factor 3 (RUNX3) and its target genes were changed significantly. Further experiment showed that the transactivation of GPX4 triggered by the direct binding of RUNX3 to its promoter region, or by stimulating the transcriptional activity of NF-κB via RUNX3-mediated LILRB3 upregulation was critical for the anti-ferroptotic effect of CBD upon IR injury. Specially, CBD was demonstrated to be a molecular glue skeleton facilitating the heterodimerization of RUNX3 with its transcriptional chaperone core-biding factor β (CBFβ) thereby promoting their nuclear localization and the subsequent transactivation of GPX4 and LILRB3. In short, our study provides an alternative strategy to counteract IR-induced enteritis during the radiotherapy on abdominal/pelvic neoplasms. [Display omitted] • CBD alleviated radiation enteritis via GPX4 mediated ferroptosis. • RUNX3 directly transactivates GPX4 thereby counteracting IR-induced ferroptosis. • LILRB3 transactivated by RUNX3 triggered by CBD conferred ferroptosis resistance. • LILRB3 transactivation by RUNX3 conferred to the nuclear translocation of NF-κB. • The interaction of CBFβ with RUNX3 facilitates the ferroptosis surveillance of CBD. The heterodimerization of RUNX3 with CBFβ stimulated by CBD treatment facilitated GPX4 and LILRB3 transactivation thereby conferring ferroptosis resistance upon IR exposure. [ABSTRACT FROM AUTHOR]

Abstract Background Diabetic nephropathy is a major secondary cause of end-stage renal disease. Apelin plays an important role in the development of DN. Understanding the exact mechanism of Apelin can help expand the means of treating DN. Methods Male C57BL/6 mice was used and STZ treatment was implemented for DN model establishment. Lentivirus systems including Lv-sh-RUNX3 and Lv-Apelin were obtained to knockdown RUNX3 and overexpress Apelin, respectively. A total of 36 mice were divided into 6 groups (n = 6 in each group): control, DN, DN + LV-Vector, DN + Lv-Apelin, DN + LV-Apelin + LV-sh-NC and DN + Lv-Apelin + Lv-sh-RUNX3 group. In vitro studies were performed using mesangial cells. Cell viability and proliferation was assessed through CCK8 and EDU analysis. Hematoxylin and eosin staining as well as Masson staining was implemented for histological evaluation. RT-qPCR was conducted for measuring relative mRNA levels, and protein expression was detected by western blotting. The interaction between SIRT1 and FOXO were verified by co-immunoprecipitations, and relations between RUNX3 and Apelin were demonstrated by dual luciferase report and chromatin immunoprecipitation. Results The DN group exhibited significantly lower Apelin expression compared to control (p

Aim: The impaired function of tubular mitochondria is critical in diabetic kidney disease (DKD) progression. RUNX3 is down‐regulated in DKD models. We intend to explore the effects of RUNX3 on mitochondrial dysfunction and renal tubule injury in DKD and related mechanisms. Methods: The development of diabetes models involved injecting mice with streptozotocin while treating HK‐2 cells with high glucose (HG). By using immunohistochemical techniques, the renal localizations of RUNX3 were identified. Levels of adenosine triphosphate (ATP), mitochondrial membrane potential, and biochemical index were detected by appropriate kits. Reactive oxygen species (ROS) generation was assessed with dihydroethidium and MitoSOX Red staining. Apoptosis was assessed by flow cytometry and TUNEL. RUNX3 ubiquitination was measured. Results: RUNX3 was mainly present in renal tubules. Overexpressing RUNX3 increased Mfn2, Mfn1, ATP levels, and mitochondrial membrane potential, reduced Drp1 and ROS levels and cell apoptosis, as well as Cyt‐C release into the cytoplasm. RUNX3 overexpression displayed a reduction in urinary albumin to creatinine ratio, Hemoglobin A1c, serum creatinine, and blood urea nitrogen. Overexpressing TLR4 attenuated the inhibitory effect of RUNX3 overexpression on mitochondrial dysfunction and cell apoptosis. HG promoted RUNX3 ubiquitination and SMURF2 expression. RUNX3 knockdown cancelled the inhibitory effect of SMURF2 on mitochondrial dysfunction and cell apoptosis. Conclusion: SMURF2 interference inhibits RUNX3 ubiquitination and TLR4/NF‐κB signalling pathway, thereby alleviating renal tubule injury. [ABSTRACT FROM AUTHOR]

Background: Diabetic nephropathy is a major secondary cause of end-stage renal disease. Apelin plays an important role in the development of DN. Understanding the exact mechanism of Apelin can help expand the means of treating DN. Methods: Male C57BL/6 mice was used and STZ treatment was implemented for DN model establishment. Lentivirus systems including Lv-sh-RUNX3 and Lv-Apelin were obtained to knockdown RUNX3 and overexpress Apelin, respectively. A total of 36 mice were divided into 6 groups (n = 6 in each group): control, DN, DN + LV-Vector, DN + Lv-Apelin, DN + LV-Apelin + LV-sh-NC and DN + Lv-Apelin + Lv-sh-RUNX3 group. In vitro studies were performed using mesangial cells. Cell viability and proliferation was assessed through CCK8 and EDU analysis. Hematoxylin and eosin staining as well as Masson staining was implemented for histological evaluation. RT-qPCR was conducted for measuring relative mRNA levels, and protein expression was detected by western blotting. The interaction between SIRT1 and FOXO were verified by co-immunoprecipitations, and relations between RUNX3 and Apelin were demonstrated by dual luciferase report and chromatin immunoprecipitation. Results: The DN group exhibited significantly lower Apelin expression compared to control (p < 0.05). Apelin overexpression markedly improved blood glucose, renal function indicators, ameliorated renal fibrosis and reduced fibrotic factor expression (p < 0.05) in the DN group, accompanied by elevated sirt1 levels and diminished acetylated FOXO1/FOXO3a (p < 0.05). However, RUNX3 knockdown combined with Apelin overexpression abrogated these beneficial effects, leading to impaired renal function, exacerbated fibrosis, increased fibrotic factor expression and acetylated FOXO1/FOXO3a versus Apelin overexpression alone (p < 0.05). In mesangial cells under high glucose, Apelin overexpression significantly inhibited cell proliferation and fibrotic factor production (p < 0.05). Conversely, RUNX3 interference enhanced cell proliferation and the secretion of fibrotic factors. (p < 0.05). Remarkably, combining Apelin overexpression with RUNX3 interference reversed the proliferation and fibrosis induced by RUNX3 interference (p < 0.05). Mechanistic studies revealed RUNX3 binds to the Apelin promoter, with the 467–489 bp site1 as the primary binding region, and SIRT1 physically interacts with FOXO1 and FOXO3a in mesangial cells. Conclusion: RUNX3 activated Apelin and regulated the SIRT1/FOXO signaling pathway, resulting in the suppressed cell proliferation and fibrosis in diabetic nephropathy. Apelin is a promising endogenous therapeutic target for anti-renal injury and anti-fibrosis in diabetic nephropathy. RUNX3 may serve as an endogenous intervention target for diseases related to Apelin deficiency. Highlight: 1. Apelin was significant downregulated in DN. 2. Apelin overexpression attenuates progression of DN. 3. Apelin inhibits mesangial cell proliferation and fibrosis via SIRT1/FOXO pathway. 4. RUNX3 transcriptionally upregulates Apelin expression. 5. RUNX3/Apelin axis regulates SIRT1/FOXO, mitigating DN progression. [ABSTRACT FROM AUTHOR]

Breast cancer severely affects women health. 70% of breast cancer are estrogen receptor positive. Breast cancer stem cells are a group of tumor with plasticity, causing tumor relapse and metastasis. RUNX3 is a tumor suppressor frequently inactivated in estrogen receptor positive breast cancer. However, the mechanism of how RUNX3 is involved in the regualation of cancer stem cell traits in estrogen receptor positive breast cancer remains elusive. In this study, we utilized cut-tag assay to investigate the binding profile RUNX3 in BT474 and T47D cell, and confirmed EXOSC4 as the bona-fide target of RUNX3; RUNX3 could bind to the promoter are of EXOSC4 to suppress its expression. Furthermore, EXOSC4 could increase the colony formation, cell invasion and mammosphere formation ability of breast cancer cells and upregulate the the expression of SOX2 and ALDH1. Consistent with these findings, EXOSC4 was associated with poorer survival for Luminal B/Her2 breast cancer patiens. At last, we confirmed that EXOSC4 mediated the tumor suppressive role of RUNX3 in breast cancer cells. In conclusion, we demonstrate that RUNX3 directly binds to the promoter region of EXOSC4, leading to the suppression of EXOSC4 expression and exerting a tumor-suppressive effect in estrogen receptor postivive breast cancer cells. [ABSTRACT FROM AUTHOR]

Objective: Researchers are actively investigating new diagnostic and prognostic biomarkers that offer improved sensitivity and specificity for systemic lupus erythematosus (SLE). One area of interest is DNA methylation changes. Previous studies have shown a connection between the RUNX3 gene dysfunction and SLE. In this study, the focus was on examining the methylation level of the RUNX3 promoter in peripheral blood mononuclear cells (PBMCs) of SLE patients and healthy individuals. Methods: A total of 80 individuals diagnosed with SLE from Iran, along with 77 healthy individuals, were included. The methylation levels of the RUNX3 gene in the extracted DNA were evaluated using the MethyQESD method. To determine the diagnostic effectiveness of the RUNX3 promoter methylation level, a receiver operating characteristic (ROC) curve was generated. Results: The methylation of the RUNX3 promoter was found to be significantly higher in patients with SLE compared to healthy individuals (p <.001). This difference in methylation levels was observed between SLE patients and healthy individuals and between SLE patients with renal involvement and those without renal involvement (86.29 ± 10.30 vs 40.28 ± 24.21, p <.001). ROC analyses revealed that the methylation level of the RUNX3 promoter had a diagnostic power of 0.769 [95% CI (0.681–0.814)] for SLE. Additionally, there was a positive correlation between the RUNX3 methylation level and levels of creatinine and C4. Conclusion: The findings of this study emphasize the potential use of RUNX3 methylation levels in PBMCs of SLE patients as biomarkers for diagnosing the disease, predicting renal damage, and assessing disease activity. [ABSTRACT FROM AUTHOR]

