MBD4

Gene Summary

Gene:MBD4; methyl-CpG binding domain 4, DNA glycosylase
Aliases: MED1
Location:3q21.3
Summary:The protein encoded by this gene is a member of a family of nuclear proteins related by the presence of a methyl-CpG binding domain (MBD). These proteins are capable of binding specifically to methylated DNA, and some members can also repress transcription from methylated gene promoters. This protein contains an MBD domain at the N-terminus that functions both in binding to methylated DNA and in protein interactions and a C-terminal mismatch-specific glycosylase domain that is involved in DNA repair. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Jan 2013]
Databases:OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:methyl-CpG-binding domain protein 4
Source:NCBIAccessed: 01 September, 2019

Ontology:

What does this gene/protein do?
Show (17)

Cancer Overview

Research Indicators

Publications Per Year (1994-2019)
Graph generated 01 September 2019 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

  • DNA Methylation
  • DNA-Binding Proteins
  • DNA (Cytosine-5-)-Methyltransferases
  • Lung Cancer
  • CpG Islands
  • DNA Repair
  • Signal Transducing Adaptor Proteins
  • DNA Damage
  • Carrier Proteins
  • Genetic Predisposition
  • DNA (Cytosine-5-)-Methyltransferase 1
  • Adenocarcinoma
  • Microsatellite Instability
  • Frameshift Mutation
  • Transfection
  • MutL Protein Homolog 1
  • Single Nucleotide Polymorphism
  • Cancer DNA
  • MutS Homolog 2 Protein
  • Gene Silencing
  • DNA Glycosylases
  • Transcription
  • Methyl-CpG-Binding Protein 2
  • Case-Control Studies
  • Histones
  • Immunohistochemistry
  • Promoter Regions
  • Prostate Cancer
  • Base Pair Mismatch
  • Neoplasm Proteins
  • Proto-Oncogene Proteins
  • Chromosome 3
  • Polymerase Chain Reaction
  • DNA Mutational Analysis
  • Cancer Gene Expression Regulation
  • Phenotype
  • Endodeoxyribonucleases
  • Nuclear Proteins
  • Epigenetics
  • Colorectal Cancer
  • Messenger RNA
Tag cloud generated 01 September, 2019 using data from PubMed, MeSH and CancerIndex

Specific Cancers (3)

Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.

Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).

Latest Publications: MBD4 (cancer-related)

Cao HM, Wan Z, Wu Y, et al.
Development and internal validation of a novel model and markers to identify the candidates for lymph node metastasis in patients with prostate cancer.
Medicine (Baltimore). 2019; 98(30):e16534 [PubMed] Related Publications
BACKGROUND: High-grade prostate cancer (PCa) has a poor prognosis, and up to 15% of patients worldwide experience lymph node invasion (LNI). To further improve the prediction lymph node invasion in prostate cancer, we adopted risk scores of the genes expression based on the nomogram in guidelines.
METHODS: We analyzed clinical data from 320 PCa patients from the Cancer Genome Atlas database. Weighted gene coexpression network analysis was used to identify the genes that were significantly associated with LNI in PCa (n = 390). Analyses using the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases were performed to identify the activated signaling pathways. Univariate and multivariate logistic regression analyses were performed to identify the independent risk factors for the presence of LNI.
RESULTS: We found that patients with actual LNI and predicted LNI had the worst survival outcomes. The 7 most significant genes (CTNNAL1, ENSA, MAP6D1, MBD4, PRCC, SF3B2, TREML1) were selected for further analysis. Pathways in the cell cycle, DNA replication, oocyte meiosis, and 9 other pathways were dramatically activated during LNI in PCa. Multivariate analyses identified that the risk score (odds ratio [OR] = 1.05 for 1% increase, 95% confidence interval [CI]: 1.04-1.07, P < .001), serum PSA level, clinical stage, primary biopsy Gleason grade (OR = 2.52 for a grade increase, 95% CI: 1.27-5.22, P = .096), and secondary biopsy Gleason grade were independent predictors of LNI. A nomogram built using these predictive variables showed good calibration and a net clinical benefit, with an area under the curve (AUC) value of 90.2%.
CONCLUSIONS: In clinical practice, the application of our nomogram might contribute significantly to the selection of patients who are good candidates for surgery with extended pelvic lymph node dissection.

Lukács J, Soltész B, Penyige A, et al.
Identification of miR-146a and miR-196a-2 single nucleotide polymorphisms at patients with high-grade serous ovarian cancer.
J Biotechnol. 2019; 297:54-57 [PubMed] Related Publications
MicroRNAs play an essential role in the regulation of gene expression and tumor development. Single nucleotide polymorphism (SNP) can be observed in miRNAs and could influence gene expression. We aimed to identify miR-146a rs2910164 and miR-196a-2 rs11614913 polymorphisms in ovarian cancer patients and controls. 75 patients and 75 controls were involved. DNA was isolated from blood samples. MiR-146a rs2910164 and miR-196a-2 rs11614913 were determined by LightSnip kit. We used melting curve analysis for allele classification. Network analysis was made to find common target genes. We detected 72.67% G allele frequency of miR-146a rs2910164 in controls and 82.00% in patients group (p = 0,053). GG, GC and CC genotypes occurred with 53.33%, 38.67% and 8.00% among controls, with 65.33%, 33.33% and 1.33% among patients, (p = 0.0917). Allele C of miR-196a-2 rs11614913 occurred in 59.33% of controls and in 67.33% of patients (p = 0.15). CC, CT and TT genotypes occurred with 37.33%, 44.00%, and 18.67% frequency in controls, with 46.67%; 41.33% and 12.00% in patients (p = 0.3815). Network analysis found ATG9A, LBR, MBD4 and RUFY2 genes to be targets for both miRNAs. SNPs of miR-146a and miR-196a-2 showed no significant differences between patients and controls. More investigations are required to clarify the exact role of these SNPs in ovarian cancer.

