Gene Summary

Gene:MAF; MAF bZIP transcription factor
Aliases: CCA4, AYGRP, c-MAF, CTRCT21
Summary:The protein encoded by this gene is a DNA-binding, leucine zipper-containing transcription factor that acts as a homodimer or as a heterodimer. Depending on the binding site and binding partner, the encoded protein can be a transcriptional activator or repressor. This protein plays a role in the regulation of several cellular processes, including embryonic lens fiber cell development, increased T-cell susceptibility to apoptosis, and chondrocyte terminal differentiation. Defects in this gene are a cause of juvenile-onset pulverulent cataract as well as congenital cerulean cataract 4 (CCA4). Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jan 2010]
Databases:VEGA, OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:transcription factor Maf
Source:NCBIAccessed: 11 March, 2017


What does this gene/protein do?
Show (16)

Cancer Overview

Research Indicators

Publications Per Year (1992-2017)
Graph generated 11 March 2017 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.

  • Disease Progression
  • Messenger RNA
  • Gene Expression Profiling
  • Prostate Cancer
  • Case-Control Studies
  • Haplotypes
  • Chromosome Aberrations
  • Oligonucleotide Array Sequence Analysis
  • Multiple Myeloma
  • Immunoglobulin Heavy Chains
  • Base Sequence
  • Chromosome 16
  • MAF
  • Neoplastic Cell Transformation
  • MAFB
  • Proto-Oncogene Proteins c-maf
  • Mutation
  • DNA-Binding Proteins
  • Genotype
  • MicroRNAs
  • Genetic Variation
  • Ubiquitin-Protein Ligases
  • Staging
  • Sex Factors
  • Linkage Disequilibrium
  • Alleles
  • Promoter Regions
  • Molecular Sequence Data
  • Asian Continental Ancestry Group
  • Genome-Wide Association Study
  • Cancer Gene Expression Regulation
  • Cyclins
  • Translocation
  • Reproducibility of Results
  • Biomarkers, Tumor
  • FISH
  • Genetic Predisposition
  • Genetic Association Studies
  • Chromosome 14
  • Breast Cancer
Tag cloud generated 11 March, 2017 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: MAF (cancer-related)

Kern B, Coppin L, Romanet P, et al.
Multiple HABP2 variants in familial papillary thyroid carcinoma: Contribution of a group of "thyroid-checked" controls.
Eur J Med Genet. 2017; 60(3):178-184 [PubMed] Related Publications
A heterozygous germline variant in the HABP2 gene c.1601G > A (p.Gly534Glu), which negatively impacts its tumor suppressive activity in vitro, has been described in 4-14% of kindreds of European-American ancestry with familial papillary thyroid carcinoma (fPTC). But it is also found in ≈4% of Europeans and European/Americans from public databases that, however, did not provide information on the thyroid function of the controls. To get unbiased results, we decided to compare HABP2 genotypes of patients with fPTC with those of "thyroid-checked" controls. A control group consisting of 136 European patients who were thyroidectomised for medullary thyroid carcinoma and devoid of any histologically detectable PTC or follicular-deriving carcinoma was built. In parallel we recruited 20 patients with fPTC from eleven independent European kindreds. The entire coding region of HABP2 was analyzed by Sanger sequencing the germline DNAs of patients. Nucleotide variants were searched for by Snap Shot analysis in the controls. Two variants, c.1601G > A (p.Gly534Glu) and c.364C > T (p.Arg122Trp), were found in 2 and 3 patients at the heterozygous level respectively (minor allele frequency (MAF): 5.0% and 7.5%, respectively). In controls, the MAF was either similar for the c.1601G > A HABP2 variant (2.94%, ns) or significantly lower for the c.364C > T variant (0.73%, p = 0.016). The Arg122 residue lies in the EGF-3 domain of HABP2 which is important for its activation but, however, superposition of the predicted 3D structures of the wild type and mutated proteins suggests that this variant is tolerated at the protein level. In conclusion, our data do not support the pathogenicity of the HABP2 c.1601G > A variant but highlight the existence of a new one that should be more extensively searched for in fPTC patients and its pathogenicity more carefully evaluated.