Long noncoding RNA MIR17HG was involved with the progression of non‐small‐cell lung cancer (NSCLC), but specific mechanisms of MIR17HG‐mediated immune escape of NSCLC cells were still unknown. The present study investigated the function of MIR17HG on regulatory T cell (Treg)‐mediated immune escape and the underlying mechanisms in NSCLC. Expression of MIR17HG and miR‐17‐5p in NSCLC tissue samples were detected using quantitative real‐time PCR (qRT‐PCR). A549 and H1299 cells were transfected with sh‐MIR17HG, miR‐17‐5p inhibitor, or sh‐MIR17HG + miR‐17‐5p inhibitor, followed by cocultured with Tregs. Cell proliferation was measured using 5‐ethynyl‐20‐deoxyuridine (Edu) staining assay and cell counting kit‐8 (CCK‐8) assay. Flow cytometry was used for determining positive numbers of FOXP3+CD4+/CD25+/CD8+ Tregs. Through subcutaneous injection with transfected A549 cells, a xenograft nude mouse model was established. Weights and volumes of xenograft tumors were evaluated. Additionally, the expressions of immune‐related factors including transforming growth factor beta (TGF‐β), vascular endothelial growth factor A (VEGF‐A), interleukin‐10 (IL‐10), IL‐4, and interferon‐gamma (IFN‐γ) in cultured cells, were evaluated by enzyme‐linked immunosorbent assay and western blot analysis. Then, miR‐17‐5p was decreased and MIR17HG was enhanced in both NSCLC tissues and cell lines. MIR17HG knockdown significantly suppressed cell proliferation, tumorigenicity, and immune capacity of Tregs in A549 and H1299 cells, whereas sh‐MIR17HG significantly reduced expression levels of VEGF‐A, TGF‐β, IL‐4, and IL‐10 but promoted the IFN‐γ level in vitro and in vivo. Moreover, downregulation of miR‐17‐5p significantly reversed the effects of sh‐MIR17HG. Additionally, we identified that runt‐ related transcription factor 3 (RUNX3) was a target of miR‐17‐5p, and sh‐MIR17HG and miR‐17‐5p mimics downregulated RUNX3 expression. In conclusion, downregulation of MIR17HG suppresses tumorigenicity and Treg‐mediated immune escape in NSCLC through downregulating the miR‐17‐5p/RUNX3 axis, indicating that this axis contains potential biomarkers for NSCLC. [ABSTRACT FROM AUTHOR]

Objectives: Previous reports have indicated that the methylation profile in peripheral blood mononuclear cells (PBMCs) in different genes and loci is altered in colorectal cancer (CRC). Regarding the high mortality rate and silent nature of CRC, screening and early detection can meaningfully reduce disease-related deaths. Therefore, for the first time, we aimed to evaluate the early non-invasive diagnosis of CRC via quantitative promoter methylation analysis of RUNX3 and RASSF1A genes in PBMCs. Materials and Methods: In the present study, we analyzed the methylation status of two important tumor suppressor genes including RUNX3 and RASSF1A in 70 CRC patients and 70 non-malignant subjects using methylation-quantification of endonuclease-resistant DNA (MethyQESD), and a bisulfite conversion-independent method. Results: RUNX3 was significantly hypermethylated in PBMCs of CRC patients compared to healthy controls(P < 0.001). By determining the efficient cutoff value, the sensitivity, and specificity of RUNX3 promoter methylation for CRC diagnosis reached 84.28% and 77.14%, respectively. The receiver operating characteristic (ROC) curve analyses demonstrated that RUNX3 promoter methylation has high accuracy (areas under the curve [AUC] = 0.840, P < 0.001) for discriminating CRC subjects from healthy individuals. Moreover, RUNX3 methylation levels in PBMCs progressively increased with the stage of the disease (P < 0.001). Although the amount of RASSF1A promoter methylation was not significantly different between CRC patients and controls as well as in different stages of the disease (P > 0.05). Conclusion: Our findings confirmed that PBMCs are reliable sources of methylation analysis for CRC screening, and RUNX3 promoter methylation can be used as a promising biomarker for early diagnosis of CRC. [ABSTRACT FROM AUTHOR]

We have recently reported that transcription factor Runx3 is required for pulmonary generation of CD8+ cytotoxic T lymphocytes (CTLs) that play a crucial role in the clearance of influenza A virus (IAV). To understand the underlying mechanisms, we determined the effects of Runx3 knockout (KO) on CD8+ T cell local expansion and phenotypes using an inducible general Runx3 KO mouse model. We found that in contrast to the lungs, Runx3 general KO promoted enlargement of lung-draining mediastinal lymph node (mLN) and enhanced CD8+ and CD4+ T cell expansion during H1N1 IAV infection. We further found that Runx3 deficiency greatly inhibited core 2 O-glycosylation of selectin ligand CD43 on activated CD8+ T cells but minimally affected the cell surface expression of CD43, activation markers (CD44 and CD69) and cell adhesion molecules (CD11a and CD54). Runx3 KO had a minor effect on lung effector CD8+ T cell death by IAV infection. Our findings indicate that Runx3 differently regulates CD8+ T cell expansion in mLNs and lungs by H1N1 IAV infection. Runx3 is required for CD43 core 2 O-glycosylation on activated CD8+ T cells, and the involved Runx3 signal pathway may mediate CD8+ T cell phenotype for pulmonary generation of CTLs. [ABSTRACT FROM AUTHOR]

CD4+CD8αα+ T cells in mouse and human small intestine epithelium are generated from MHC-II restricted mature CD4+ T cells by transcriptional reprogramming of lineage-specific nuclear factors, illustrating the remarkable plasticity of effector T cells in peripheral tissues. The concerted effort of multiple factors, such as microbial metabolites, cytokines, MHC-II, and other cell-surface molecules, drives the phenotypic and functional conversion of CD4+ T cells into CD4+CD8αα+ T cells. CD4+CD8αα+ T cells express markers and molecules of both CD4+ helper and CD8+ cytotoxic T cells, and display a wide range of immunoregulatory functions, ranging from intestinal epithelial cell cytolysis to immune suppression in the gut mucosa. The mammalian intestinal epithelium faces a unique immune environment because it serves as a barrier site against constantly invading pathogens, is exposed to the commensal microbiota, and needs to maintain immune quiescence but also remain immune competent. In response to these challenges, the IEL compartment harbors a series of immune effector cells. CD4+CD8αα+ IEL T cells, that are generated and reside in the SI epithelium, are proposed to play key roles in this process. Understanding the molecular mechanisms and pathways driving their generation can provide further insights into their role in gut immunity. The mammalian small intestine epithelium harbors a peculiar population of CD4+CD8αα+ T cells that are derived from mature CD4+ T cells through reprogramming of lineage-specific transcription factors. CD4+CD8αα+ T cells occupy a unique niche in T cell biology because they exhibit mixed phenotypes and functional characteristics of both CD4+ helper and CD8+ cytotoxic T cells. The molecular pathways driving their generation are not fully mapped. However, recent studies demonstrate the unique role of the commensal gut microbiota as well as distinct cytokine and chemokine requirements in the differentiation and survival of these cells. We review the established and newly identified factors involved in the generation of CD4+CD8αα+ intraepithelial lymphocytes (IELs) and place them in the context of the molecular machinery that drives their phenotypic and functional differentiation. [ABSTRACT FROM AUTHOR]

Abstract Lung adenocarcinoma (LUAD) is the most common pathological type of lung cancer, but the early diagnosis rate is low. The RNA-binding ubiquitin ligase MEX3C promotes tumorigenesis in several cancers but its mechanism of action in LUAD is unclear. In this study, the biological activity of MEX3C was assessed in LUAD. MEX3C and RUNX3 mRNA levels in the tissues of LUAD patients were determined using reverse transcription‑quantitative PCR. The involvement of MEX3C in the growth and metastasis of LUAD cells was measured by EdU assay, CCK-8, colony formation, Transwell assay, TUNEL, and flow cytometry. Expression of apoptosis and epithelial–mesenchymal transition related proteins were determined using western blotting analysis. LUAD cells transfected with si-MEX3C were administered to mice subcutaneously to monitor tumor progression and metastasis. We found that MEX3C is strongly upregulated in LUAD tissue sections, and involved in proliferation and migration. A549 and H1299 cells had significantly higher levels of MEX3C expression compared to control HBE cells. Knockdown of MEX3C dramatically decreased cell proliferation, migration, and invasion, and accelerated apoptosis. Mechanistically, we demonstrate MEX3C induces ubiquitylation and degradation of tumor suppressor RUNX3. Moreover, RUNX3 transcriptionally represses Suv39H1, as revealed by RNA pull-down and chromatin immunoprecipitation assays. The in vivo mice model demonstrated that knockdown of MEX3C reduced LUAD growth and metastasis significantly. Collectively, we reveal a novel MEX3C-RUNX3-Suv39H1 signaling axis driving LUAD pathogenesis. Targeting MEX3C may represent a promising therapeutic strategy against LUAD.