Jung AR, Eun YG, Lee YC, et al.
Clinical Significance of CUB and Sushi Multiple Domains 1 Inactivation in Head and Neck Squamous Cell Carcinoma.
Int J Mol Sci. 2018; 19(12) [PubMed] Free Access to Full Article Related Publications
Although the genetic alteration of CUB and Sushi multiple domains 1 (CSMD1) is known to be associated with poor prognosis in several cancers, there is a lack of clinical relevance in head and neck cancer. The aim of this study was to offer insight into the clinical significance of CSMD1, utilizing a multimodal approach that leverages publicly available independent genome-wide expression datasets. CSMD1-related genes were found and analyzed to examine the clinical significance of CSMD1 inactivation in the HNSCC cohort of publicly available databases. We analyzed the frequency of somatic mutations, clinicopathologic characteristics, association with immunotherapy-related gene signatures, and the pathways of gene signatures. We found 363 CSMD1-related genes. The prognosis of the CSMD1-inactivated subgroup was poor.

Sanders MA, Chew E, Flensburg C, et al.
MBD4 guards against methylation damage and germ line deficiency predisposes to clonal hematopoiesis and early-onset AML.
Blood. 2018; 132(14):1526-1534 [PubMed] Free Access to Full Article Related Publications
The tendency of 5-methylcytosine (5mC) to undergo spontaneous deamination has had a major role in shaping the human genome, and this methylation damage remains the primary source of somatic mutations that accumulate with age. How 5mC deamination contributes to cancer risk in different tissues remains unclear. Genomic profiling of 3 early-onset acute myeloid leukemias (AMLs) identified germ line loss of MBD4 as an initiator of 5mC-dependent hypermutation. MBD4-deficient AMLs display a 33-fold higher mutation burden than AML generally, with >95% being C>T in the context of a CG dinucleotide. This distinctive signature was also observed in sporadic cancers that acquired biallelic mutations in

Ren C, Zhang G, Han F, et al.
Spatially constrained tandem bromodomain inhibition bolsters sustained repression of BRD4 transcriptional activity for TNBC cell growth.
Proc Natl Acad Sci U S A. 2018; 115(31):7949-7954 [PubMed] Free Access to Full Article Related Publications
The importance of BET protein BRD4 in gene transcription is well recognized through the study of chemical modulation of its characteristic tandem bromodomain (BrD) binding to lysine-acetylated histones and transcription factors. However, while monovalent inhibition of BRD4 by BET BrD inhibitors such as JQ1 blocks growth of hematopoietic cancers, it is much less effective generally in solid tumors. Here, we report a thienodiazepine-based bivalent BrD inhibitor, MS645, that affords spatially constrained tandem BrD inhibition and consequently sustained repression of BRD4 transcriptional activity in blocking proliferation of solid-tumor cells including a panel of triple-negative breast cancer (TNBC) cells. MS645 blocks BRD4 binding to transcription enhancer/mediator proteins MED1 and YY1 with potency superior to monovalent BET inhibitors, resulting in down-regulation of proinflammatory cytokines and genes for cell-cycle control and DNA damage repair that are largely unaffected by monovalent BrD inhibition. Our study suggests a therapeutic strategy to maximally control BRD4 activity for rapid growth of solid-tumor TNBC cells.

Zhang Y, Yang YL, Zhang FL, et al.
Epigenetic silencing of RNF144A expression in breast cancer cells through promoter hypermethylation and MBD4.
Cancer Med. 2018; 7(4):1317-1325 [PubMed] Free Access to Full Article Related Publications
Emerging evidence shows that ring finger protein 144A (RNF144A), a poorly characterized member of the Ring-between-Ring (RBR) family of E3 ubiquitin ligases, is a potential tumor suppressor gene. However, its regulatory mechanism in breast cancer remains undefined. Here, we report that RNF144A promoter contains a putative CpG island and the methylation levels of RNF144A promoter are higher in primary breast tumors than those in normal breast tissues. Consistently, RNF144A promoter methylation levels are associated with its transcriptional silencing in breast cancer cells, and treatment with DNA methylation inhibitor 5-Aza-2-deoxycytidine (AZA) reactivates RNF144A expression in cells with RNF144A promoter hypermethylation. Furthermore, genetic knockdown or pharmacological inhibition of endogenous methyl-CpG-binding domain 4 (MBD4) results in increased RNF144A expression. These findings suggest that RNF144A is epigenetically silenced in breast cancer cells by promoter hypermethylation and MBD4.

Terai H, Kitajima S, Potter DS, et al.
ER Stress Signaling Promotes the Survival of Cancer "Persister Cells" Tolerant to EGFR Tyrosine Kinase Inhibitors.
Cancer Res. 2018; 78(4):1044-1057 [PubMed] Free Access to Full Article Related Publications
An increasingly recognized component of resistance to tyrosine kinase inhibitors (TKI) involves persistence of a drug-tolerant subpopulation of cancer cells that survive despite effective eradication of the majority of the cell population. Multiple groups have demonstrated that these drug-tolerant persister cells undergo transcriptional adaptation via an epigenetic state change that promotes cell survival. Because this mode of TKI drug tolerance appears to involve transcriptional addiction to specific genes and pathways, we hypothesized that systematic functional screening of EGFR TKI/transcriptional inhibitor combination therapy would yield important mechanistic insights and alternative drug escape pathways. We therefore performed a genome-wide CRISPR/Cas9 enhancer/suppressor screen in EGFR-dependent lung cancer PC9 cells treated with erlotinib + THZ1 (CDK7/12 inhibitor) combination therapy, a combination previously shown to suppress drug-tolerant cells in this setting. As expected, suppression of multiple genes associated with transcriptional complexes (EP300, CREBBP, and MED1) enhanced erlotinib/THZ1 synergy. Unexpectedly, we uncovered nearly every component of the recently described ufmylation pathway in the synergy suppressor group. Loss of ufmylation did not affect canonical downstream EGFR signaling. Instead, absence of this pathway triggered a protective unfolded protein response associated with STING upregulation, promoting protumorigenic inflammatory signaling but also unique dependence on Bcl-xL. These data reveal that dysregulation of ufmylation and ER stress comprise a previously unrecognized TKI drug tolerance pathway that engages survival signaling, with potentially important therapeutic implications.