Yu H, Jiang HL, Xu D, et al.
Transcription Factor MafB Promotes Hepatocellular Carcinoma Cell Proliferation through Up-Regulation of Cyclin D1.
Cell Physiol Biochem. 2016; 39(2):700-8 [PubMed] Related Publications
BACKGROUND/AIMS: MafB, a member of the Maf transcription factor family, plays a key role in the regulation of pancreatic alpha and beta cell differentiation. However, its function in the control of cancer cell proliferation remains unknown.
METHODS: The mRNA and protein expression levels of MafB in hepatocellular carcinoma tissues and adjacent non-tumor normal specimens were determined by real-time RT-PCR and Western blot, respectively. Report assay was performed to determine whether the regulation of Cyclin D1 by MafB is at the transcriptional level. The binding of MafB to the Cyclin D1 promoter was determined by Chromatin Immunoprecipitation (ChIP) assays. To determine the potential oncogenic effects of MafB in vivo, HepG2 cells transfected with adenovirus containing empty vector or MafB were injected subcutaneously to the skin under the front legs of the nude mice.
RESULTS: In the current study, we showed that MafB was markedly up-regulated in hepatocellular carcinoma (HCC) tissues and cells. Enforced overexpression of MafB enhanced, while its deficiency inhibited HCC cell proliferation. Mechanistically, Cyclin D1, an important regulator of cell cycle progression, was identified as a direct transcriptional target of MafB. Consistently, knockdown of Cyclin D1 largely attenuated the proliferative roles of MafB in HCC cells. Importantly, MafB overexpression significantly promoted cancer cell growth in mice.
CONCLUSIONS: Collectively, our results identified a novel HCC regulatory pathway involving MafB and Cyclin D1, the dysfunction of which drives proliferative character in HCC.

Davudian S, Mansoori B, Shajari N, et al.
BACH1, the master regulator gene: A novel candidate target for cancer therapy.
Gene. 2016; 588(1):30-7 [PubMed] Related Publications
BACH1 (BTB and CNC homology 1, basic leucine zipper transcription factor 1) is a transcriptional factor and a member of cap 'n' collar (CNC) and basic region leucine zipper factor family. In contrast to other bZIP family members, BACH1 appeared as a comparatively specific transcription factor. It acts as transcription regulator and is recognized as a recently hypoxia regulator and functions as an inducible repressor for the HO-1 gene in many human cell types in response to stress oxidative. In regard to studies lately, although, BACH1 has been related to the regulation of oxidative stress and heme oxidation, it has never been linked to invasion and metastasis. Recent studies have showed that BACH1 is involved in bone metastasis of breast cancer by up-regulating vital metastatic genes like CXCR4 and MMP1. This newly discovered aspect of BACH1 gene provides new insight into cancer progression study and stands on its master regulator role in metastasis process, raising the possibility of considering it as a potential target for cancer therapy.

Guisier F, Salaün M, Lachkar S, et al.
Molecular analysis of peripheral non-squamous non-small cell lung cancer sampled by radial EBUS.
Respirology. 2016; 21(4):718-26 [PubMed] Related Publications
BACKGROUND AND OBJECTIVE: Treatment optimization of non-squamous non-small-cell lung cancers (nonSq-NSCLC) relies on the molecular analysis of the tumour. We aimed to assess the predictive factors of molecular analysis feasibility (MAF) from samples of peripheral nonSq-NSCLC obtained by radial endobronchial ultrasound bronchoscopy (r-EBUS) and 1.5 mm microbiopsy forceps.
METHODS: We reviewed data from consecutive peripheral lung nodules sampled with r-EBUS between January 2012 and July 2014 at a single French University Hospital. nonSq-NSCLC were systematically analysed for EGFR, KRAS, ALK, HER2, PI3K and BRAF throughout the study, and c-MET and ROS1 alterations for the last 10 months.
RESULTS: Of 111 nonSq-NSCLC diagnosed by r-EBUS (113 procedures, mean nodule diameter 28 ± 15 mm), 88 were analysed for EGFR and ALK, 87 for KRAS, 86 for HER2, PI3K and BRAF and 14 for c-MET. Forty-one mutations were identified (23 KRAS, 10 EGFR, 2 BRAF, 1 HER2 and 5 ALK rearrangements). Four c-MET overexpressions were noted. MAF rose from 67% for the first 57 procedures to 89% for the last 56 procedures (P = 0.02) likely due to a higher number of biopsies performed (2 ± 1 vs 3 ± 2, P = 0.005). Upper or middle lobe location (OR 1.19, 95% CI: 1.02-1.38, P = 0.03), and at least three biopsies (OR 1.20, 95% CI: 1.04-1.40, P = 0.02) were predictive factors of MAF. Percentage of tumour cells, size of lesion and distance to the pleura did not correlate with MAF.
CONCLUSION: Multi-gene molecular analysis could be performed in nearly 80% of paraffin-embedded biopsies or smear specimens sampled by r-EBUS assisted bronchoscopy of peripheral tumoral lung nodules.

