Targeting the RUNX3-miR-186-3p-DAT-IGF1R axis as a therapeutic strategy in a Parkinson's disease model.

With the increasing age of the population worldwide, the incidence rate of Parkinson's disease (PD) is increasing annually. Currently, the treatment strategy for PD only improves clinical symptoms. No effective treatment strategy can slow down the progression of the disease. In the present study, whole transcriptome sequencing was used to obtain the mRNA and miRNA expression profiles in a PD mouse model, which revealed the pathogenesis of PD. The transcription factor RUNX3 upregulated the miR-186-3p expression in the PD model. Furthermore, the high miR-186-3p expression in PD can be targeted to inhibit the DAT expression, resulting in a decrease in the dopamine content of dopaminergic neurons. Moreover, miR-186-3p can be targeted to inhibit the IGF1R expression and prevent the activation of the IGF1R-P-PI3K-P-AKT pathway, thus increasing the apoptosis of dopaminergic neurons by regulating the cytochrome c-Bax-cleaved caspase-3 pathway. Our research showed that the RUNX3-miR-186-3p-DAT-IGF1R axis plays a key role in the pathogenesis of PD, and miR-186-3p is a potential target for the treatment of PD.

Striking a balance: the Goldilocks effect of CD8α expression on NK cells.

NK cells are cytotoxic innate immune cells involved in antitumor immunity, and they provide a treatment option for patients with acute myeloid leukemia (AML). In this issue of the JCI, Cubitt et al. investigated the role of CD8α, a coreceptor present on approximately 40% of human NK cells. IL-15 stimulation of CD8α- NK cells induced CD8α expression via the RUNX3 transcription factor, driving formation of a unique induced CD8α (iCD8α+) population. iCD8α+ NK cells displayed higher proliferation, metabolic activity, and antitumor cytotoxic function compared with preexisting CD8α+ and CD8α- subsets. Therefore, CD8α expression can be used to define a potential dynamic spectrum of NK cell expansion and function. Because these cells exhibit enhanced tumor control, they may be used to improve in NK cell therapies for patients with AML.

Differential methylation of DNA promoter sequences in peripheral blood mononuclear cells as promising diagnostic biomarkers for colorectal cancer.

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.

A pan-cancer single-cell transcriptional analysis of antigen-presenting cancer-associated fibroblasts in the tumor microenvironment.

Background: Cancer-associated fibroblasts (CAFs) are the primary stromal cells found in tumor microenvironment, and display high plasticity and heterogeneity. By using single-cell RNA-seq technology, researchers have identified various subpopulations of CAFs, particularly highlighting a recently identified subpopulation termed antigen-presenting CAFs (apCAFs), which are largely unknown. Methods: We collected datasets from public databases for 9 different solid tumor types to analyze the role of apCAFs in the tumor microenvironment. Results: Our data revealed that apCAFs, likely originating mainly from normal fibroblast, are commonly found in different solid tumor types and generally are associated with anti-tumor effects. apCAFs may be associated with the activation of CD4+ effector T cells and potentially promote the survival of CD4+ effector T cells through the expression of C1Q molecules. Moreover, apCAFs exhibited highly enrichment of transcription factors RUNX3 and IKZF1, along with increased glycolytic metabolism. Conclusions: Taken together, these findings offer novel insights into a deeper understanding of apCAFs and the potential therapeutic implications for apCAFs targeted immunotherapy in cancer.

RUNX3 exerts tumor-suppressive role through inhibiting EXOSC4 expression.

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.

Combination of androgen and estrogen improves asthma by mediating Runx3 expression.