Yang Y, Leonard M, Zhang Y, et al.
HER2-Driven Breast Tumorigenesis Relies upon Interactions of the Estrogen Receptor with Coactivator MED1.
Cancer Res. 2018; 78(2):422-435 [PubMed] Free Access to Full Article Related Publications
Studies of the estrogen receptor (ER) coactivator protein Mediator subunit 1 (MED1) have revealed its specific roles in pubertal mammary gland development and potential contributions to breast tumorigenesis, based on coamplification of MED1 and HER2 in certain breast cancers. In this study, we generated a mouse model of mammary tumorigenesis harboring the MMTV-HER2 oncogene and mutation of MED1 to evaluate its role in HER2-driven tumorigenesis. MED1 mutation in its ER-interacting LxxLL motifs was sufficient to delay tumor onset and to impair tumor growth, metastasis, and cancer stem-like cell formation in this model. Mechanistic investigations revealed that MED1 acted directly to regulate ER signaling through the downstream IGF1 pathway but not the AREG pathway. Our findings show that MED1 is critical for HER2-driven breast tumorigenesis, suggesting its candidacy as a disease-selective therapeutic target.

Wojtczyk-Miaskowska A, Presler M, Michajlowski J, et al.
Gene Expression, DNA Methylation and Prognostic Significance of DNA Repair Genes in Human Bladder Cancer.
Cell Physiol Biochem. 2017; 42(6):2404-2417 [PubMed] Related Publications
BACKGROUND/AIMS: This study investigated the gene expression and DNA methylation of selected DNA repair genes (MBD4, TDG, MLH1, MLH3) and DNMT1 in human bladder cancer in the context of pathophysiological and prognostic significance.
METHODS: To determine the relationship between the gene expression pattern, global methylation and promoter methylation status, we performed real-time PCR to quantify the mRNA of selected genes in 50 samples of bladder cancer and adjacent non-cancerous tissue. The methylation status was analyzed by methylation-specific polymerase chain reaction (MSP) or digestion of genomic DNA with a methylation-sensitive restriction enzyme and PCR with gene-specific primers (MSRE-PCR). The global DNA methylation level was measured using the antibody-based 5-mC detection method.
RESULTS: The relative levels of mRNA for MBD4, MLH3, and MLH1 were decreased in 28% (14/50), 34% (17/50) and 36% (18/50) of tumor samples, respectively. The MBD4 mRNA expression was decreased in 46% of non-muscle invasive tumors (Ta/T1) compared with 11% found in muscle invasive tumors (T2-T4) (P<0.003). Analysis of mRNA expression for TDG did not show any significant differences between Ta/T1 and T2-T4 tumors. The frequency of increased DNMT1 mRNA expression was higher in T2-T4 (52%) comparing to Ta/T1 (16%). The overall methylation rates in tumor tissue were 18% for MBD4, 25% for MLH1 and there was no evidence of MLH3 promoter methylation. High grade tumors had significantly lower levels of global DNA methylation (P=0.04). There was a significant association between shorter survival and increased expression of DNMT1 mRNA (P=0.002), decreased expression of MLH1 mRNA (P=0.032) and the presence of MLH1 promoter methylation (P=0.006).
CONCLUSION: This study highlights the importance of DNA repair pathways and provides the first evidence of the role of MBD4 and MLH3 in bladder cancer. In addition, our findings suggest that DNMT1 mRNA and MLH1 mRNA expression, as well as the status of MLH1 promoter methylation, are attractive prognostic markers in this pathology.

Triki M, Lapierre M, Cavailles V, Mokdad-Gargouri R
Expression and role of nuclear receptor coregulators in colorectal cancer.
World J Gastroenterol. 2017; 23(25):4480-4490 [PubMed] Free Access to Full Article Related Publications
Colorectal cancer (CRC) is one of the most common human cancers and the cause of about 700000 deaths per year worldwide. Deregulation of the WNT/β-catenin pathway is a key event in CRC initiation. This pathway interacts with other nuclear signaling pathways, including members of the nuclear receptor superfamily and their transcription coregulators. In this review, we provide an overview of the literature dealing with the main coactivators (NCoA-1 to 3, NCoA-6, PGC1-α, p300, CREBBP and MED1) and corepressors (N-CoR1 and 2, NRIP1 and MTA1) of nuclear receptors and summarize their links with the WNT/β-catenin signaling cascade, their expression in CRC and their role in intestinal physiopathology.

Iżykowska K, Przybylski GK, Gand C, et al.
Genetic rearrangements result in altered gene expression and novel fusion transcripts in Sézary syndrome.
Oncotarget. 2017; 8(24):39627-39639 [PubMed] Free Access to Full Article Related Publications
Sézary syndrome (SS) is an aggressive, leukemic cutaneous T-cell lymphoma variant. Molecular pathogenesis of SS is still unclear despite many studies on genetic alterations, gene expression and epigenetic regulations. Through whole genome and transcriptome next generation sequencing nine Sézary syndrome patients were analyzed in terms of copy number variations and rearrangements affecting gene expression. Recurrent copy number variations were detected within 8q (MYC, TOX), 17p (TP53, NCOR1), 10q (PTEN, FAS), 2p (DNMT3A), 11q (USP28), 9p (CAAP1), but no recurrent rearrangements were identified. However, expression of five genes involved in rearrangements (TMEM244, EHD1, MTMR2, RNF123 and TOX) was altered in all patients. Fifteen rearrangements detected in Sézary syndrome patients and SeAx resulted in an expression of new fusion transcripts, nine of them were in frame (EHD1-CAPN12, TMEM66-BAIAP2, MBD4-PTPRC, PTPRC-CPN2, MYB-MBNL1, TFG-GPR128, MAP4K3-FIGLA, DCP1A-CCL27, MBNL1-KIAA2018) and five resulted in ectopic expression of fragments of genes not expressed in normal T-cells (BAIAP2, CPN2, GPR128, CAPN12, FIGLA). Our results not only underscored the genomic complexity of the Sézary cancer cell genome but also showed an unpreceded large variety of novel gene rearrangements resulting in fusions transcripts and ectopically expressed genes.