Fang M, Hutchinson L, Deng A, Green MR
Common BRAF(V600E)-directed pathway mediates widespread epigenetic silencing in colorectal cancer and melanoma.
Proc Natl Acad Sci U S A. 2016; 113(5):1250-5 [PubMed] Free Access to Full Article Related Publications
During cancer development, it is well established that many genes, including tumor suppressor genes, are hypermethylated and transcriptionally repressed, a phenomenon referred to as epigenetic silencing. In general, the factors involved in, and the mechanistic basis of, epigenetic silencing during cancer development are not well understood. We have recently described an epigenetic silencing pathway, directed by the oncogenic B-Raf proto-oncogene (BRAF) variant BRAF(V600E), that mediates widespread epigenetic silencing in colorectal cancer (CRC). Notably, the BRAF(V600E) mutation is also present in 50-70% of melanomas. Here, we show that the same pathway we identified in CRC also directs epigenetic silencing of a similar set of genes in BRAF-positive melanoma. In both CRC and melanoma, BRAF(V600E) promotes epigenetic silencing through up-regulation of v-maf avian musculoaponeurotic fibrosarcoma oncogene homolog G (MAFG), a transcriptional repressor with sequence-specific DNA-binding activity. The elevated concentration of MAFG drives DNA binding on the promoter. Promoter-bound MAFG recruits a set of corepressors that includes its heterodimeric partner BTB and CNC homology 1, basic leucine zipper transcription factor 1 (BACH1), the chromatin remodeling factor chromodomain helicase DNA-binding protein 8 (CHD8), and the DNA methyltransferase DNMT3B, resulting in hypermethylation and transcriptional silencing. Our results reveal a common BRAF(V600E)-directed transcriptional regulatory pathway that mediates epigenetic silencing in unrelated solid tumors and provide strong support for an instructive model of oncoprotein-directed epigenetic silencing.

Liu Y, Kheradmand F, Davis CF, et al.
Focused Analysis of Exome Sequencing Data for Rare Germline Mutations in Familial and Sporadic Lung Cancer.
J Thorac Oncol. 2016; 11(1):52-61 [PubMed] Free Access to Full Article Related Publications
INTRODUCTION: The association between smoking-induced chronic obstructive pulmonary disease (COPD) and lung cancer (LC) is well documented. Recent genome-wide association studies (GWAS) have identified 28 susceptibility loci for LC, 10 for COPD, 32 for smoking behavior, and 63 for pulmonary function, totaling 107 nonoverlapping loci. Given that common variants have been found to be associated with LC in genome-wide association studies, exome sequencing of these high-priority regions has great potential to identify novel rare causal variants.
METHODS: To search for disease-causing rare germline mutations, we used a variation of the extreme phenotype approach to select 48 patients with sporadic LC who reported histories of heavy smoking-37 of whom also exhibited carefully documented severe COPD (in whom smoking is considered the overwhelming determinant)-and 54 unique familial LC cases from families with at least three first-degree relatives with LC (who are likely enriched for genomic effects).
RESULTS: By focusing on exome profiles of the 107 target loci, we identified two key rare mutations. A heterozygous p.Arg696Cys variant in the coiled-coil domain containing 147 (CCDC147) gene at 10q25.1 was identified in one sporadic and two familial cases. The minor allele frequency (MAF) of this variant in the 1000 Genomes database is 0.0026. The p.Val26Met variant in the dopamine β-hydroxylase (DBH) gene at 9q34.2 was identified in two sporadic cases; the minor allele frequency of this mutation is 0.0034 according to the 1000 Genomes database. We also observed three suggestive rare mutations on 15q25.1: iron-responsive element binding protein neuronal 2 (IREB2); cholinergic receptor, nicotinic, alpha 5 (neuronal) (CHRNA5); and cholinergic receptor, nicotinic, beta 4 (CHRNB4).
CONCLUSIONS: Our results demonstrated highly disruptive risk-conferring CCDC147 and DBH mutations.