Objective: Asthma is a chronic heterogeneous airway disease, and imbalanced T-helper type 1 (Th1) and Th2 cell-mediated inflammation contribute to its pathogenesis. Although it has been suggested that androgen and estrogen were involved in development of asthma, the underlying mechanisms remained largely unclear. Studies have demonstrated that Runx3 could promote naive CD4+ T cells to differentiate into Th1 cells. Hence, our study aimed to explore the potential regulatory mechanism of androgen and estrogen on asthma via modulating Runx3. Methods: First, clinical assessments and pulmonary function tests were conducted on 35 asthma patients and 24 healthy controls. The concentrations of androgen, estrogen, and androgen estrogen ratios were assessed in peripheral blood samples of asthma patients and healthy controls. Then, a murine asthma model was established to explore the effects of estrogen and androgen (alone or in combination) on asthma. Third, an in vitro assay was used to explore the mechanism of combination of androgen and estrogen in asthma. Results: We observed decreased androgen and increased estrogen levels in asthma patients compared with healthy controls. In mice with experimental asthma, there were increased serum concentrations of estrogen and decreased serum concentrations of androgen, intervention with combination of androgen and estrogen alleviated airway inflammations, increased Runx3 expressions and elevated Th1 differentiation. In CD4+ T cells co-cultured with bronchial epithelial cells (BECs), treatment with androgen plus estrogen combination promoted Th1 differentiation, which was mitigated by Runx3 knockdown in BECs and enhanced by Runx3 overexpression. Conclusion: These findings suggest that androgen estrogen combination modulate the Th1/Th2 balance via regulating the expression of Runx3 in BECs, thereby providing experimental evidence supporting androgen and estrogen combination as a novel therapy for asthma.

Expression pattern of Runt-related transcription factor (RUNX) family members and the role of RUNX1 during kidney development.

Runt-related transcription factor (RUNX) family members play critical roles in the development of multiple organs. Mammalian RUNX family members, consisting of RUNX1, RUNX2, and RUNX3, have distinct tissue-specific expression and function. In this study, we examined the spatiotemporal expression patterns of RUNX family members in developing kidneys and analyzed the role of RUNX1 during kidney development. In the developing mouse kidney, RUNX1 protein was strongly expressed in the ureteric bud (UB) tip and weakly expressed in the distal segment of the renal vesicle (RV), comma-shaped body (CSB), and S-shaped body (SSB). In contrast, RUNX2 protein was restricted to the stroma, and RUNX3 protein was only expressed in immune cells. We also analyzed the expression of RUNX family members in the cynomolgus monkey kidney. We found that expression patterns of RUNX2 and RUNX3 were conserved between rodents and primates, whereas RUNX1 was only expressed in the UB tip, not in the RV, CSB, or SSB of cynomolgus monkeys, suggesting a species differences. We further evaluated the roles of RUNX1 using two different conditional knockout mice: Runx1f/f:HoxB7-Cre and Runx1f/f:R26-CreERT2 and found no abnormalities in the kidney. Our findings showed that RUNX1, which is mainly expressed in the UB tip, is not essential for kidney development.

Downregulation of lncRNA MIR17HG reduced tumorigenicity and Treg-mediated immune escape of non-small-cell lung cancer cells through targeting the miR-17-5p/RUNX3 axis.

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-ß), 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-ß, 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.

RUNX3 alleviates mitochondrial dysfunction and tubular damage by inhibiting TLR4/NF-κB signalling pathway in diabetic kidney disease.

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.

N-ethyl-N-nitrosourea (ENU)-induced C-terminal truncation of Runx3 results in autoimmune colitis associated with Th17/Treg imbalance.

Inflammatory bowel disease (IBD) is a chronic and progressive inflammatory intestinal disease that affects people around the world. The primary cause of IBD is an imbalance in the host immune response to intestinal flora. Several human genes, including IL10, STAT3, IRGM, ATG16L1, NOD2 and RUNX3, are associated with inappropriate immune responses in IBD. It has been reported that homozygous Runx3-knockout (ko) mice spontaneously develop colitis. However, the high mortality rate in these mice within the first two weeks makes it challenging to study the role of Runx3 in colitis. To address this issue, a spontaneous colitis (SC) mouse model carrying a C-terminal truncated form of Runx3 with Tyr319stop point mutation has been generated. After weaning, SC mice developed spontaneous diarrhea and exhibited prominent enlargement of the colon, accompanied by severe inflammatory cell infiltration. Results of immunofluorescence staining showed massive CD4+ T cell infiltration in the inflammatory colon of SC mice. Colonic IL-17A mRNA expression and serum IL-17A level were increased in SC mice. CD4+ T cells from SC mice produced stronger IL-17A than those from wildtype mice in Th17-skewing conditions in vitro. In addition, the percentages of Foxp3+ Treg cells as well as the RORγt+Foxp3+ Treg subset, known for its role in suppressing Th17 response in the gut, were notably lower in colon lamina propria of SC mice than those in WT mice. Furthermore, transfer of total CD4+ T cells from SC mice, but not from wildtype mice, into Rag1-ko host mice resulted in severe autoimmune colitis. In conclusion, the C-terminal truncated Runx3 caused autoimmune colitis associated with Th17/Treg imbalance. The SC mouse model is a feasible approach to investigate the effect of immune response on spontaneous colitis.