Jiang M, Zhong T, Zhang W, et al.
Reduced expression of miR‑205‑5p promotes apoptosis and inhibits proliferation and invasion in lung cancer A549 cells by upregulation of ZEB2 and downregulation of erbB3.
Mol Med Rep. 2017; 15(5):3231-3238 [PubMed] Related Publications
Previous studies have demonstrated that microRNA (miR)-205-5p expression is significantly increased in non‑small cell lung cancer tissues and is associated with tumor differentiation grade. The aim of the present study was to explore the effects of miR‑205‑5p on viability, apoptosis and invasion of lung cancer A549 cells. The hsa‑miR‑205‑5p small interfering RNA (siRNA) inhibitor was transfected into A549 cells and expression of miR‑205‑5p was detected by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR). Cell viability, apoptosis and invasion were assayed by Cell Counting kit‑8, Annexin V/propidium iodide double staining and Transwell assay, respectively. Target genes of miR‑205‑5p were predicted using bioinformatics analysis. Expression of mRNA and protein levels of candidate target genes following miR‑205‑5p inhibition were detected using RT‑qPCR and western blot analysis respectively. The results demonstrated that relative survival rates of A549 cells were significantly inhibited in miR‑205‑5p siRNA‑transfected cells at 24 and 48 h compared with control cells. Apoptosis was markedly increased in the miR‑205‑5p siRNA cells compared with control cells. The number of invaded cells following miR‑205‑5p siRNA silencing was significantly decreased compared with control cells. Bioinformatics analysis revealed that erb‑B2 receptor kinase 3 (erbB3), zinc finger E‑box binding homeobox 2 (ZEB2), clathrin heavy chain (CLTC) and mediator complex subunit 1 (MED1) may be potential target genes of miR‑205‑5p. Reduced expression of miR‑205‑5p significantly increased the expression of ZEB2 mRNA and protein, inhibited the expression of erbB3 protein, but had no significant effect on the expression levels of CLTC and MED1. In summary, reduced expression of miR‑205‑5p promoted apoptosis and inhibited proliferation and invasion in lung cancer A549 cells through upregulation of ZEB2 and downregulation of erbB3. The present results suggested that the increased miR‑205‑5p expression observed in non‑small cell lung cancer tissues may contribute to increased proliferation and invasion of lung cancer cells and thus to cancer progression.

Mansouri S, Naghavi-Al-Hosseini F, Farahmand L, Majidzadeh-A K
MED1 may explain the interaction between receptor tyrosine kinases and ERα66 in the complicated network of Tamoxifen resistance.
Eur J Pharmacol. 2017; 804:78-81 [PubMed] Related Publications
According to the American Society of Clinical Oncology or ASCO's clinical practice guidelines, administration of Tamoxifen for hormone receptor positive patients improved outcomes. However, many studies have been conducted in this issue, with the rise of Tamoxifen resistance in recent decades. There are many alternative growth cascades that are activated in Tamoxifen resistant cells. The most common and well characterized components of such a resistant network are receptor tyrosine kinases, or RTKs, which can influence many other cellular processes. The interactions between estrogen dependent and independent pathways further complicate the networking. MED1, as a member of a mediator complex, which is activated by RTK growth pathways, plays role in co-activating ERα66 to transcribe genes and enhance cellular proliferation. Herein, we will discuss MED1, a novel biomarker which can explain how RTKs interact with ERα66 which results in Tamoxifen resistance.

Zawistowski JS, Bevill SM, Goulet DR, et al.
Enhancer Remodeling during Adaptive Bypass to MEK Inhibition Is Attenuated by Pharmacologic Targeting of the P-TEFb Complex.
Cancer Discov. 2017; 7(3):302-321 [PubMed] Free Access to Full Article Related Publications
Targeting the dysregulated BRAF-MEK-ERK pathway in cancer has increasingly emerged in clinical trial design. Despite clinical responses in specific cancers using inhibitors targeting BRAF and MEK, resistance develops often involving nongenomic adaptive bypass mechanisms. Inhibition of MEK1/2 by trametinib in patients with triple-negative breast cancer (TNBC) induced dramatic transcriptional responses, including upregulation of receptor tyrosine kinases (RTK) comparing tumor samples before and after one week of treatment. In preclinical models, MEK inhibition induced genome-wide enhancer formation involving the seeding of BRD4, MED1, H3K27 acetylation, and p300 that drives transcriptional adaptation. Inhibition of the P-TEFb-associated proteins BRD4 and CBP/p300 arrested enhancer seeding and RTK upregulation. BRD4 bromodomain inhibitors overcame trametinib resistance, producing sustained growth inhibition in cells, xenografts, and syngeneic mouse TNBC models. Pharmacologic targeting of P-TEFb members in conjunction with MEK inhibition by trametinib is an effective strategy to durably inhibit epigenomic remodeling required for adaptive resistance.

Talhaoui I, Matkarimov BT, Tchenio T, et al.
Aberrant base excision repair pathway of oxidatively damaged DNA: Implications for degenerative diseases.
Free Radic Biol Med. 2017; 107:266-277 [PubMed] Related Publications
In cellular organisms composition of DNA is constrained to only four nucleobases A, G, T and C, except for minor DNA base modifications such as methylation which serves for defence against foreign DNA or gene expression regulation. Interestingly, this severe evolutionary constraint among other things demands DNA repair systems to discriminate between regular and modified bases. DNA glycosylases specifically recognize and excise damaged bases among vast majority of regular bases in the base excision repair (BER) pathway. However, the mismatched base pairs in DNA can occur from a spontaneous conversion of 5-methylcytosine to thymine and DNA polymerase errors during replication. To counteract these mutagenic threats to genome stability, cells evolved special DNA repair systems that target the non-damaged DNA strand in a duplex to remove mismatched regular DNA bases. Mismatch-specific adenine- and thymine-DNA glycosylases (MutY/MUTYH and TDG/MBD4, respectively) initiated BER and mismatch repair (MMR) pathways can recognize and remove normal DNA bases in mismatched DNA duplexes. Importantly, in DNA repair deficient cells bacterial MutY, human TDG and mammalian MMR can act in the aberrant manner: MutY and TDG removes adenine and thymine opposite misincorporated 8-oxoguanine and damaged adenine, respectively, whereas MMR removes thymine opposite to O