Abstract Background Intervertebral disc degeneration (IVDD) is the major cause of low-back pain. Histone deacetylase 9 (HDAC9) was dramatically decreased in the degenerative nucleus pulposus (NP) samples of patients with intervertebral disc degeneration (IVDD) according to bioinformatics analysis of Gene Expression Omnibus (GEO) GSE56081 dataset. This study aims to investigate the role of HDAC9 in IVDD progression. Methods The contribution of HDAC9 to the progression of IVDD was assessed using HDAC9 knockout (HDAC9KO) mice and NP-targeted HDAC9-overexpressing mice by IVD injection of adenovirus-mediated HDAC9 under a Col2a1 promoter. Magnetic resonance imaging (MRI) and histological analysis were used to examine the degeneration of IVD. NP cells were isolated from mice to investigate the effects of HDAC9 on apoptosis and viability. mRNA-seq and coimmunoprecipitation/mass spectrometry (co-IP/MS) analysis were used to analyze the HDAC9-regulated factors in the primary cultured NP cells. Results HDAC9 was statistically decreased in the NP tissues in aged mice. HDAC9KO mice spontaneously developed age-related IVDD compared with wild-type (HDAC9WT) mice. In addition, overexpression of HDAC9 in NP cells alleviated IVDD symptoms in a surgically-induced IVDD mouse model. In an in vitro assay, knockdown of HDAC9 inhibited cell viability and promoted cell apoptosis of NP cells, and HDAC9 overexpression had the opposite effects in NP cells isolated from HDAC9KO mice. Results of mRNA-seq and co-IP/MS analysis revealed the possible proteins and signaling pathways regulated by HDAC9 in NP cells. RUNX family transcription factor 3 (RUNX3) was screened out for further study, and RUNX3 was found to be deacetylated and stabilized by HDAC9. Knockdown of RUNX3 restored the effects of HDAC9 silencing on NP cells by inhibiting apoptosis and increasing viability. Conclusion Our results suggest that HDAC9 plays an important role in the development and progression of IVDD. It might be required to protect NP cells against the loss of cell viability and apoptosis by inhibiting RUNX3 acetylation and expression during IVDD. Together, our findings suggest that HDAC9 may be a potential therapeutic target in IVDD. Graphical Abstract

Lung adenocarcinoma (LUAD) is the most common pathological type of lung cancer, but the early diagnosis rate is low. The RNA-binding ubiquitin ligase MEX3C promotes tumorigenesis in several cancers but its mechanism of action in LUAD is unclear. In this study, the biological activity of MEX3C was assessed in LUAD. MEX3C and RUNX3 mRNA levels in the tissues of LUAD patients were determined using reverse transcription‑quantitative PCR. The involvement of MEX3C in the growth and metastasis of LUAD cells was measured by EdU assay, CCK-8, colony formation, Transwell assay, TUNEL, and flow cytometry. Expression of apoptosis and epithelial–mesenchymal transition related proteins were determined using western blotting analysis. LUAD cells transfected with si-MEX3C were administered to mice subcutaneously to monitor tumor progression and metastasis. We found that MEX3C is strongly upregulated in LUAD tissue sections, and involved in proliferation and migration. A549 and H1299 cells had significantly higher levels of MEX3C expression compared to control HBE cells. Knockdown of MEX3C dramatically decreased cell proliferation, migration, and invasion, and accelerated apoptosis. Mechanistically, we demonstrate MEX3C induces ubiquitylation and degradation of tumor suppressor RUNX3. Moreover, RUNX3 transcriptionally represses Suv39H1, as revealed by RNA pull-down and chromatin immunoprecipitation assays. The in vivo mice model demonstrated that knockdown of MEX3C reduced LUAD growth and metastasis significantly. Collectively, we reveal a novel MEX3C-RUNX3-Suv39H1 signaling axis driving LUAD pathogenesis. Targeting MEX3C may represent a promising therapeutic strategy against LUAD. [ABSTRACT FROM AUTHOR]

Kaposi’s sarcoma-associated herpesvirus (KSHV) belongs to the gamma herpesvirus family, which can cause human malignancies including Kaposi sarcoma, primary effusion lymphoma, and multicentric Castleman’s diseases. KSHV typically maintains a persistent latent infection within the host. However, after exposure to intracellular or extracellular stimuli, KSHV lytic replication can be reactivated. The reactivation process of KSHV triggers the innate immune response to limit viral replication. Here, we found that the transcriptional regulator RUNX3 is transcriptionally upregulated by the NF-κB signaling pathway in KSHV-infected SLK cells and B cells during KSHV reactivation. Notably, knockdown of RUNX3 significantly promotes viral lytic replication as well as the gene transcription of KSHV. Consistent with this finding, overexpression of RUNX3 impairs viral lytic replication. Mechanistically, RUNX3 binds to the KSHV genome and limits viral replication through transcriptional repression, which is related to its DNA- and ATP-binding ability. However, KSHV has also evolved corresponding strategies to antagonize this inhibition by using the viral protein RTA to target RUNX3 for ubiquitination and proteasomal degradation. Altogether, our study suggests that RUNX3, a novel host-restriction factor of KSHV that represses the transcription of viral genes, may serve as a potential target to restrict KSHV transmission and disease development. IMPORTANCE The reactivation of Kaposi’s sarcoma-associated herpesvirus (KSHV) from latent infection to lytic replication is important for persistent viral infection and tumorigenicity. However, reactivation is a complex event, and the regulatory mechanisms of this process are not fully elucidated. Our study revealed that the host RUNX3 is upregulated by the NF-κB signaling pathway during KSHV reactivation, which can repress the transcription of KSHV genes. At the late stage of lytic replication, KSHV utilizes a mechanism involving RTA to degrade RUNX3, thus evading host inhibition. This finding helps elucidate the regulatory mechanism of the KSHV life cycle and may provide new clues for the development of therapeutic strategies for KSHV-associated diseases. [ABSTRACT FROM AUTHOR]

Multiple sclerosis (MS) is a common and devastating chronic inflammatory disease of the CNS. CD4+ T cells are assumed to be the first to cross the blood–central nervous system (CNS) barrier and trigger local inflammation. Here, we explored how pathogenicity‐associated effector programs define CD4+ T cell subsets with brain‐homing ability in MS. Runx3‐ and Eomes‐, but not T‐bet‐expressing CD4+ memory cells were diminished in the blood of MS patients. This decline reversed following natalizumab treatment and was supported by a Runx3+Eomes+T‐bet− enrichment in cerebrospinal fluid samples of treatment‐naïve MS patients. This transcription factor profile was associated with high granzyme K (GZMK) and CCR5 levels and was most prominent in Th17.1 cells (CCR6+CXCR3+CCR4−/dim). Previously published CD28− CD4 T cells were characterized by a Runx3+Eomes−T‐bet+ phenotype that coincided with intermediate CCR5 and a higher granzyme B (GZMB) and perforin expression, indicating the presence of two separate subsets. Under steady‐state conditions, granzyme Khigh Th17.1 cells spontaneously passed the blood–brain barrier in vitro. This was only found for other subsets including CD28− cells when using inflamed barriers. Altogether, CD4+ T cells contain small fractions with separate pathogenic features, of which Th17.1 seems to breach the blood–brain barrier as a possible early event in MS. [ABSTRACT FROM AUTHOR]

Introduction: We have previously observed phenotypic and developmental changes upon the ectopic expression of the RUNX3 or the ZBTB46 transcription factors in mouse embryonic stem cell (ESC) derived progenitors. In this study, we evaluated the gene expression profiles of the RUNX3- and the ZBTB46-instructed murine ESCs with RNA-seq testing two next-generation sequencing technologies. Methods: We compared the DNA nanoball-based DNBSEQ G400 sequencer (MGI) with the bridge-PCR-based NextSeq 500 instrument (Illumina) for RNA sequencing. Moreover, we also compared two types of MGI sequencing reagents (Standard versus Hot-massive parallel sequencing (MPS)) with the DNBSEQ G400. Results: We observed that both sequencing platforms showed comparable levels of quality, sequencing uniformity, and gene expression profiles. For example, highly overlapping RUNX3- and ZBTB46-regulated gene lists were obtained from both sequencing datasets. Moreover, we observed that the Standard and the Hot-MPS-derived RUNX3- and ZBTB46-regulated gene lists were also considerably overlapped. This transcriptome analysis also helped us to identify differently expressed genes in the presence of the transgenic RUNX3 or ZBTB46. For example, we found that Gzmb, Gzmd, Gzme, Gdf6, and Ccr7 genes were robustly upregulated upon the forced expression of Runx3; on the other hand, Gpx2, Tdpoz4, and Arg2 were induced alongside the ectopic expression of Zbtb46. Discussion: Similar gene expression profile and greatly overlapping RUNX3- and ZBTB46-regulated gene sets were detected with both DNA sequencing platforms. Our analyses demonstrate that both sequencing technologies are suitable for transcriptome profiling and target gene selection. These findings suggest that DNBSEQ G400 represents a cost-effective alternative sequencing platform for gene expression monitoring. Moreover, this analysis provides a resource for exploration of the RUNX3- and ZBTB46-dependent gene regulatory networks. [ABSTRACT FROM AUTHOR]

Breast cancer (BC) ranks as the most prevalent gynecologic tumor globally. Abnormal expression of miRNAs is concerned with the development of cancers such as BC. However, little is known about the role of miR‐600 in BC. This work aimed to explore the role of miR‐600 in the malignant progression and sorafenib sensitivity of BC cells. Expression and interaction of miR‐600/EZH2/RUNX3 were analyzed by bioinformatics. qRT‐PCR was utilized to assay RNA expression of miR‐600 and mRNA expression of EZH2/RUNX3. The binding relationship between miR‐600 and EZH2 was tested by dual luciferase assay and RNA immunoprecipitation (RIP). The effects of miR‐600/EZH2/RUNX3 axis on the malignant behavior and sorafenib sensitivity of BC cells were detected by CCK‐8 and colony formation assay. Low expression of miR‐600 and RUNX3 in BC was found by bioinformatics and molecular assays. High expression of EZH2 in BC was negatively correlated with RUVX3. Dual luciferase assay and RIP demonstrated that MiR‐600 could bind to EZH2. Cell assays displayed that miR‐600 knockdown could foster the malignant progression of BC cells and reduce the sensitivity of BC cells to sorafenib. EZH2 knockdown or RUNX3 overexpression could offset the effect of miR‐600 inhibitor on the malignant behavior and sorafenib sensitivity of BC cells. MiR‐600 can hinder the malignant behavior of BC cells and foster sensitivity of BC cells to sorafenib via EZH2/RUNX3 axis, exhibiting the miR‐600/EZH2/RUNX3 axis as a feasible therapeutic target for BC patients. [ABSTRACT FROM AUTHOR]