USP7 promotes IgA class switching through stabilizing RUNX3 for germline transcription activation.

Class switch recombination (CSR) diversifies the effector functions of antibodies and involves complex regulation of transcription and DNA damage repair. Here, we show that the deubiquitinase USP7 promotes CSR to immunoglobulin A (IgA) and suppresses unscheduled IgG switching in mature B cells independent of its role in DNA damage repair, but through modulating switch region germline transcription. USP7 depletion impairs Sα transcription, leading to abnormal activation of Sγ germline transcription and increased interaction with the CSR center via loop extrusion for unscheduled IgG switching. Rescue of Sα transcription by transforming growth factor ß (TGF-ß) in USP7-deleted cells suppresses Sγ germline transcription and prevents loop extrusion toward IgG CSR. Mechanistically, USP7 protects transcription factor RUNX3 from ubiquitination-mediated degradation to promote Sα germline transcription. Our study provides evidence for active transcription serving as an anchor to impede loop extrusion and reveals a functional interplay between USP7 and TGF-ß signaling in promoting RUNX3 expression for efficient IgA CSR.

Runx3 Regulates CD8+ T Cell Local Expansion and CD43 Glycosylation in Mice by H1N1 Influenza A Virus Infection.

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.

The CD4 Versus CD8 T Cell Fate Decision: A Multiomics-Informed Perspective.

The choice of developing thymocytes to become CD8+ cytotoxic or CD4+ helper T cells has been intensely studied, but many of the underlying mechanisms remain to be elucidated. Recent multiomics approaches have provided much higher resolution analysis of gene expression in developing thymocytes than was previously achievable, thereby offering a fresh perspective on this question. Focusing on our recent studies using CITE-seq (cellular indexing of transcriptomes and epitopes) analyses of mouse thymocytes, we present a detailed timeline of RNA and protein expression changes during CD8 versus CD4 T cell differentiation. We also revisit our current understanding of the links between T cell receptor signaling and expression of the lineage-defining transcription factors ThPOK and RUNX3. Finally, we propose a sequential selection model to explain the tight linkage between MHC-I versus MHC-II recognition and T cell lineage choice. This model incorporates key aspects of previously proposed kinetic signaling, instructive, and stochastic/selection models.

RUNX3 regulates trastuzumab resistance of gastric cancer cells: a metabolomic analysis based on UPLC-Q Exactive Focus Orbitrap mass spectrometry / 南方医科大学学报

OBJECTIVE@#To explore the role of Runt-related transcription factor 3 (RUNX3) in metabolic regulation of trastuzumab-resistant gastric cancer cells and investigate the mechanism of RUNX3 knockdown-mediated reversal of trastuzumab resistance.@*METHODS@#We performed a metabolomic analysis of trastuzumab-resistant gastric cancer cells (NCI N87R) and RUNX3 knockdown cells (NCI N87R/RUNX3) using ultra performance liquid chromatography (UPLC) coupled with Q Exactive Focus Orbitrap mass spectrometry (MS). Multivariate combined with univariate analyses and MS/MS ion spectrums were used to screen the differential variables. MetaboAnalyst 5.0 database was employed for pathway enrichment analysis. Differential metabolites-genes regulatory relationships were constructed based on OmicsNet database. The changes in GSH/GSSG and NADPH/NADP ratios in NCI N87R/RUNX3 cells were measured using detection kits.@*RESULTS@#The metabolic profile of NCI N87R cells was significantly altered after RUNX3 knockdown, with 81 differential metabolites identified to contribute significantly to the classification, among which 43 metabolites were increased and 38 were decreased (P < 0.01). In NCI N87R cells, RUNX3 knockdown resulted in noticeable alterations in 8 pathways involving glutamine metabolism, glycolysis, glycerophospholipid, nicotinate-nicotinamide and glutathione metabolism, causing also significant reduction of intracellular GSH/GSSG and NADPH/NADP ratios (P < 0.01). The differential metabolites-genes network revealed a regulatory relationship between the metabolic molecules and genes.@*CONCLUSION@#RUNX3 reverses trastuzumab resistance in gastric cancer cells by regulating energy metabolism and oxidation-reduction homeostasis and may serve as a potential therapeutic target for trastuzumab-resistant gastric cancer.