Garziera M, Catamo E, Crovella S, et al.
Association of the HLA-G 3'UTR polymorphisms with colorectal cancer in Italy: a first insight.
Int J Immunogenet. 2016; 43(1):32-9 [PubMed] Related Publications
This study aimed to explore functional and regulatory polymorphisms and haplotypes at the HLA-G 3'UTR region in colorectal cancer development. The presence of nonpolymorphic variants was also evaluated. Three-hundred and eight patients with colorectal cancer and 294 healthy controls were analysed at the germinal level. We found an association with increased risk of colorectal cancer for +2960 14-bp INDEL, +3196 C>G SNPs and UTR-2 haplotype, and a 'protective' role for +3003 T>C, +3010 C>G polymorphisms and UTR-4 haplotype. We detected in 3 distinct patients, a novel nucleotide change (+3037 C>A) and 2 already described rare variants, +3032 G/C (EUR MAF = 0.1%) and +3092 G/T (EUR MAF = 0%). This is the first study showing associations between different polymorphisms in the HLA-G 3'UTR and colorectal cancer susceptibility.

Ohguchi H, Hideshima T, Bhasin MK, et al.
The KDM3A-KLF2-IRF4 axis maintains myeloma cell survival.
Nat Commun. 2016; 7:10258 [PubMed] Related Publications
KDM3A is implicated in tumorigenesis; however, its biological role in multiple myeloma (MM) has not been elucidated. Here we identify KDM3A-KLF2-IRF4 axis dependence in MM. Knockdown of KDM3A is toxic to MM cells in vitro and in vivo. KDM3A maintains expression of KLF2 and IRF4 through H3K9 demethylation, and knockdown of KLF2 triggers apoptosis. Moreover, KLF2 directly activates IRF4 and IRF4 reciprocally upregulates KLF2, forming a positive autoregulatory circuit. The interaction of MM cells with bone marrow milieu mediates survival of MM cells. Importantly, silencing of KDM3A, KLF2 or IRF4 both decreases MM cell adhesion to bone marrow stromal cells and reduces MM cell homing to the bone marrow, in association with decreased ITGB7 expression in MAF-translocated MM cell lines. Our results indicate that the KDM3A-KLF2-IRF4 pathway plays an essential role in MM cell survival and homing to the bone marrow, and therefore represents a therapeutic target.

Janiszewska J, Szaumkessel M, Kostrzewska-Poczekaj M, et al.
Global miRNA Expression Profiling Identifies miR-1290 as Novel Potential oncomiR in Laryngeal Carcinoma.
PLoS One. 2015; 10(12):e0144924 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Laryngeal squamous cell carcinoma (LSCC) is the most common group among head and neck cancers. LSCC is characterized by a high incidence in Europe. With the aim of better understanding its genetic background we performed global miRNA expression profiling of LSCC cell lines and primary specimens. By this approach we identified a cohort of 33 upregulated and 9 downregulated miRNA genes in LSCC as compared to epithelial no tumor controls.
RESULTS: Within this group we identified overexpression of the novel miR-1290 gene not reported in the context of LSCC before. Using a combined bioinformatical approach in connection with functional analysis we delineated two putative target genes of miR-1290 namely ITPR2 and MAF which are significantly downregulated in LSCC. They are interesting candidates for tumor suppressor genes as they are implicated in apoptosis and other processes deregulated in cancer.
CONCLUSION: Taken together, we propose miR-1290 as the new oncomiR involved in LSCC pathogenesis. Additionally, we suggest that the oncogenic potential of miR-1290 might be expressed by the involvement in downregulation of its target genes MAF and ITPR2.