Background: Intervertebral disc degeneration (IVDD) is the major cause of low-back pain. Histone deacetylase 9 (HDAC9) was dramatically decreased in the degenerative nucleus pulposus (NP) samples of patients with intervertebral disc degeneration (IVDD) according to bioinformatics analysis of Gene Expression Omnibus (GEO) GSE56081 dataset. This study aims to investigate the role of HDAC9 in IVDD progression. Methods: The contribution of HDAC9 to the progression of IVDD was assessed using HDAC9 knockout (HDAC9KO) mice and NP-targeted HDAC9-overexpressing mice by IVD injection of adenovirus-mediated HDAC9 under a Col2a1 promoter. Magnetic resonance imaging (MRI) and histological analysis were used to examine the degeneration of IVD. NP cells were isolated from mice to investigate the effects of HDAC9 on apoptosis and viability. mRNA-seq and coimmunoprecipitation/mass spectrometry (co-IP/MS) analysis were used to analyze the HDAC9-regulated factors in the primary cultured NP cells. Results: HDAC9 was statistically decreased in the NP tissues in aged mice. HDAC9KO mice spontaneously developed age-related IVDD compared with wild-type (HDAC9WT) mice. In addition, overexpression of HDAC9 in NP cells alleviated IVDD symptoms in a surgically-induced IVDD mouse model. In an in vitro assay, knockdown of HDAC9 inhibited cell viability and promoted cell apoptosis of NP cells, and HDAC9 overexpression had the opposite effects in NP cells isolated from HDAC9KO mice. Results of mRNA-seq and co-IP/MS analysis revealed the possible proteins and signaling pathways regulated by HDAC9 in NP cells. RUNX family transcription factor 3 (RUNX3) was screened out for further study, and RUNX3 was found to be deacetylated and stabilized by HDAC9. Knockdown of RUNX3 restored the effects of HDAC9 silencing on NP cells by inhibiting apoptosis and increasing viability. Conclusion: Our results suggest that HDAC9 plays an important role in the development and progression of IVDD. It might be required to protect NP cells against the loss of cell viability and apoptosis by inhibiting RUNX3 acetylation and expression during IVDD. Together, our findings suggest that HDAC9 may be a potential therapeutic target in IVDD. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC), also known as colon cancer, is the third most common cancer and the fourth most cause of cancer-related death in the world. CRC can be classified into two major subtypes, including microsatellite instability (MSI) and microsatellite stability (MSS), which showed different characteristics in immunotherapy. Low sensitivity of diagnostic biomarkers and metastasis are still the principal cause of mortality, especially in MSI. Here, applying computational programs, we identified recurring expression programs based on single cell RNA sequencing (scRNA-Seq) data of CRC cell lines. Notably, three MSI specific recurring modules were identified by non-negative matrix factorization (NMF). High NMF score genes enriched in the function of metabolism and inflammatory response. Focusing on top specific active transcription factor (TF), RUNX3 (Runt-related transcription factor 3), our results suggest that T cell infiltration was increased in RUNX3 high MSI CRC samples. Unbiased Gene Set Enrichment Analysis (GSEA) showed that RUNX3 was strongly associated with immune and metastasis related functions, such as Interferon Gamma (IFN-γ) and EPITHELIAL MESENCHYMAL TRANSITION (EMT). In addition, RUNX3 shows specific highly activated at epigenetic level in MSI compared with other gastrointestinal carcinomas. Positive correlation between RUNX3 and most immune checkpoints further confirmed RUNX3 might have crucial roles in MSI cancer progression and immunotherapy. Taken together, these results indicate significant tumor heterogeneity of two CRC subtypes at single-cell level and epigenetic modification level. These results also linked transcriptional dysregulation with immune infiltration at single-cell level in MSI, which may advance the application of scRNA-Seq technology in immunotherapy and contribute to developing novel biomarkers of this malignancy.

Abstract Background Prostate cancer (PCa) is currently acknowledged as the second most widespread cancer among men worldwide. Yet, the lack of dependable diagnostic biomarkers and therapeutic targets has presented considerable hurdles to the progression of prostate cancer treatment. Circular RNAs are implicated in the pathogenesis of numerous diseases, positioning them as promising biomarkers for diverse medical conditions. This study aims to uncover a specific circRNA that could serve as a diagnostic and therapeutic target for detecting and treating PCa. Methods The change of circTENM3 expression levels in PCa was detected by qPCR. CCK8 assays, EdU assays, Scratch assay and Transwell migration assay conducted to detect the role of circTENM3 in PCa cells in vitro. RIP assay, RNA-pull down and luciferase reporter assay were performed to explore the mechanism of circTENM3. Gain-of-function analysis was performed to reveal the function of circTENM3 in PCa in vivo. Results The results revealed that the expression level of circTENM3 was significantly down-regulated in PCa. CircTENM3 overexpression alleviated the progression of PCa in vitro. Mechanistically, circTENM3 enhanced RUNX3 levels via miR-558 sponge. Gain-of-function analysis determined that circTENM3 overexpression could inhibit PCa progression in vitro. Conclusions Our research offers profound insights into the protective role played by circTENM3 in PCa. CircTENM3 operates as a sponge for miR-558, thereby triggering the elevation of RUNX3 expression, which subsequently curbs the progression of PCa.

Abstract Background Cancer‐associated fibroblasts (CAFs) are a major stromal component of human breast cancers and often promote tumor proliferation, progression and malignancy. We previously established an experimental CAF (exp‐CAF) cell line equipped with a potent tumor‐promoting ability. It was generated through prolonged incubation of immortalized human mammary fibroblasts with human breast cancer cells in a tumor xenograft mouse model. Results Herein, we found that the exp‐CAFs highly express Runt‐related transcription factor 3 (RUNX3), while counterpart fibroblasts do not. In breast cancer patients, the proportion of RUNX3‐positive stromal fibroblast‐like cells tends to be higher in cancerous regions than in non‐cancerous regions. These findings suggest an association of RUNX3 with CAF characteristics in human breast cancers. To investigate the functional role of RUNX3 in CAFs, the exp‐CAFs with or without shRNA‐directed knockdown of RUNX3 were implanted with breast cancer cells subcutaneously in immunodeficient mice. Comparison of the resulting xenograft tumors revealed that tumor growth was significantly attenuated when RUNX3 expression was suppressed in the fibroblasts. Consistently, Ki‐67 and CD31 immunohistochemical staining of the tumor sections indicated reduction of cancer cell proliferation and microvessel formation in the tumors formed with the RUNX3‐suppressed exp‐CAFs. Conclusion These results suggest that increased RUNX3 expression could contribute to the tumor‐promoting ability of CAFs through mediating cancer cell growth and neoangiogenesis in human breast tumors.

Abstract Background Radioimmunotherapy with cetuximab and conjugates with various radioisotopes is a feasible treatment option for different tumor models. Scandium-47 (47Sc), one of several β−-particle-emitting radioisotopes, displays favorable physical and chemical properties for conjugation to monoclonal antibodies. However, the therapeutic efficacy of 47Sc in preclinical and clinical studies is largely unknown. Given that intrinsic alterations in tumors greatly contribute to resistance to anti-epidermal growth factor receptor (EGFR)-targeted therapy, research on overcoming resistance to radioimmunotherapy using cetuximab is required. Methods 47Sc was produced by irradiation of a CaCO3 target at the HANARO research reactor in KAERI (Korea Atomic Energy Research Institute) and prepared by chromatographic separation of the irradiated target. Cetuximab was conjugated with 47Sc using the bifunctional chelating agent DTPA. Radiochemical purity was determined using instant thin-layer chromatography. The immunoreactivity of 47Sc-DTPA-cetuximab was evaluated using the Lindmo method and an in vitro cell-binding assay. The inhibitory effects of cetuximab and 47Sc-DTPA-cetuximab were confirmed using cell growth inhibition and BrdU cell proliferation assays. Differences in protein expression levels between cetuximab- and 47Sc-DTPA-cetuximab-treated cells were confirmed using western blotting. Complex formation between RUNX3 and DNA repair components was confirmed using immunoprecipitation and western blotting. Results Cetuximab induces cell cycle arrest and cell death in EGFR-overexpressing NSCLC cells. Radiolabeling of cetuximab with 47Sc led to increased therapeutic efficacy relative to cetuximab alone. Application of 47Sc-DTPA-cetuximab induced DNA damage responses, and activation of RUNX3 significantly enhanced the therapeutic efficacy of 47Sc-DTPA-cetuximab. RUNX3 mediated susceptibility to EGFR-targeted NSCLC therapy using 47Sc-DTPA-cetuximab via interaction with components of the DNA damage and repair machinery. Conclusions 47Sc-DTPA-cetuximab promoted cell death in EGFR-overexpressing NSCLC cells by targeting EGFR and inducing DNA damage as a result of β irradiation emitted from the conjugated 47Sc. Activation of RUNX3 played a key role in DNA damage and repair processes in response to the ionizing radiation and inhibited cell growth, thus leading to more effective tumor suppression. RUNX3 can potentially moderate susceptibility to 47Sc-conjugated cetuximab by modulating DNA damage and repair process mechanisms.

Introduction: We have previously observed phenotypic and developmental changes upon the ectopic expression of the RUNX3 or the ZBTB46 transcription factors in mouse embryonic stem cell (ESC) derived progenitors. In this study, we evaluated the gene expression profiles of the RUNX3- and the ZBTB46-instructed murine ESCs with RNA-seq testing two next-generation sequencing technologies.Methods: We compared the DNA nanoball-based DNBSEQ G400 sequencer (MGI) with the bridge-PCR-based NextSeq 500 instrument (Illumina) for RNA sequencing. Moreover, we also compared two types of MGI sequencing reagents (Standard versus Hot-massive parallel sequencing (MPS)) with the DNBSEQ G400.Results: We observed that both sequencing platforms showed comparable levels of quality, sequencing uniformity, and gene expression profiles. For example, highly overlapping RUNX3- and ZBTB46-regulated gene lists were obtained from both sequencing datasets. Moreover, we observed that the Standard and the Hot-MPS-derived RUNX3- and ZBTB46-regulated gene lists were also considerably overlapped. This transcriptome analysis also helped us to identify differently expressed genes in the presence of the transgenic RUNX3 or ZBTB46. For example, we found that Gzmb, Gzmd, Gzme, Gdf6, and Ccr7 genes were robustly upregulated upon the forced expression of Runx3; on the other hand, Gpx2, Tdpoz4, and Arg2 were induced alongside the ectopic expression of Zbtb46.Discussion: Similar gene expression profile and greatly overlapping RUNX3- and ZBTB46-regulated gene sets were detected with both DNA sequencing platforms. Our analyses demonstrate that both sequencing technologies are suitable for transcriptome profiling and target gene selection. These findings suggest that DNBSEQ G400 represents a cost-effective alternative sequencing platform for gene expression monitoring. Moreover, this analysis provides a resource for exploration of the RUNX3- and ZBTB46-dependent gene regulatory networks.