Relationship between Expression of Runt-related Transcription Factor 3 and Enhancer of zeste Homolog 2 Proteins and Sensitivity to Neoadjuvant Chemotherapy in Locally Advanced Rectal Cancer / 中国医学科学院学报

Objective To investigate the expression and correlation of Runt-related transcription factor 3(RUNX3)and enhancer of zeste homolog 2(EZH2)in rectal cancer,and to reveal the relationship between the expression of RUNX3 and EZH2 and the sensitivity of XELOX regimen to neoadjuvant chemotherapy in locally advanced rectal cancer patients. Methods The carcinoma and paracancerous tissues of 31 patients with rectal adenocarcinoma and no preoperative antitumor therapy were selected as cancer group and paracancer group,respectively.The relative mRNA levels of RUNX3 and EZH2 in the two groups were measured by real-time quantitative reverse transcription-polymerase chain reaction,and the protein levels were determined by immunohistochemical assay.The expression of RUNX3 and EZH2 was compared between cancer tissue and paracancerous tissue.The pre-treatment wax blocks of 26 patients with locally advanced rectal cancer who received 3 cycles of XELOX regimen as neoadjuvant chemotherapy before surgery were selected as the pre-neoadjuvant therapy group,and the postoperative pathological wax blocks were selected as the post-neoadjuvant treatment group.Tumor regression grade(TRG)was determined to evaluate the efficacy of neoadjuvant therapy.Immunohistochemical assay was used to detect the protein levels of RUNX3 and EZH2 in the two groups,and then the relationship between the expression patterns of the two proteins and the efficacy of neoadjuvant chemotherapy was analyzed. Results Compared with paracancerous tissue,the cancer tissue showed down-regulated mRNA level and reduced positive protein expression rate of RUNX3,while up-regulated mRNA level(

Regulatory effects of miR-138 and RUNX3 on Th1/Th2 balance in peripheral blood of children with cough variant asthma / 中国当代儿科杂志

OBJECTIVES@#To study the expression levels of microRNA-138 (miR-138) and Runt-related transcription factor 3 (RUNX3) in peripheral blood of children with cough variant asthma (CVA) and their regulatory effects on Th1/Th2 balance.@*METHODS@#Sixty-five children with CVA (CVA group) and 30 healthy children (control group) were enrolled. Peripheral venous blood samples were collected for both groups, and CD4@*RESULTS@#Compared with the control group, the CVA group showed significantly decreased levels of IFN-γ and IL-2 from CD4@*CONCLUSIONS@#MiR-138 regulates Th1/Th2 balance by targeting RUNX3 in children with CVA, providing a new direction for the treatment of CVA.

RUNX3 Methylation, Loss of RUNX3 Expression and Clinicopathologic Findings according to Helicobacter pylori CagA in Gastric Carcinoma / 대한소화기학회지

BACKGROUND/AIMS: Helicobacter pylori cytotoxin-associated gene A (CagA) has been suggested to be involved in the inactivation of Runt-related transcription factor 3 (RUNX3), a known gastric carcinoma tumor suppressor gene. It remains unclear how H. pylori CagA initiates or maintains RUNX3 promoter methylation and inactivates its protein expression in gastric carcinoma. METHODS: RUNX3 promoter methylation status, RUNX3 expression, and H. pylori CagA were investigated in 76 sample pairs of gastric carcinoma tissue. The patients' medical records were reviewed. The association between RUNX3 methylation or loss of RUNX3 expression and clinicopathologic variables according to H. pylori CagA status were investigated. RESULTS: In gastric carcinoma patients with H. pylori CagA-positive infection, RUNX3 methylation did not show association with lymphatic invasion, venous invasion, and TNM stages. However RUNX3 methylation was observed more frequently in poorly differentiated adenocarcinoma and signet ring cell carcinoma (77.8% vs. 20.0%, p=0.023) in early stage. In gastric carcinoma patients with H. pylori CagA-positive infection, loss of RUNX3 expression did not show association with lymphatic invasion, venous invasion, and TNM stages. However loss of RUNX3 expression was observed more frequently in early gastric carcinoma than in advanced gastric carcinoma (84.2% vs. 75.0%, p=0.51), but this difference was not significant. CONCLUSIONS: In gastric carcinoma patients with H. pylori CagA-positive infection, RUNX3 methylation or loss of RUNX3 expression did not show correlation with lymphovascular invasion and TNM stages. In early gastric carcinoma patients with H. pylori CagA-positive infection, RUNX3 methylation was observed more in poorly differentiated adenocarcinoma and signet ring cell carcinoma.