Xue H, Zhao H, Liu X, et al.
Association of single-nucleotide polymorphisms rs2197076 and rs2241883 of FABP1 gene with polycystic ovary syndrome.
J Assist Reprod Genet. 2016; 33(1):75-83 [PubMed] Free Access to Full Article Related Publications
PURPOSE: The objective of this study was to evaluate the association between single-nucleotide polymorphisms (SNPs) rs2197076 and rs2241883 in fatty acid-binding protein 1 (FABP1) gene and polycystic ovary syndrome (PCOS).
METHODS: The two alleles rs2197076 and rs2241883 in FABP1 gene in 221 PCOS women and 198 normal women were amplified and sequenced. Allele frequency comparison was performed between the PCOS and control groups, and genotype-phenotype correlation analysis was performed using dominant and recessive models to assess the association of FABP1 and the main features of PCOS.
RESULTS: Allele frequency analyses showed a strong association of SNPs rs2197076 and rs2241883 of FABP1 gene with PCOS (P < 0.001). The additive, dominant, and recessive genotype model analyses further supported this association even after adjusting for age and body mass index (BMI). The minor allele frequency (MAF) of rs2241883 in obese PCOS women was less than that in obese control women. Further genotype-phenotype correlation analysis showed that SNP rs2197076 had a stronger association with the main features of PCOS than SNP rs2241883.
CONCLUSION: In the association of SNPs in FABP1 gene with PCOS, rs2197076 was more closely associated with its main features than rs2241883 and seemed to play a more important role in the pathogenesis of PCOS.

Mbekeani JN, Abdel Fattah M, Al Nounou RM, et al.
Chronic Myelogenous Leukemia Relapse Presenting With Central Nervous System Blast Crisis and Bilateral Optic Nerve Infiltration.
J Neuroophthalmol. 2016; 36(1):73-7 [PubMed] Related Publications
Bilateral, simultaneous optic nerve sheath infiltration as a manifestation of leukemia relapse is very rare. A 45-year-old woman with chronic myelogenous leukemia was successfully treated to cytogenetic bone marrow remission 1 year previously and maintained on imatinib. She developed total bilateral blindness with marked, bilateral optic disc edema and evidence of bilateral optic nerve infiltration on magnetic resonance imaging. Cerebrospinal fluid cytology confirmed central nervous system (CNS) blast crisis. She recovered visual acuity of 20/20 in the right eye, and 20/25 in the left eye with salvage systemic and intrathecal chemotherapy before radiation therapy. Our report underscores the importance of timely and aggressive intervention of blast crisis of the CNS and the need for CNS penetrating induction and maintenance therapy.

Mancuso N, Rohland N, Rand KA, et al.
The contribution of rare variation to prostate cancer heritability.
Nat Genet. 2016; 48(1):30-5 [PubMed] Related Publications
We report targeted sequencing of 63 known prostate cancer risk regions in a multi-ancestry study of 9,237 men and use the data to explore the contribution of low-frequency variation to disease risk. We show that SNPs with minor allele frequencies (MAFs) of 0.1-1% explain a substantial fraction of prostate cancer risk in men of African ancestry. We estimate that these SNPs account for 0.12 (standard error (s.e.) = 0.05) of variance in risk (∼42% of the variance contributed by SNPs with MAF of 0.1-50%). This contribution is much larger than the fraction of neutral variation due to SNPs in this class, implying that natural selection has driven down the frequency of many prostate cancer risk alleles; we estimate the coupling between selection and allelic effects at 0.48 (95% confidence interval [0.19, 0.78]) under the Eyre-Walker model. Our results indicate that rare variants make a disproportionate contribution to genetic risk for prostate cancer and suggest the possibility that rare variants may also have an outsize effect on other common traits.

Deschasaux M, Souberbielle JC, Latino-Martel P, et al.
A prospective study of plasma 25-hydroxyvitamin D concentration and prostate cancer risk.
Br J Nutr. 2016; 115(2):305-14 [PubMed] Related Publications
Mechanistic hypotheses suggest that vitamin D and the closely related parathyroid hormone (PTH) may be involved in prostate carcinogenesis. However, epidemiological evidence is lacking for PTH and inconsistent for vitamin D. Our objectives were to prospectively investigate the association between vitamin D status, vitamin D-related gene polymorphisms, PTH and prostate cancer risk. A total of 129 cases diagnosed within the Supplémentation en Vitamines et Minéraux Antioxydants cohort were included in a nested case-control study and matched to 167 controls (13 years of follow-up). 25-Hydroxyvitamin D (25(OH)D) and PTH concentrations were assessed from baseline plasma samples. Conditional logistic regression models were computed. Higher 25(OH)D concentration was associated with decreased risk of prostate cancer (ORQ4 v. Q1 0·30; 95 % CI 0·12, 0·77; P trend=0·007). PTH concentration was not associated with prostate cancer risk (P trend=0·4) neither did the studied vitamin D-related gene polymorphisms. In this prospective study, prostate cancer risk was inversely associated with 25(OH)D concentration but not with PTH concentration. These results bring a new contribution to the understanding of the relationship between vitamin D and prostate cancer, which deserves further investigation.