Background: Prostate cancer (PCa) is currently acknowledged as the second most widespread cancer among men worldwide. Yet, the lack of dependable diagnostic biomarkers and therapeutic targets has presented considerable hurdles to the progression of prostate cancer treatment. Circular RNAs are implicated in the pathogenesis of numerous diseases, positioning them as promising biomarkers for diverse medical conditions. This study aims to uncover a specific circRNA that could serve as a diagnostic and therapeutic target for detecting and treating PCa. Methods: The change of circTENM3 expression levels in PCa was detected by qPCR. CCK8 assays, EdU assays, Scratch assay and Transwell migration assay conducted to detect the role of circTENM3 in PCa cells in vitro. RIP assay, RNA-pull down and luciferase reporter assay were performed to explore the mechanism of circTENM3. Gain-of-function analysis was performed to reveal the function of circTENM3 in PCa in vivo. Results: The results revealed that the expression level of circTENM3 was significantly down-regulated in PCa. CircTENM3 overexpression alleviated the progression of PCa in vitro. Mechanistically, circTENM3 enhanced RUNX3 levels via miR-558 sponge. Gain-of-function analysis determined that circTENM3 overexpression could inhibit PCa progression in vitro. Conclusions: Our research offers profound insights into the protective role played by circTENM3 in PCa. CircTENM3 operates as a sponge for miR-558, thereby triggering the elevation of RUNX3 expression, which subsequently curbs the progression of PCa. [ABSTRACT FROM AUTHOR]

Long‐term abuse of methamphetamine (MA) can cause lung toxicity. Intercellular communication between macrophages and alveolar epithelial cells (AECs) is critical for maintaining lung homeostasis. Microvesicles (MVs) are an important medium of intercellular communication. However, the mechanism of macrophage MVs (MMVs) in MA‐induced chronic lung injury remains unclear. This study aimed to investigate if MA can augment the activity of MMVs and if circ_YTHDF2 is a key factor in MMV‐mediated macrophage–AEC communication, and to explore the mechanism of MMV‐derived circ_YTHDF2 in MA‐induced chronic lung injury. MA elevated peak velocity of the pulmonary artery and pulmonary artery accelerate time, reduced the number of alveolar sacs, thickened the alveolar septum, and accelerated the release of MMVs and the uptake of MMVs by AECs. Circ_YTHDF2 was downregulated in lung and MMVs induced by MA. The immune factors in MMVs were increased by si‐circ_YTHDF. Circ_YTHDF2 knockdown in MMVs induced inflammation and remodelling in the internalised AECs by MMVs, which was reversed by circ_YTHDF2 overexpression in MMVs. Circ_YTHDF2 bound specifically to and sponged miRNA‐145‐5p. Runt‐related transcription factor 3 (RUNX3) was identified as potential target of miR‐145‐5p. RUNX3 targeted zinc finger E‐box‐binding homeobox 1 (ZEB1)‐related inflammation and EMT of AECs. In vivo, circ_YTHDF2 overexpression‐MMVs attenuated MA‐induced lung inflammation and remodelling by the circ_YTHDF2–miRNA‐145‐5p–RUNX3 axis. Therefore, MA abuse can induce pulmonary dysfunction and alveolus injury. The immunoactivity of MMVs is regulated by circ_YTHDF2. Circ_YTHDF2 in MMVs is the key to communication between macrophages and AECs. Circ_YTHDF2 sponges miR‐145‐5p targeting RUNX3 to participate in ZEB1‐related inflammation and remodelling of AECs. MMV‐derived circ_YTHDF2 would be an important therapeutic target for MA‐induced chronic lung injury. Key points: Methamphetamine (MA) abuse induces pulmonary dysfunction and alveoli injury.The immunoactivity of macrophage microvesicles (MMVs) is regulated by circ_YTHDF2.Circ_YTHDF2 in MMVs is the key to MMV‐mediated intercellular communication between macrophages and alveolar epithelial cells.Circ_YTHDF2 sponges miR‐145‐5p targeting runt‐related transcription factor 3 (RUNX3) to participate in zinc finger E‐box‐binding homeobox 1 (ZEB1)‐related inflammation and remodelling.MMV‐derived circ_YTHDF2 would be an important therapeutic target for MA‐induced chronic lung injury. [ABSTRACT FROM AUTHOR]

The protein PIAS1 functions as a type of ubiquitin-protease, which is known to play an important regulatory role in various diseases, including cardiovascular diseases and cancers. Its mechanism of action primarily revolves around regulating the transcription, translation, and modification of target proteins. This study investigates role and mechanism of PIAS1 in the RUNX3/TSP-1 axis and confirms its therapeutic effects on diabetes-related complications in animal models. A diabetic vascular injury was induced in human umbilical vein endothelial cells (HUVECs) by stimulation with H2O2 and advanced glycation end product (AGE), and a streptozotocin (STZ)-induced mouse model of diabetes was constructed, followed by detection of endogenous PIAS1 expression and SUMOylation level of RUNX3. Effects of PIAS1 concerning RUNX3 and TSP-1 on the HUVEC apoptosis and inflammation were evaluated using the ectopic expression experiments. Down-regulated PIAS1 expression and SUMOylation level of RUNX3 were identified in the H2O2- and AGE-induced HUVEC model of diabetic vascular injury and STZ-induced mouse models of diabetes. PIAS1 promoted the SUMOylation of RUNX3 at the K148 site of RUNX3. PIAS1-mediated SUMOylation of RUNX3 reduced RUNX3 transactivation activity, weakened the binding of RUNX3 to the promoter region of TSP-1, and caused downregulation of TSP-1 expression. PIASI decreased the expression of TSP-1 by inhibiting H2O2- and AGE-induced RUNX3 de-SUMOylation, thereby arresting the inflammatory response and apoptosis of HUVECs. Besides, PIAS1 reduced vascular endothelial injury and atherosclerotic plaque formation in mouse models of diabetes by inhibiting the RUNX3/TSP-1 axis. Our study proved that PIAS1 suppressed vascular endothelial injury and atherosclerotic plaque formation in mouse models of diabetes via the RUNX3/TSP-1 axis. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to assess the clinical significance of RUNX3 gene hypermethylation in the pathogenetic mechanisms of breast cancer in women, taking into account its cohypermethylation with the BRCA1 gene. Methods: This study included 74 women with newly diagnosed breast cancer (samples from female primary breast carcinomas and paired peripheral blood samples) and 62 women without oncological pathology—control group (peripheral blood samples). Epigenetic testing for hypermethylation status studying was performed in all samples on freshly collected material with the addition of a preservative before the storage and DNA isolation. Results: Hypermethylation of the RUNX3 gene promoter region was detected in 71.6% samples of breast cancer tissue and in 35.13% samples of blood. The RUNX3 gene promoter region hypermethylation was significantly higher among breast cancer patients compared to the control group. The frequency of cohypermethylation in RUNX3 and BRCA1 genes was significantly increased in breast cancer tissues compared to the blood of patients. Conclusion: A significantly increased frequency of the hypermethylation of the RUNX3 gene promoter region and its cohypermethylation with the BRCA1 gene promoter region was found in tumor tissue and blood samples from patients with breast cancer, in contrast to the control group. The identified differences indicate the importance of further investigations of suppressor genes cohypermethylation in patients with breast cancer. Further large-scale studies are needed to find out whether the detected hypermethylation and cohypermethylation of the RUNX3 gene promoter region will have an impact on the treatment strategy in patients. [ABSTRACT FROM AUTHOR]

Background: Cancer‐associated fibroblasts (CAFs) are a major stromal component of human breast cancers and often promote tumor proliferation, progression and malignancy. We previously established an experimental CAF (exp‐CAF) cell line equipped with a potent tumor‐promoting ability. It was generated through prolonged incubation of immortalized human mammary fibroblasts with human breast cancer cells in a tumor xenograft mouse model. Results: Herein, we found that the exp‐CAFs highly express Runt‐related transcription factor 3 (RUNX3), while counterpart fibroblasts do not. In breast cancer patients, the proportion of RUNX3‐positive stromal fibroblast‐like cells tends to be higher in cancerous regions than in non‐cancerous regions. These findings suggest an association of RUNX3 with CAF characteristics in human breast cancers. To investigate the functional role of RUNX3 in CAFs, the exp‐CAFs with or without shRNA‐directed knockdown of RUNX3 were implanted with breast cancer cells subcutaneously in immunodeficient mice. Comparison of the resulting xenograft tumors revealed that tumor growth was significantly attenuated when RUNX3 expression was suppressed in the fibroblasts. Consistently, Ki‐67 and CD31 immunohistochemical staining of the tumor sections indicated reduction of cancer cell proliferation and microvessel formation in the tumors formed with the RUNX3‐suppressed exp‐CAFs. Conclusion: These results suggest that increased RUNX3 expression could contribute to the tumor‐promoting ability of CAFs through mediating cancer cell growth and neoangiogenesis in human breast tumors. [ABSTRACT FROM AUTHOR]

Transcription factors are key components in gene expression and are associated with various diseases. Transcription factors maintain the stability of gene transcription and cell function. Among the transcription factors, the Runt-related transcription factor (RUNX) family regulates growth and development in a tissue-specific manner and is involved in tumorigenesis. The function of an important member of the RUNX family, RUNX3, was shown to be closely related to its subcellular localization. Normally, RUNX3 promotes or represses gene transcription in the nucleus; however, when RUNX3 is restricted in the cytoplasm, RUNX3 fails to function and only has a minor effect o gene expression. Hence, the risk of tumorigenesis cannot simply be equated with the level of RUNX3 expression, which makes the diagnosis and treatment of cancer more complicated. The cytoplasmic localization of RUNX3 has been shown to be associated with a variety of tumors. Herein we have summarized the current information on RUNX3 mis-localization and RUNX3 promotion of tumorigenesis, thus providing new insight for future investigations to elucidate the mechanisms by which RUNX3 regulates tumorigenesis.