DNA Methylation of RUNX3 in Papillary Thyroid Cancer

BACKGROUND/AIMS: The relationship between Runt-related transcription factor 3 (RUNX3) gene inactivation and various solid tumors has been reported; however, little information is available about RUNX3 in thyroid cancers. METHODS: We evaluated the DNA methylation of RUNX3 in 13 papillary thyroid cancer tissues and four thyroid cancer cell lines. Additionally, using reverse transcriptase-polymerase chain reaction, we analyzed RUNX3 gene expression in several thyroid cancer cell lines after treating with the demethylating agent 5-aza-2'-deoxycytidine (DAC). RESULTS: RUNX3 was hypermethylated in many thyroid cancer cell lines and in 10 of the 12 papillary thyroid cancer tissues. Treatment with DAC increased the expression of RUNX3 in some thyroid cancer cell lines. CONCLUSIONS: We suggest that RUNX3 is associated with thyroid carcinogenesis, and RUNX3 methylation is a potentially useful diagnostic marker for papillary thyroid cancer.

Epigenetic Regulation of RUNX3 in Thyroid Carcinoma

No abstract available.

Study of Methylation Pattern of de Novo DNA Methyltransferase Genes and its Correlation with DNA Methylation Pattern of RUNX3 in Individuals with Gastric Cancer from Northern Region of Brazil / Estudio del Estado de Metilación de Novo de Genes Metiltransferasas y su Correlación con el Patrón de Metilación de RUNX3 en Individuos con Cáncer Gástrico de la Región Norte del Brasil

Gastric cancer is the forth malignancy in frequency in the world. In the northern Brazil is the second neoplasia most frequent in males and the third most frequent in females. Genetic and epigenetic alterations are evolved on gastric carcinogenesis and DNA methylation is the epigenetic alteration better studied. We analyzed de novo DNA methyltransferases methylation pattern and its association with RUNX3 gene methylation pattern in Brazilian samples of intestinal-type and diffuse-type of gastric cancer. PCR methylation specific was used to evaluate DNA methylation pattern. Sixty-six samples were studied in this work. Only the gene RUNX3 presented altered methylation pattern, being methylated in 38.5% of gastric cancer intestinal-type samples and in 70% of gastric cancer diffuse-type samples and, by this reason, it should be evolved in the genesis of this neoplasia. There was a statistically significant difference among diffuse-type and intestinal-type samples (p=0.0418) and among normal and tumour tissues (p<0.0001) for RUNX3 gene but not to DNMT3A, DNMT3B e DNMT3 genes on CpG islands analyzed. Alteration of RUNX3 methylation pattern is not associated to de novo alteration of DNA methyltransferases methylation pattern on studied regionsTherefore, it becomes necessary a better comprehension of this phenomenon on gastric carcinogenesis.

El cáncer gástrico es la cuarta patología más frecuente en el mundo. En el norte del Brasil, es la segunda neoplasia más frecuente en hombres y la tercera en mujeres. Alteraciones genéticas y epigenéticas relacionadas con la carcinogénesis gástrica y la metilación del DNA son las alteraciones epigenéticas mejor estudiadas. En este trabajo, analizamos el estado de novo de metilación de genes DNA metiltransferases y su asociación con el estado de metilación del gen RUNX3 en muestras de individuos brasileños con cáncer gástrico de los tipos intestinal y difuso. Fue usada la Reacción en Cadena de la Polimerasa (PCR), metilación específica, para analizar el estado de metilación del DNA. Fueron estudiados 66 tejidos tumorales. Solamente el gen RUNX3 presentó un estado de metilación alterado, estuvo metilado en 38,5% de las muestras de cáncer gástrico tipo intestinal y en 70% de muestras de cáncer gástrico tipo difuso, lo que sugiere que estaría relacionado con la génesis de esta neoplasia. Hubo una diferencia estadística significativa entre muestras de los tipos difuso e intestinal (p=0.0418) y entre tejidos normal y tumoral (p<0.0001)parael gen RUNX3. Esta asociación no fue encontrada para los genes DNMT3A, DNMT3B y DNMT3 en las islas CpG analizadas. Alteraciones del estado de metilación de RUNX3 no están asociadas con alteraciones de novo de genes DNA metiltransferases. De esta forma se hace necesaria una mejor comprensión de este fenómeno en la carcinogénesis gástrica.