Weinhold N, Heuck CJ, Rosenthal A, et al.
Clinical value of molecular subtyping multiple myeloma using gene expression profiling.
Leukemia. 2016; 30(2):423-30 [PubMed] Free Access to Full Article Related Publications
Using a data set of 1217 patients with multiple myeloma enrolled in Total Therapies, we have examined the impact of novel therapies on molecular and risk subgroups and the clinical value of molecular classification. Bortezomib significantly improved the progression-free survival (PFS) and overall survival (OS) of the MMSET (MS) subgroup. Thalidomide and bortezomib positively impacted the PFS of low-risk (LoR) cases defined by the GEP70 signature, whereas high-risk (HiR) cases showed no significant changes in outcome. We show that molecular classification is important if response rates are to be used to predict outcomes. The t(11;14)-containing CD-1 and CD-2 subgroups showed clear differences in time to response and cumulative response rates but similar PFS and OS. Furthermore, complete remission was not significantly associated with the outcome of the MAF/MAFB (MF) subgroup or HiR cases. HiR cases were enriched in the MF, MS and proliferation subgroups, but the poor outcome of these groups was not linked to subgroup-specific characteristics such as MAF overexpression per se. It is especially important to define risk status if HiR cases are to be managed appropriately because of their aggressive clinical course, high rates of early relapse and the need to maintain therapeutic pressure on the clone.

Krivokuca A, Yanowski K, Rakobradovic J, et al.
RAD51C mutation screening in high-risk patients from Serbian hereditary breast/ovarian cancer families.
Cancer Biomark. 2015; 15(6):775-81 [PubMed] Related Publications
BACKGROUND: In 2010 an important finding was published showing that heterozygous mutations in RAD51C were highly penetrant and were able to confer an increased risk for breast and ovarian cancers. The role of possible third high penetrance breast cancer susceptibility gene was assigned to RAD51C.
OBJECTIVE: Because of its rising importance in breast cancer development and the lack of information about RAD51C in Slavic populations, our goal was to identify potential population specific mutations in this gene in order to determine more detailed genetic screening strategy and breast cancer risk assessment.
METHODS: The study included 55 females from Serbian hereditary breast/ovarian cancer families negative for sequence alterations and large genomic rearrangements in BRCA1/2 genes. Whole coding region and exon-intron boundaries of RAD51C were analyzed by dHPLC. All mutations were confirmed by Sanger sequencing. SIFT and Polyphen were used to predict possible impact of non-synonymous variants.
RESULTS: We found 5 variants in RAD51C including two missense, one intronic, one in the 5'UTR and one variant in the promoter region of the gene. Three detected variants are common - c.1-118G>A (rs16943176, MAF = 0,203); c.1-26C>T (rs12946397, MAF = 0,207) and c.904+34T>C (rs28363318, MAF = 0,186). We detected two missense variants, c.790G>A (p.Gly264Ser) in exon 5 and c.859A>G (p.Thr287Ala) in exon 6. Both of them were previously shown to exhibit reduced protein function but their contribution to cancer risk is still unknown.
CONCLUSIONS: Although the initial reports implied that RAD51C might be promising candidate for next high penetrance breast cancer susceptibility gene, lack of confirmation suggested that RAD51C mutations are not as common as expected. Our study did not reveal truncating mutations in RAD51C suggesting that other breast cancer susceptibility genes may account for the increased susceptibility in our cohort of high-risk BRCA1/2 negative families.