Abstract Background Extranodal natural killer/T-cell lymphoma (NKTL) is an aggressive type of non-Hodgkin lymphoma with dismal outcome. A better understanding of disease biology and key oncogenic process is necessary for the development of targeted therapy. Super-enhancers (SEs) have been shown to drive pivotal oncogenes in various malignancies. However, the landscape of SEs and SE-associated oncogenes remain elusive in NKTL. Methods We used Nano-ChIP-seq of the active enhancer marker histone H3 lysine 27 acetylation (H3K27ac) to profile unique SEs NKTL primary tumor samples. Integrative analysis of RNA-seq and survival data further pinned down high value, novel SE oncogenes. We utilized shRNA knockdown, CRISPR-dCas9, luciferase reporter assay, ChIP-PCR to investigate the regulation of transcription factor (TF) on SE oncogenes. Multi-color immunofluorescence (mIF) staining was performed on an independent cohort of clinical samples. Various function experiments were performed to evaluate the effects of TOX2 on the malignancy of NKTL in vitro and in vivo. Results SE landscape was substantially different in NKTL samples in comparison with normal tonsils. Several SEs at key transcriptional factor (TF) genes, including TOX2, TBX21(T-bet), EOMES, RUNX2, and ID2, were identified. We confirmed that TOX2 was aberrantly overexpressed in NKTL relative to normal NK cells and high expression of TOX2 was associated with worse survival. Modulation of TOX2 expression by shRNA, CRISPR-dCas9 interference of SE function impacted on cell proliferation, survival and colony formation ability of NKTL cells. Mechanistically, we found that RUNX3 regulates TOX2 transcription by binding to the active elements of its SE. Silencing TOX2 also impaired tumor formation of NKTL cells in vivo. Metastasis-associated phosphatase PRL-3 has been identified and validated as a key downstream effector of TOX2-mediated oncogenesis. Conclusions Our integrative SE profiling strategy revealed the landscape of SEs, novel targets and insights into molecular pathogenesis of NKTL. The RUNX3-TOX2-SE-TOX2-PRL-3 regulatory pathway may represent a hallmark of NKTL biology. Targeting TOX2 could be a valuable therapeutic intervene for NKTL patients and warrants further study in clinic.

We have recently reported that transcription factor Runx3 is required for pulmonary generation of CD8+ cytotoxic T lymphocytes (CTLs) that play a crucial role in the clearance of influenza A virus (IAV). To understand the underlying mechanisms, we determined the effects of Runx3 knockout (KO) on CD8+ T cell local expansion and phenotypes using an inducible general Runx3 KO mouse model. We found that in contrast to the lungs, Runx3 general KO promoted enlargement of lung-draining mediastinal lymph node (mLN) and enhanced CD8+ and CD4+ T cell expansion during H1N1 IAV infection. We further found that Runx3 deficiency greatly inhibited core 2 O-glycosylation of selectin ligand CD43 on activated CD8+ T cells but minimally affected the cell surface expression of CD43, activation markers (CD44 and CD69) and cell adhesion molecules (CD11a and CD54). Runx3 KO had a minor effect on lung effector CD8+ T cell death by IAV infection. Our findings indicate that Runx3 differently regulates CD8+ T cell expansion in mLNs and lungs by H1N1 IAV infection. Runx3 is required for CD43 core 2 O-glycosylation on activated CD8+ T cells, and the involved Runx3 signal pathway may mediate CD8+ T cell phenotype for pulmonary generation of CTLs.

This study aimed to determine the expression levels of runt-related transcription factor 3 (RUNX3) and caudal-related homeobox 2 (CDX2) in patients with chronic gastritis, intestinal metaplasia, atypical hyperplasia, and gastric cancer (GC). To analyze the overexpression of CDX2 and the effects of resveratrol (Res) on MKN7 and TMK1 cells, immunohistochemical staining was performed to determine the protein expression levels in tissue samples. The biological activity of MKN7 and TMK1 cells was determined. Relative mRNA and protein expression levels were also determined. RUNX3 expression was positively correlated with CDX2 expression and negatively correlated with β-catenin and transcription factor 4 (TCF-4) levels in GC tissues. Interestingly, RUNX3 expression was negatively correlated with CDX2 expression in other tissues. CDX2 overexpression or Res treatment inhibited cell proliferation, migration, and invasion, while inducing cell apoptosis. Furthermore, RUNX3 and B-cell lymphoma-2 (Bcl-2)-associated X protein (Bax) expression levels were increased, while those of of β-catenin, TCF-4, and Bcl-2 were decreased in the CDX2 group. Upon treatment with lithium chloride (LiCl), the proliferation, migration, and invasion of CDX2-overexpressing MKN7 and TMK1 cells were enhanced. Our results indicate that Res inhibits the growth of MKN7 and TMK1 cells by increasing RUNX3 and CDX2 expression levels, with the potential involvement of the β-catenin/TCF-4 signaling pathway.

Background: Radioimmunotherapy with cetuximab and conjugates with various radioisotopes is a feasible treatment option for different tumor models. Scandium-47 (47Sc), one of several β−-particle-emitting radioisotopes, displays favorable physical and chemical properties for conjugation to monoclonal antibodies. However, the therapeutic efficacy of 47Sc in preclinical and clinical studies is largely unknown. Given that intrinsic alterations in tumors greatly contribute to resistance to anti-epidermal growth factor receptor (EGFR)-targeted therapy, research on overcoming resistance to radioimmunotherapy using cetuximab is required. Methods: 47Sc was produced by irradiation of a CaCO3 target at the HANARO research reactor in KAERI (Korea Atomic Energy Research Institute) and prepared by chromatographic separation of the irradiated target. Cetuximab was conjugated with 47Sc using the bifunctional chelating agent DTPA. Radiochemical purity was determined using instant thin-layer chromatography. The immunoreactivity of 47Sc-DTPA-cetuximab was evaluated using the Lindmo method and an in vitro cell-binding assay. The inhibitory effects of cetuximab and 47Sc-DTPA-cetuximab were confirmed using cell growth inhibition and BrdU cell proliferation assays. Differences in protein expression levels between cetuximab- and 47Sc-DTPA-cetuximab-treated cells were confirmed using western blotting. Complex formation between RUNX3 and DNA repair components was confirmed using immunoprecipitation and western blotting. Results: Cetuximab induces cell cycle arrest and cell death in EGFR-overexpressing NSCLC cells. Radiolabeling of cetuximab with 47Sc led to increased therapeutic efficacy relative to cetuximab alone. Application of 47Sc-DTPA-cetuximab induced DNA damage responses, and activation of RUNX3 significantly enhanced the therapeutic efficacy of 47Sc-DTPA-cetuximab. RUNX3 mediated susceptibility to EGFR-targeted NSCLC therapy using 47Sc-DTPA-cetuximab via interaction with components of the DNA damage and repair machinery. Conclusions: 47Sc-DTPA-cetuximab promoted cell death in EGFR-overexpressing NSCLC cells by targeting EGFR and inducing DNA damage as a result of β irradiation emitted from the conjugated 47Sc. Activation of RUNX3 played a key role in DNA damage and repair processes in response to the ionizing radiation and inhibited cell growth, thus leading to more effective tumor suppression. RUNX3 can potentially moderate susceptibility to 47Sc-conjugated cetuximab by modulating DNA damage and repair process mechanisms. [ABSTRACT FROM AUTHOR]

Schwann cells (SCs) play a crucial role in peripheral nerve injury and regeneration. Recently, RUNX3 was found to be linked with neurological dysfunction. We examined the RUNX3 expression in sciatic nerve stumps with peripheral nerve injury of rats, cyclic adenosine monophosphate (cAMP)-induced SCs. MTT assay was applied to determine the proliferation of SCs. Cell migration and apoptosis were assessed using wound healing assay and flow cytometry. Subsequently, we detected the methylation level of RUNX3 using Methylation-specific PCR assay and verified its regulation by DNMT1. The RUNX3 expressions were increased in sciatic nerve stumps with peripheral nerve injury and cAMP-induced SCs differentiation, which were related to demethylation of its promoter region regulated by DNMT1. RUNX3 knockdown notably suppressed the proliferation and migration, and induced the cell apoptosis of SCs. Silencing of RUNX3 inhibited the cAMP-induced morphological changes of SCs and the increase of myelin-related proteins induced by cAMP in SCs, while RUNX3 overexpression exerted opposite effects. Besides, the overexpression of RUNX3 promoted the activation of JAK/STAT signaling to regulate SCs proliferation and myelination. Meanwhile, DNMT1 overexpression inhibited the expression of RUNX3, and cell proliferation and myelination. In conclusion, RUNX3 mediated by DNMT1 regulated SC proliferation and myelination via JAK/STAT signaling pathway. [Display omitted] • RUNX3 was increased in injured sciatic nerves and cAMP-induced SCs. • Si- RUNX3 suppressed proliferation and migration, and induced apoptosis of SCs. • Si- RUNX3 inhibited the increases of myelin-related proteins induced by cAMP in SCs. • DNMT1 inhibited RUNX3 expression by the regulation of methylation. • DNMT1/RUNX3/JAK2/STAT3 axis regulated SC proliferation and myelination. [ABSTRACT FROM AUTHOR]

RUNX3 is a transcription factor and tumor suppressor that is silenced or inactivated in diverse tumors. The effect of RUNX3 on the epithelial–mesenchymal transition in clear-cell renal cell carcinoma (CCRCC) remains unclear. We determined the expression of RUNX3 and E-cadherin in tumor tissues and adjacent normal tissues of 30 CCRCC patients; established cultured CCRCC cells with the overexpression of RUNX3; and examined the in vivo tumorigenic function of RUNX3 in a nude mouse xenograft model of CCRCC. RUNX3 and E-cadherin were downregulated in human CCRCC samples. Cell lines with RUNX3 overexpression had reduced cell proliferation, invasion, and migration, a prolonged cell cycle, increased apoptosis, and increased expression of E-cadherin. In the nude mouse xenograft model of CCRCC, tumors with the overexpression of RUNX3 had smaller volumes and weights and had increased expression of E-cadherin. In conclusion, RUNX3 overexpression increased the level of E-cadherin and inhibited the proliferation, invasion, and migration of CCRCC in vitro and in vivo. RUNX3 has potential use as a biomarker for prognostic monitoring of CCRCC and as a therapeutic target for the treatment of this cancer.