Wang X, Dong C, Yin J, et al.
Tagging polymorphisms of methyl-CpG binding domain 4 and gastric cardiac adenocarcinoma risk in a Chinese population.
Dis Esophagus. 2017; 30(2):1-6 [PubMed] Related Publications
Potential effects of genetic factors on carcinogenesis of gastric cardiac adenocarcinoma (GCA) may exist. The present experiment specifically evaluated the genetic influence of single nucleotide in methyl-CpG binding domain 4 (MBD4) on GCA tumorigenesis. A case-control experiment based on hospital recruited 330 GCA patients and 608 non-cancer patients was carried out. We employed ligation detection reaction method to detect the genotypes. The results revealed that MBD4 rs3138373, rs2005618, and rs3138355 mutations had no significant association with the risk of GCA. However, a lower risk of GCA presented in male patients who carried the MBD4 rs3138355 G>A polymorphic loci by the stratified analyses. In general, The MBD4 gene polymorphism could not influence GCA hereditary predisposition. Nevertheless, whether the finding learned from our experiment could apply to other ethnic groups will remain vague until future multicenter studies further test and verify our conclusions.

Mahalingaiah PK, Ponnusamy L, Singh KP
Oxidative stress-induced epigenetic changes associated with malignant transformation of human kidney epithelial cells.
Oncotarget. 2017; 8(7):11127-11143 [PubMed] Free Access to Full Article Related Publications
Renal Cell Carcinoma (RCC) in humans is positively influenced by oxidative stress status in kidneys. We recently reported that adaptive response to low level of chronic oxidative stress induces malignant transformation of immortalized human renal tubular epithelial cells. Epigenetic alterations in human RCC are well documented, but its role in oxidative stress-induced malignant transformation of kidney cells is not known. Therefore, the objective of this study was to evaluate the potential role of epigenetic changes in chronic oxidative stress-induced malignant transformation of HK-2, human renal tubular epithelial cells. The results revealed aberrant expression of epigenetic regulatory genes involved in DNA methylation (DNMT1, DNMT3a and MBD4) and histone modifications (HDAC1, HMT1 and HAT1) in HK-2 cells malignantly transformed by chronic oxidative stress. Additionally, both in vitro soft agar assay and in vivo nude mice study showing decreased tumorigenic potential of malignantly transformed HK-2 cells following treatment with DNA de-methylating agent 5-aza 2' dC further confirmed the crucial role of DNA hypermethyaltion in oxidative stress-induced malignant transformation. Changes observed in global histone H3 acetylation (H3K9, H3K18, H3K27 and H3K14) and decrease in phospho-H2AX (Ser139) also suggest potential role of histone modifications in increased survival and malignant transformation of HK-2 cells by oxidative stress. In summary, the results of this study suggest that epigenetic reprogramming induced by low levels of oxidative stress act as driver for malignant transformation of kidney epithelial cells. Findings of this study are highly relevant in potential clinical application of epigenetic-based therapeutics for treatments of kidney cancers.

Tanaka S, Maekawa A, Matsubara L, et al.
Periostin supports hematopoietic progenitor cells and niche-dependent myeloblastoma cells in vitro.
Biochem Biophys Res Commun. 2016; 478(4):1706-12 [PubMed] Free Access to Full Article Related Publications
The expression of extracellular matrix protein periostin (POSTN) was attenuated in Med1(-/-) mouse embryonic fibroblasts (MEFs), which exhibited a decreased capability to support hematopoietic progenitor cells (HPCs) in vitro. When bone marrow (BM) cells were cocultured with mitomycin C-treated Med1(+/+) MEFs, or OP-9 or MS-5 BM stromal cells, in the presence of anti-POSTN antibody, the growth of BM cells and number of long-term culture-initiating cells (LTC-ICs) were attenuated. When BM cells were cocultured with Med1(-/-) MEFs in the presence of recombinant POSTN, the growth of BM cells and the number of LTC-ICs were restored. Moreover, antibody-mediated blockage of stromal cells-derived POSTN markedly reduced the growth and cobblestone formation, a leukemic stem cell feature, of stromal cell-dependent MB-1 myeloblastoma cells. POSTN was expressed both in BM cells and variably in different BM stromal cells. Expression in the latter cells was increased by physical interaction with hematopoietic cells. The receptor for POSTN, integrin αvβ3, was expressed abundantly in BM stromal cells. The addition of recombinant POSTN to BM stromal cells induced intracellular signaling downstream of integrin αvβ3. These results suggest that stromal cell POSTN supports both normal HPCs and leukemia-initiating cells in vitro, at least in part, indirectly by acting on stromal cells in an autocrine or paracrine manner.

Zhao J, Li X, Yao Q, et al.
RWCFusion: identifying phenotype-specific cancer driver gene fusions based on fusion pair random walk scoring method.
Oncotarget. 2016; 7(38):61054-61068 [PubMed] Free Access to Full Article Related Publications
While gene fusions have been increasingly detected by next-generation sequencing (NGS) technologies based methods in human cancers, these methods have limitations in identifying driver fusions. In addition, the existing methods to identify driver gene fusions ignored the specificity among different cancers or only considered their local rather than global topology features in networks. Here, we proposed a novel network-based method, called RWCFusion, to identify phenotype-specific cancer driver gene fusions. To evaluate its performance, we used leave-one-out cross-validation in 35 cancers and achieved a high AUC value 0.925 for overall cancers and an average 0.929 for signal cancer. Furthermore, we classified 35 cancers into two classes: haematological and solid, of which the haematological got a highly AUC which is up to 0.968. Finally, we applied RWCFusion to breast cancer and found that top 13 gene fusions, such as BCAS3-BCAS4, NOTCH-NUP214, MED13-BCAS3 and CARM-SMARCA4, have been previously proved to be drivers for breast cancer. Additionally, 8 among the top 10 of the remaining candidate gene fusions, such as SULF2-ZNF217, MED1-ACSF2, and ACACA-STAC2, were inferred to be potential driver gene fusions of breast cancer by us.