The RUNX transcription factors are frequently dysregulated in human cancers, suggesting their potential as attractive targets for drug treatment. However, all three transcription factors have been described as both tumor suppressors and oncogenes, indicating the need to determine their molecular mechanisms of action. Although RUNX3 has long been considered a tumor suppressor in human cancers, several recent studies have shown that RUNX3 is upregulated during the development or progression of various malignant tumors, suggesting it may act as a "conditional" oncogene. Resolving this paradox and understanding how a single gene can exhibit both oncogenic and tumor-suppressive properties is essential for successful drug targeting of RUNX. This review describes the evidence for the activities of RUNX3 in human cancer and proposes an explanation for the duality of RUNX3 involving the status of p53. In this model, p53 deficiency causes RUNX3 to become oncogenic, leading to aberrant upregulation of MYC. [ABSTRACT FROM AUTHOR]

The RUNX family of transcription factors, including RUNX1, RUNX2, and RUNX3, are key regulators of development and can function as either tumor suppressors or oncogenes in cancer. Emerging evidence suggests that the dysregulation of RUNX genes can promote genomic instability in both leukemia and solid cancers by impairing DNA repair mechanisms. RUNX proteins control the cellular response to DNA damage by regulating the p53, Fanconi anemia, and oxidative stress repair pathways through transcriptional or non-transcriptional mechanisms. This review highlights the importance of RUNX-dependent DNA repair regulation in human cancers. [ABSTRACT FROM AUTHOR]

Background: Extranodal natural killer/T-cell lymphoma (NKTL) is an aggressive type of non-Hodgkin lymphoma with dismal outcome. A better understanding of disease biology and key oncogenic process is necessary for the development of targeted therapy. Super-enhancers (SEs) have been shown to drive pivotal oncogenes in various malignancies. However, the landscape of SEs and SE-associated oncogenes remain elusive in NKTL. Methods: We used Nano-ChIP-seq of the active enhancer marker histone H3 lysine 27 acetylation (H3K27ac) to profile unique SEs NKTL primary tumor samples. Integrative analysis of RNA-seq and survival data further pinned down high value, novel SE oncogenes. We utilized shRNA knockdown, CRISPR-dCas9, luciferase reporter assay, ChIP-PCR to investigate the regulation of transcription factor (TF) on SE oncogenes. Multi-color immunofluorescence (mIF) staining was performed on an independent cohort of clinical samples. Various function experiments were performed to evaluate the effects of TOX2 on the malignancy of NKTL in vitro and in vivo. Results: SE landscape was substantially different in NKTL samples in comparison with normal tonsils. Several SEs at key transcriptional factor (TF) genes, including TOX2, TBX21(T-bet), EOMES, RUNX2, and ID2, were identified. We confirmed that TOX2 was aberrantly overexpressed in NKTL relative to normal NK cells and high expression of TOX2 was associated with worse survival. Modulation of TOX2 expression by shRNA, CRISPR-dCas9 interference of SE function impacted on cell proliferation, survival and colony formation ability of NKTL cells. Mechanistically, we found that RUNX3 regulates TOX2 transcription by binding to the active elements of its SE. Silencing TOX2 also impaired tumor formation of NKTL cells in vivo. Metastasis-associated phosphatase PRL-3 has been identified and validated as a key downstream effector of TOX2-mediated oncogenesis. Conclusions: Our integrative SE profiling strategy revealed the landscape of SEs, novel targets and insights into molecular pathogenesis of NKTL. The RUNX3-TOX2-SE-TOX2-PRL-3 regulatory pathway may represent a hallmark of NKTL biology. Targeting TOX2 could be a valuable therapeutic intervene for NKTL patients and warrants further study in clinic. [ABSTRACT FROM AUTHOR]

Simple Summary: We studied the expression of several protein biomarkers in both stromal and tumor tissue from colon cancer patients. High expression of IRS1 in stromal tissue and RUNX3 and SMAD4 in both stromal and tumor tissue were positive prognostic factors. Of particular interest, RUNX3 expression in stromal tissue was associated with the density of tumor-infiltrating lymphocytes. This finding may be important for understanding the prognostic impact of lymphocytes and predicting and increasing the efficacy of immunotherapy in colon cancer. Colon cancer is a common malignancy and a major contributor to human morbidity and mortality. In this study, we explore the expression and prognostic impact of IRS-1, IRS-2, RUNx3, and SMAD4 in colon cancer. Furthermore, we elucidate their correlations with miRs 126, 17-5p, and 20a-5p, which are identified as potential regulators of these proteins. Tumor tissue from 452 patients operated for stage I–III colon cancer was retrospectively collected and assembled into tissue microarrays. Biomarkers' expressions were examined by immunohistochemistry and analyzed using digital pathology. In univariate analyses, high expression levels of IRS1 in stromal cytoplasm, RUNX3 in tumor (nucleus and cytoplasm) and stroma (nucleus and cytoplasm), and SMAD4 in tumor (nucleus and cytoplasm) and stromal cytoplasm were related to increased disease-specific survival (DSS). In multivariate analyses, high expression of IRS1 in stromal cytoplasm, RUNX3 in tumor nucleus and stromal cytoplasm, and high expression of SMAD4 in tumor and stromal cytoplasm remained independent predictors of improved DSS. Surprisingly, with the exception of weak correlations (0.2 < r < 0.25) between miR-126 and SMAD4, the investigated markers were mostly uncorrelated with the miRs. However, weak to moderate/strong correlations (0.3 < r < 0.6) were observed between CD3 and CD8 positive lymphocyte density and stromal RUNX3 expression. High expression levels of IRS1, RUNX3, and SMAD4 are positive prognostic factors in stage I–III colon cancer. Furthermore, stromal expression of RUNX3 is associated with increased lymphocyte density, suggesting that RUNX3 is an important mediator during recruitment and activation of immune cells in colon cancer. [ABSTRACT FROM AUTHOR]

RUNX3 is a transcription factor with regulatory roles in cell proliferation and development. While largely characterized as a tumor suppressor, RUNX3 can also be oncogenic in certain cancers. Many factors account for the tumor suppressor function of RUNX3, which is reflected by its ability to suppress cancer cell proliferation after expression-restoration, and its inactivation in cancer cells. Ubiquitination and proteasomal degradation represent a major mechanism for the inactivation of RUNX3 and the suppression of cancer cell proliferation. On the one hand, RUNX3 has been shown to facilitate the ubiquitination and proteasomal degradation of oncogenic proteins. On the other hand, RUNX3 can be inactivated through the ubiquitin–proteasome system. This review encapsulates two facets of RUNX3 in cancer: how RUNX3 suppresses cell proliferation by facilitating the ubiquitination and proteasomal degradation of oncogenic proteins, and how RUNX3 is degraded itself through interacting RNA-, protein-, and pathogen-mediated ubiquitination and proteasomal degradation. [ABSTRACT FROM AUTHOR]

A cell cycle is a series of events that takes place in a cell as it grows and divides. At the G1 phase of cell cycle, cells monitor their cumulative exposure to specific signals and make the critical decision to pass through the restriction (R)-point. The R-point decision-making machinery is fundamental to normal differentiation, apoptosis, and G1–S transition. Deregulation of this machinery is markedly associated with tumorigenesis. Therefore, identification of the molecular mechanisms that govern the R-point decision is one of the fundamental issues in tumor biology. RUNX3 is one of the genes frequently inactivated in tumors by epigenetic alterations. In particular, RUNX3 is downregulated in most K-RAS-activated human and mouse lung adenocarcinomas (ADCs). Targeted inactivation of Runx3 in the mouse lung induces adenomas (ADs), and markedly shortens the latency of ADC formation induced by oncogenic K-Ras. RUNX3 participates in the transient formation of R-point-associated activator (RPA-RX3-AC) complexes, which measure the duration of RAS signals and thereby protect cells against oncogenic RAS. This review focuses on the molecular mechanism by which the R-point participates in oncogenic surveillance. [ABSTRACT FROM AUTHOR]

CAR-T therapy has shown successful in the treatment of certain types of hematological malignancy, while the efficacy of CAR-T cell in treating solid tumors has been limited due to the exhaustion of CAR-T caused by the tumor microenvironment in solid tumors. Therefore, improving the exhaustion of CAR-T cell is one of the inspiring strategies for CAR-T treatment of solid tumors. As an important regulator in T cell immunity, the transcription factor RUNX3 not only negatively regulates the terminal differentiation T-bet gene, reducing the ultimate differentiation of T cells, but also increases the residency of T cells in non-lymphoid tissues and tumors. By overexpressing RUNX3 in CAR-T cells, we found that increasing the expression of RUNX3 maintained the low differentiation of CAR-T cells, further improving the exhaustion of CAR-T cells during antigen stimulation. In vitro, we found that RUNX3 could reduce the release of cytokines while maintaining CAR-T cells function. In re-challenge experiments, CAR-T cells overexpressing RUNX3 (Runx3-OE CAR-T) were safer than conventional CAR-T cells, while RUNX3 could also maintain the anti-tumor efficacy of CAR-T cells in vivo. Collectively, we found that Runx3-OE CAR-T cells can improve CAR-T phenotype and reduce cytokines release while maintaining CAR-T cells function, which may improve the safety of CAR-T therapy in clinical trials. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) has a number of adverse effects on the reproductive development of females. In particular, the mechanism of disruption of ovarian development in adolescent mice is still unclear. Based on transcriptome sequencing results, a differentially expressed lncRNA, Fhad1os2, was detected in the ovaries of BPA-exposed pubertal mice. In our study, the lncRNA Fhad1os2, localized in the ovarian granulosa cell cytoplasm, could regulate the proliferation of mouse ovarian granulosa cells. Mechanistically, the results of RNA pull-down experiments as well as mass spectrometry analysis showed that ERα, an interfering signaling molecule of BPA, could directly bind lncRNA Fhad1os2 and decrease the transcription of lncRNA Fhad1os2 in response to the estrogen-like effect of BPA. BPA exposure also caused abnormal lncRNA Fhad1os2 pulldown protein-related signaling pathways in the ovaries of adolescent mice. Furthermore, lncRNA Fhad1os2 interacted with RUNX3, a transcription factor related to follicle development and hormone synthesis. As a negative regulator, lncRNA Fhad1os2 transactivated the expression of Runx3, which in turn induced RUNX3 to positively regulate aromatase (Cyp19a1) expression in mouse ovarian granulosa cells and promote estrogen synthesis. In conclusion, our study indicates that BPA exposure interferes with ERα-regulated lncRNA Fhad1os2 interactions with RUNX3 in pubertal mice, affecting estrogen synthesis in mouse granulosa cells and contributing to premature ovarian maturation in pubertal mice.

BACKGROUND: Non-small cell lung cancer (NSCLC) is the most commonly diagnosed solid tumor. Natural killer (NK) cell-based immunotherapy is a promising anti-tumor strategy in various cancers including NSCLC. OBJECTIVE: We aimed to investigate the specific mechanisms that regulate the killing effect of NK cells to NSCLC cells. METHODS: Reverse transcription-quantitative PCR (RT-qPCR) assay was applied to measure the levels of hsa-microRNA (miR)-301a-3p and Runt-related transcription factor 3 (RUNX3). Enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of IFN- γ and TNF- α. Lactate dehydrogenase assay was applied to detect the killing effect of NK cells. Dualluciferase reporter assay and RNA immunoprecipitation (RIP) assay were carried out to confirm the regulatory relationship between hsa-miR-301a-3p and RUNX3. RESULTS: A low expression of hsa-miR-301a-3p was observed in NK cells stimulated by IL-2. The levels of IFN- γ and TNF- α were increased in NK cells of the IL-2 group. Overexpression of hsa-miR-301a-3p reduced the levels of IFN- γ and TNF- α as well as the killing effect of NK cells. Furthermore, RUNX3 was identified to be a target of hsamiR-301a-3p. hsa-miR-301a-3p suppressed the cytotoxicity of NK cells to NSCLC cells by inhibiting the expression of RUNX3. We found hsa-miR-301a-3p promoted tumor growth by suppressing the killing effect of NK cells against NSCLC cells in vivo. CONCLUSIONS: Hsa-miR-301a-3p suppressed the killing effect of NK cells on NSCLC cells by targeting RUNX3, which may provide promising strategies for NK cell-based antitumor therapies. [ABSTRACT FROM AUTHOR]

Dissecting and identifying the major actors and pathways in the genesis, progression and aggressive advancement of breast cancer is challenging, in part because neoplasms arising in this tissue represent distinct diseases and in part because the tumors themselves evolve. This review attempts to illustrate the complexity of this mutational landscape as it pertains to the RUNX genes and their transcription co-factor CBFβ. Large-scale genomic studies that characterize genetic alterations across a disease subtype are a useful starting point and as such have identified recurring alterations in CBFB and in the RUNX genes (particularly RUNX1). Intriguingly, the functional output of these mutations is often context dependent with regards to the estrogen receptor (ER) status of the breast cancer. Therefore, such studies need to be integrated with an in-depth understanding of both the normal and corrupted function in mammary cells to begin to tease out how loss or gain of function can alter the cell phenotype and contribute to disease progression. We review how alterations to RUNX/CBFβ function contextually ascribe to breast cancer subtypes and discuss how the in vitro analyses and mouse model systems have contributed to our current understanding of these proteins in the pathogenesis of this complex set of diseases. [ABSTRACT FROM AUTHOR]

The runt-related transcription factors (RUNX) play prominent roles in cell cycle progression, differentiation, apoptosis, immunity and epithelial–mesenchymal transition. There are three members in the mammalian RUNX family, each with distinct tissue expression profiles. RUNX genes play unique and redundant roles during development and adult tissue homeostasis. The ability of RUNX proteins to influence signaling pathways, such as Wnt, TGFβ and Hippo-YAP, suggests that they integrate signals from the environment to dictate cell fate decisions. All RUNX genes hold master regulator roles, albeit in different tissues, and all have been implicated in cancer. Paradoxically, RUNX genes exert tumor suppressive and oncogenic functions, depending on tumor type and stage. Unlike RUNX1 and 2, the role of RUNX3 in stem cells is poorly understood. A recent study using cancer-derived RUNX3 mutation R122C revealed a gatekeeper role for RUNX3 in gastric epithelial stem cell homeostasis. The corpora of RUNX3R122C/R122C mice showed a dramatic increase in proliferating stem cells as well as inhibition of differentiation. Tellingly, RUNX3R122C/R122C mice also exhibited a precancerous phenotype. This review focuses on the impact of RUNX3 dysregulation on (1) stem cell fate and (2) the molecular mechanisms underpinning early carcinogenesis. [ABSTRACT FROM AUTHOR]

Introduction: The aim of the study was to determine the role and mechanism of runt-related transcription factor 3 (Runx3) in the development of asthma. Methods: An asthma mouse model was constructed and validated by hematoxylin-eosin analysis of lung tissue and noninvasive enhanced pause (Penh) evaluation of airway hyperresponsiveness. Then, the levels of Runx3 and interleukin (IL)-12 in peripheral blood and lung tissue were detected by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry. By use Runx3+/− mice, the effect of Runx3 downregulation on ovalbumin (OVA)-induced asthma was investigated. After stimulated by different doses of IL-12, the expressions of Runx3, hypoxia inducible factor-1α (HIF-1α), and NOD-like receptor thermal protein domain associated protein 3 (NLRP3) in BEAS-2B cells were tested through Western blot and immunofluorescence. Subsequently, BEAS-2B cells treated with 20 ng/mL IL-12 were divided into control, Runx3 overexpression negative control, Runx3 overexpression, HIF-1α inhibitor, and Runx3 overexpression + HIF-1α agonist groups. The Western blot, immunofluorescence, and ELISA indicators were tested repeatedly. Results: The increased number of inflammatory cells and Penh value confirmed the success of the asthma mouse model. IL-12 expression was significantly increased, and Runx3 was reduced in asthma mice compared with wild-type mice. Meanwhile, the level of immunoglobulin E (IgE) in serum, cytokines in bronchoalveolar lavage fluid, and IL-12, HIF-1α, NLRP3 in the lung were significantly elevated in Runx3+/− mice. With the increase of IL-12 concentration, Runx3 protein expression decreased, while HIF-1α and NLRP3 expression increased. Further mechanistic studies suggest that Runx3 ameliorates IL-12-induced BEAS-2B injury by inhibiting HIF-1α/NLRP3 pathway. Conclusion: These results suggested that IL-12 contributes to the development of asthma by targeting HIF-1α/NLRP3 pathway through Runx3, thus providing a novel strategy for asthma therapy. [ABSTRACT FROM AUTHOR]

Abstract Background Hepatocellular carcinoma (HCC) is the most common primary hepatic malignancy of adults. RUNX3 and p16 are tumor suppressor genes that may be inactivated by hypermethylation which is a key epigenetic mechanism that contributes to the initiation and progression of various types of human carcinomas including HCC. The aim of this study was to assess the association of hypermethylation of RUNX3 and p16 gene promoters with the incidence of HCC in Egyptian patients. The study included 120 subjects: 30 HCC patients, 30 patients with hepatitis C virus (HCV) without cirrhosis, 30 cirrhotic patients, and 30 healthy volunteers. Methylation-specific polymerase chain reaction (PCR) was done for detection of hypermethylated p16 and RUNX3. Serum levels of liver enzymes and albumin were detected spectrophotometrically and alpha fetoprotein (AFP) was measured in serum by ELISA. Results Methylation of RUNX3 and p16 was detected in 25/30 (83.3%) and 26/30 (86.7%) of HCC patients, respectively. The methylation state of both RUNX3 and p16 genes was significantly higher in HCC patients compared to the control subjects (P = 0.016, OR = 4.38) and (P = 0.014, OR = 4.97), respectively. The methylation of both promoters was associated with higher AFP levels in the serum of all patients. Conclusions Hypermethylation of RUNX3 and p16 is significantly associated with the development of HCC and may be implicated in its pathogenesis.

Abstract Background Targeting glutamine metabolism is previously indicated as a potential and attractive strategy for gastric cancer (GC) therapy. However, the underlying mechanisms responsible for the modification of glutamine metabolism in GC cells have not been fully elucidated. Accordingly, the current study sought to investigate the physiological mechanisms of RUNX3-mediated circDYRK1A in glutamine metabolism of GC. Methods Firstly, GC tissues and adjacent normal tissues were obtained from 50 GC patients to determine circDYRK1A expression in GC tissues. Next, the binding affinity among RUNX3, circDYRK1A, miR-889-3p, and FBXO4 was detected to clarify the mechanistic basis. Moreover, GC cells were subjected to ectopic expression and knockdown manipulations of circDYRK1A, miR-889-3p, and/or FBXO4 to assay GC cell malignant phenotypes, levels of glutamine, glutamic acid, and α-KG in cell supernatant and glutamine metabolism-related proteins (GLS and GDH). Finally, nude mice were xenografted with GC cells to explore the in vivo effects of circDYRK1A on the tumorigenicity and apoptosis. Results circDYRK1A was found to be poorly expressed in GC tissues. RUNX3 was validated to bind to the circDYRK1A promoter, and circDYRK1A functioned as a miR-889-3p sponge to up-regulate FBXO4 expression. Moreover, RUNX3-upregulated circDYRK1A reduced levels of glutamine, glutamic acid, and α-KG, and protein levels of GLS and GDH, and further diminished malignant phenotypes in vitro. Furthermore, in vivo experimentation substantiated that circDYRK1A inhibited the tumorigenicity and augmented the apoptosis in GC. Conclusion In conclusion, these findings highlighted the significance and mechanism of RUNX3-mediated circDYRK1A in suppressing glutamine metabolism in GC via the miR-889-3p/FBXO4 axis.