Zhou B, Wang L, Zhang S, et al.
INO80 governs superenhancer-mediated oncogenic transcription and tumor growth in melanoma.
Genes Dev. 2016; 30(12):1440-53 [PubMed] Free Access to Full Article Related Publications
Superenhancers (SEs) are large genomic regions with a high density of enhancer marks. In cancer, SEs are found near oncogenes and dictate cancer gene expression. However, how oncogenic SEs are regulated remains poorly understood. Here, we show that INO80, a chromatin remodeling complex, is required for SE-mediated oncogenic transcription and tumor growth in melanoma. The expression of Ino80, the SWI/SNF ATPase, is elevated in melanoma cells and patient melanomas compared with normal melanocytes and benign nevi. Furthermore, Ino80 silencing selectively inhibits melanoma cell proliferation, anchorage-independent growth, tumorigenesis, and tumor maintenance in mouse xenografts. Mechanistically, Ino80 occupies >90% of SEs, and its occupancy is dependent on transcription factors such as MITF and Sox9. Ino80 binding reduces nucleosome occupancy and facilitates Mediator recruitment, thus promoting oncogenic transcription. Consistently, genes co-occupied by Ino80 and Med1 are selectively expressed in melanomas compared with melanocytes. Together, our results reveal an essential role of INO80-dependent chromatin remodeling in SE function and suggest a novel strategy for disrupting SEs in cancer treatment.

Suzuki S, Iwaizumi M, Tseng-Rogenski S, et al.
Production of truncated MBD4 protein by frameshift mutation in DNA mismatch repair-deficient cells enhances 5-fluorouracil sensitivity that is independent of hMLH1 status.
Cancer Biol Ther. 2016; 17(7):760-8 [PubMed] Free Access to Full Article Related Publications
Methyl-CpG binding domain protein 4 (MBD4) is a DNA glycosylase that can remove 5-fluorodeoxyuracil from DNA as well as repair T:G or U:G mismatches. MBD4 is a target for frameshift mutation with DNA mismatch repair (MMR) deficiency, creating a truncated MBD4 protein (TruMBD4) that lacks its glycosylase domain. Here we show that TruMBD4 plays an important role for enhancing 5-fluorouracil (5FU) sensitivity in MMR-deficient colorectal cancer cells. We found biochemically that TruMBD4 binds to 5FU incorporated into DNA with higher affinity than MBD4. TruMBD4 reduced the 5FU affinity of the MMR recognition complexes that determined 5FU sensitivity by previous reports, suggesting other mechanisms might be operative to trigger cytotoxicity. To analyze overall 5FU sensitivity with TruMBD4, we established TruMBD4 overexpression in hMLH1-proficient or -deficient colorectal cancer cells followed by treatment with 5FU. 5FU-treated TruMBD4 cells demonstrated diminished growth characteristics compared to controls, independently of hMLH1 status. Flow cytometry revealed more 5FU-treated TruMBD4 cells in S phase than controls. We conclude that patients with MMR-deficient cancers, which show characteristic resistance to 5FU therapy, may be increased for 5FU sensitivity via secondary frameshift mutation of the base excision repair gene MBD4.

Budczies J, Pfarr N, Stenzinger A, et al.
Ioncopy: a novel method for calling copy number alterations in amplicon sequencing data including significance assessment.
Oncotarget. 2016; 7(11):13236-47 [PubMed] Free Access to Full Article Related Publications
Recently, it has been demonstrated that calling of copy number alterations (CNAs) from amplicon sequencing (AS) data is feasible. Most approaches, however, require non-tumor (germline) DNA for data normalization. Here, we present the method Ioncopy for CNA detection which requires no normal controls and includes a significance assessment for each detected alteration.Ioncopy was evaluated in a cohort of 184 clinically annotated breast carcinomas. A total number of 252 amplifications were detected, of which 183 (72.6%) could be validated by a call of an additional amplicon interrogating the same gene. Moreover, a total number of 33 deletions were found, whereof 27 (81.8%) could be validated. Analyzing the 16 most frequently amplified genes, validation rates of over 89% could be achieved for 11 of these genes. 11 of the top 16 genes showed significant overexpression in the amplified tumors. 89.5% of the HER2-amplified tumors were GRB7 and STARD3 co-amplified, whereas 68.4% of the HER2-amplified tumors had additional MED1 amplifications. Correlations between CNAs measured by amplicons in HER2 exons 19, 20 and 21 were strong (all R > 0.93). AS based detection of HER2 amplifications had a sensitivity of 90.0% and a specificity of 98.8% compared to the gold standard of HER2 immunohistochemistry combined with in situ hybridization.In summary, we developed and validated a novel method for detection and significance assessment of CNAs in amplicon sequencing data. Using Ioncopy, AS offers a straightforward and efficient approach to simultaneously analyze gene amplifications and gene deletions together with simple somatic mutations in a single assay.

Sunkel B, Wu D, Chen Z, et al.
Integrative analysis identifies targetable CREB1/FoxA1 transcriptional co-regulation as a predictor of prostate cancer recurrence.
Nucleic Acids Res. 2016; 44(9):4105-22 [PubMed] Free Access to Full Article Related Publications
Identifying prostate cancer-driving transcription factors (TFs) in addition to the androgen receptor promises to improve our ability to effectively diagnose and treat this disease. We employed an integrative genomics analysis of master TFs CREB1 and FoxA1 in androgen-dependent prostate cancer (ADPC) and castration-resistant prostate cancer (CRPC) cell lines, primary prostate cancer tissues and circulating tumor cells (CTCs) to investigate their role in defining prostate cancer gene expression profiles. Combining genome-wide binding site and gene expression profiles we define CREB1 as a critical driver of pro-survival, cell cycle and metabolic transcription programs. We show that CREB1 and FoxA1 co-localize and mutually influence each other's binding to define disease-driving transcription profiles associated with advanced prostate cancer. Gene expression analysis in human prostate cancer samples found that CREB1/FoxA1 target gene panels predict prostate cancer recurrence. Finally, we showed that this signaling pathway is sensitive to compounds that inhibit the transcription co-regulatory factor MED1. These findings not only reveal a novel, global transcriptional co-regulatory function of CREB1 and FoxA1, but also suggest CREB1/FoxA1 signaling is a targetable driver of prostate cancer progression and serves as a biomarker of poor clinical outcomes.

Shu S, Lin CY, He HH, et al.
Response and resistance to BET bromodomain inhibitors in triple-negative breast cancer.
Nature. 2016; 529(7586):413-417 [PubMed] Free Access to Full Article Related Publications
Triple-negative breast cancer (TNBC) is a heterogeneous and clinically aggressive disease for which there is no targeted therapy. BET bromodomain inhibitors, which have shown efficacy in several models of cancer, have not been evaluated in TNBC. These inhibitors displace BET bromodomain proteins such as BRD4 from chromatin by competing with their acetyl-lysine recognition modules, leading to inhibition of oncogenic transcriptional programs. Here we report the preferential sensitivity of TNBCs to BET bromodomain inhibition in vitro and in vivo, establishing a rationale for clinical investigation and further motivation to understand mechanisms of resistance. In paired cell lines selected for acquired resistance to BET inhibition from previously sensitive TNBCs, we failed to identify gatekeeper mutations, new driver events or drug pump activation. BET-resistant TNBC cells remain dependent on wild-type BRD4, which supports transcription and cell proliferation in a bromodomain-independent manner. Proteomic studies of resistant TNBC identify strong association with MED1 and hyper-phosphorylation of BRD4 attributable to decreased activity of PP2A, identified here as a principal BRD4 serine phosphatase. Together, these studies provide a rationale for BET inhibition in TNBC and present mechanism-based combination strategies to anticipate clinical drug resistance.

Tricarico R, Cortellino S, Riccio A, et al.
Involvement of MBD4 inactivation in mismatch repair-deficient tumorigenesis.
Oncotarget. 2015; 6(40):42892-904 [PubMed] Free Access to Full Article Related Publications
The DNA glycosylase gene MBD4 safeguards genomic stability at CpG sites and is frequently mutated at coding poly-A tracks in mismatch repair (MMR)-defective colorectal tumors (CRC). Mbd4 biallelic inactivation in mice provided conflicting results as to its role in tumorigenesis. Thus, it is unclear whether MBD4 alterations are only secondary to MMR defects without functional consequences or can contribute to the mutator phenotype. We investigated MBD4 variants in a large series of hereditary/familial and sporadic CRC cases. Whereas MBD4 frameshifts were only detected in tumors, missense variants were found in both normal and tumor DNA. In CRC with double-MBD4/MMR and single-MBD4 variants, transition mutation frequency was increased, indicating that MBD4 defects may affect the mutational landscape independently of MMR defect. Mbd4-deficient mice showed reduced survival when combined with Mlh1-/- genotype. Taken together, these data suggest that MBD4 inactivation may contribute to tumorigenesis, acting as a modifier of MMR-deficient cancer phenotype.

Nilsson EM, Laursen KB, Whitchurch J, et al.
MiR137 is an androgen regulated repressor of an extended network of transcriptional coregulators.
Oncotarget. 2015; 6(34):35710-25 [PubMed] Free Access to Full Article Related Publications
Androgens and the androgen receptor (AR) play crucial roles in male development and the pathogenesis and progression of prostate cancer (PCa). The AR functions as a ligand dependent transcription factor which recruits multiple enzymatically distinct epigenetic coregulators to facilitate transcriptional regulation in response to androgens. Over-expression of AR coregulators is implicated in cancer. We have shown that over-expression of KDM1A, an AR coregulator, contributes to PCa recurrence by promoting VEGFA expression. However the mechanism(s) whereby AR coregulators are increased in PCa remain poorly understood. In this study we show that the microRNA hsa-miR-137 (miR137) tumor suppressor regulates expression of an extended network of transcriptional coregulators including KDM1A/LSD1/AOF1, KDM2A/JHDM1A/FBXL11, KDM4A/JMJD2A, KDM5B JARID1B/PLU1, KDM7A/JHDM1D/PHF8, MED1/TRAP220/DRIP205 and NCoA2/SRC2/TIF2. We show that expression of miR137 is increased by androgen in LnCaP androgen PCa responsive cells and that the miR137 locus is epigenetically silenced in androgen LnCaP:C4-2 and PC3 independent PCa cells. In addition, we found that restoration of miR137 expression down-regulates expression of VEGFA, an AR target gene, which suggests a role of miR137 loss also in cancer angiogenesis. Finally we show functional inhibition of miR137 function enhanced androgen induction of PSA/KLK3 expression. Our data indicate that miR137 functions as an androgen regulated suppressor of androgen signaling by modulating expression of an extended network of transcriptional coregulators. Therefore, we propose that epigenetic silencing of miR137 is an important event in promoting androgen signaling during prostate carcinogenesis and progression.

Kämpjärvi K, Kim NH, Keskitalo S, et al.
Somatic MED12 mutations in prostate cancer and uterine leiomyomas promote tumorigenesis through distinct mechanisms.
Prostate. 2016; 76(1):22-31 [PubMed] Related Publications
BACKGROUND: Mediator is a multiprotein interface between eukaryotic gene-specific transcription factors and RNA polymerase II. Mutations in exon 2 of the gene encoding MED12, a key subunit of the regulatory kinase module in Mediator, are extremely frequent in uterine leiomyomas, breast fibroadenomas, and phyllodes tumors. These mutations disrupt kinase module interactions and lead to diminished Mediator-associated kinase activity. MED12 mutations in exon 26, resulting in a substitution of leucine 1224 to phenylalanine (L1224F), have been recurrently observed in prostate cancer.
METHODS: To elucidate the molecular mechanisms leading to tumorigenesis in prostate cancer, we analyzed global interaction profiles of wild-type and L1224F mutant MED12 with quantitative affinity purification-mass spectrometry (AP-MS). Immunoprecipitation and kinase activity assay were used to further assess the interactions between Mediator complex subunits and kinase activity. The presence of L1224F mutation was analyzed in altogether 877 samples representing prostate hyperplasia, prostate cancer, and various tumor types in which somatic MED12 mutations have previously been observed.
RESULTS: In contrast to N-terminal MED12 mutations observed in uterine leiomyomas, the L1224F mutation compromises neither the interaction of MED12 with kinase module subunits Cyclin C and CDK8/19 nor Mediator-associated CDK activity. Instead, the L1224F mutation was shown to affect interactions between MED12 and other Mediator components (MED1, MED13, MED13L, MED14, MED15, MED17, and MED24). Mutation screening revealed one mutation in a Finnish (Caucasian) prostate cancer patient, whereas no mutations in any other tumor type were observed.
CONCLUSIONS: Specific somatic MED12 mutations in prostate cancer and uterine leiomyomas accumulate in two separate regions of the gene and promote tumorigenesis through clearly distinct mechanisms.

Ma R, Wang C, Wang J, et al.
miRNA-mRNA Interaction Network in Non-small Cell Lung Cancer.
Interdiscip Sci. 2016; 8(3):209-19 [PubMed] Related Publications
MicroRNAs (miRNAs) are small RNA molecules, about 20-25 nucleotides in length. They repress or degrade messenger RNA (mRNA) translation, which are involved in human cancer. In this study based on paired miRNA and mRNA expression profiles of non-small cell lung cancer samples, we constructed and analyzed miRNA-mRNA interaction network via several bioinformatics softwares and platforms. This integrative network is comprised of 249 nodes for mRNA, 90 nodes for miRNA and 290 edges that show regulations between target genes and miRNAs. The three miR-1207-5p, miR-1228* and miR-939 are the most connected miRNA that regulated a large number of genes. ST8SIA2, MED1 and HDAC4, SPN, which are targeted by multiple miRNAs and located in the center of the network, are involved in both lung cancer and nervous system via functional annotation analysis. Such a global interaction network of miRNA-mRNA in lung cancer will contribute to refining miRNA target predictions and developing novel therapeutic candidates.

Hensel J, Duex JE, Owens C, et al.
Patient Mutation Directed shRNA Screen Uncovers Novel Bladder Tumor Growth Suppressors.
Mol Cancer Res. 2015; 13(9):1306-15 [PubMed] Free Access to Full Article Related Publications
UNLABELLED: Next-generation sequencing (NGS) of human bladder cancer has revealed many gene alterations compared with normal tissue, with most being predicted to be "loss of function." However, given the high number of alterations, evaluating the functional impact of each is impractical. Here, we develop and use a high-throughput, in vivo strategy to determine which alterations are loss of function in tumor growth suppressors. Genes reported as altered by NGS in bladder cancer patients were bioinformatically processed by MutationTaster and MutationAssessor, with 283 predicted as loss of function. An shRNA lentiviral library targeting these genes was transduced into T24 cells, a nontumorigenic human bladder cancer cell line, followed by injection into mice. Tumors that arose were sequenced and the dominant shRNA constructs were found to target IQGAP1, SAMD9L, PCIF1, MED1, and KATNAL1 genes. In vitro validation experiments revealed that shRNA molecules directed at IQGAP1 showed the most profound increase in anchorage-independent growth of T24 cells. The clinical relevance of IQGAP1 as a tumor growth suppressor is supported by the finding that its expression is lower in bladder cancer compared with benign patient urothelium in multiple independent datasets. Lower IQGAP1 protein expression associated with higher tumor grade and decreased patient survival. Finally, depletion of IQGAP1 leads to increased TGFBR2 with TGFβ signaling, explaining in part how reduced IQGAP1 promotes tumor growth. These findings suggest IQGAP1 is a bladder tumor growth suppressor that works via modulating TGFβ signaling and is a potentially clinically useful biomarker.
IMPLICATIONS: This study used gene mutation information from patient-derived bladder tumor specimens to inform the development of a screen used to identify novel tumor growth suppressors. This included identification of the protein IQGAP1 as a potent bladder cancer growth suppressor.

Lehmann R, Childs L, Thomas P, et al.
Assembly of a comprehensive regulatory network for the mammalian circadian clock: a bioinformatics approach.
PLoS One. 2015; 10(5):e0126283 [PubMed] Free Access to Full Article Related Publications
By regulating the timing of cellular processes, the circadian clock provides a way to adapt physiology and behaviour to the geophysical time. In mammals, a light-entrainable master clock located in the suprachiasmatic nucleus (SCN) controls peripheral clocks that are present in virtually every body cell. Defective circadian timing is associated with several pathologies such as cancer and metabolic and sleep disorders. To better understand the circadian regulation of cellular processes, we developed a bioinformatics pipeline encompassing the analysis of high-throughput data sets and the exploitation of published knowledge by text-mining. We identified 118 novel potential clock-regulated genes and integrated them into an existing high-quality circadian network, generating the to-date most comprehensive network of circadian regulated genes (NCRG). To validate particular elements in our network, we assessed publicly available ChIP-seq data for BMAL1, REV-ERBα/β and RORα/γ proteins and found strong evidence for circadian regulation of Elavl1, Nme1, Dhx6, Med1 and Rbbp7 all of which are involved in the regulation of tumourigenesis. Furthermore, we identified Ncl and Ddx6, as targets of RORγ and REV-ERBα, β, respectively. Most interestingly, these genes were also reported to be involved in miRNA regulation; in particular, NCL regulates several miRNAs, all involved in cancer aggressiveness. Thus, NCL represents a novel potential link via which the circadian clock, and specifically RORγ, regulates the expression of miRNAs, with particular consequences in breast cancer progression. Our findings bring us one step forward towards a mechanistic understanding of mammalian circadian regulation, and provide further evidence of the influence of circadian deregulation in cancer.

Disclaimer: This site is for educational purposes only; it can not be used in diagnosis or treatment.

Cite this page: Cotterill SJ. MBD4, Cancer Genetics Web: http://www.cancer-genetics.org/MBD4.htm Accessed:

Creative Commons License
This page in Cancer Genetics Web by Simon Cotterill is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
Note: content of abstracts copyright of respective publishers - seek permission where appropriate.

 [Home]    Page last revised: 01 September, 2019     Cancer Genetics Web, Established 1999