Lemire M, Qu C, Loo LW, et al.
A genome-wide association study for colorectal cancer identifies a risk locus in 14q23.1.
Hum Genet. 2015; 134(11-12):1249-62 [PubMed] Free Access to Full Article Related Publications
Over 50 loci associated with colorectal cancer (CRC) have been uncovered by genome-wide association studies (GWAS). Identifying additional loci has the potential to help elucidate aspects of the underlying biological processes leading to better understanding of the pathogenesis of the disease. We re-evaluated a GWAS by excluding controls that have family history of CRC or personal history of colorectal polyps, as we hypothesized that their inclusion reduces power to detect associations. This is supported empirically and through simulations. Two-phase GWAS analysis was performed in a total of 16,517 cases and 14,487 controls. We identified rs17094983, a SNP associated with risk of CRC [p = 2.5 × 10(-10); odds ratio estimated by re-including all controls (OR) = 0.87, 95% confidence interval (CI) 0.83-0.91; minor allele frequency (MAF) = 13%]. Results were replicated in samples of African descent (1894 cases and 4703 controls; p = 0.01; OR = 0.86, 95% CI 0.77-0.97; MAF = 16 %). Gene expression data in 195 colon adenocarcinomas and 59 normal colon tissues from two different studies revealed that this locus has genotypes that are associated with RTN1 (Reticulon 1) expression (p = 0.001), a protein-coding gene involved in survival and proliferation of cancer cells which is highly expressed in normal colon tissues but has significantly reduced expression in tumor cells (p = 1.3 × 10(-8)).

Pavlovic M, Arnal-Estapé A, Rojo F, et al.
Enhanced MAF Oncogene Expression and Breast Cancer Bone Metastasis.
J Natl Cancer Inst. 2015; 107(12):djv256 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: There are currently no biomarkers for early breast cancer patient populations at risk of bone metastasis. Identification of mediators of bone metastasis could be of clinical interest.
METHODS: A de novo unbiased screening approach based on selection of highly bone metastatic breast cancer cells in vivo was used to determine copy number aberrations (CNAs) associated with bone metastasis. The CNAs associated with bone metastasis were examined in independent primary breast cancer datasets with annotated clinical follow-up. The MAF gene encoded within the CNA associated with bone metastasis was subjected to gain and loss of function validation in breast cancer cells (MCF7, T47D, ZR-75, and 4T1), its downstream mechanism validated, and tested in clinical samples. A multivariable Cox cause-specific hazard model with competing events (death) was used to test the association between 16q23 or MAF and bone metastasis. All statistical tests were two-sided.
RESULTS: 16q23 gain CNA encoding the transcription factor MAF mediates breast cancer bone metastasis through the control of PTHrP. 16q23 gain (hazard ratio (HR) for bone metastasis = 14.5, 95% confidence interval (CI) = 6.4 to 32.9, P < .001) as well as MAF overexpression (HR for bone metastasis = 2.5, 95% CI = 1.7 to 3.8, P < .001) in primary breast tumors were specifically associated with risk of metastasis to bone but not to other organs.
CONCLUSIONS: These results suggest that MAF is a mediator of breast cancer bone metastasis. 16q23 gain or MAF protein overexpression in tumors may help to select patients at risk of bone relapse.

Kervoëlen C, Ménoret E, Gomez-Bougie P, et al.
Dexamethasone-induced cell death is restricted to specific molecular subgroups of multiple myeloma.
Oncotarget. 2015; 6(29):26922-34 [PubMed] Free Access to Full Article Related Publications
Due to its cytotoxic effect in lymphoid cells, dexamethasone is widely used in the treatment of multiple myeloma (MM). However, only a subset of myeloma patients responds to high-dose dexamethasone. Despite the undeniable anti-myeloma benefits of dexamethasone, significant adverse effects have been reported. We re-evaluate the anti-tumor effect of dexamethasone according to the molecular heterogeneity of MM. We demonstrated that the pro-death effect of dexamethasone is related to the genetic heterogeneity of MM because sensitive cell lines were restricted to MAF and MMSET signature subgroups, whereas all CCND1 cell lines (n = 10) were resistant to dexamethasone. We demonstrated that the glucocorticoid receptor expression was an important limiting factor for dexamethasone-induced cell death and we found a correlation between glucocorticoid receptor levels and the induction of glucocorticoid-induced leucine zipper (GILZ) under dexamethasone treatment. By silencing GILZ, we next demonstrated that GILZ is necessary for Dex induced apoptosis while triggering an imbalance between anti- and pro-apoptotic Bcl-2 proteins. Finally, the heterogeneity of the dexamethasone response was further confirmed in vivo using myeloma xenograft models. Our findings suggested that the effect of dexamethasone should be re-evaluated within molecular subgroups of myeloma patients to improve its efficacy and reduce its adverse effects.

Kinnersley B, Kamatani Y, Labussière M, et al.
Search for new loci and low-frequency variants influencing glioma risk by exome-array analysis.
Eur J Hum Genet. 2016; 24(5):717-24 [PubMed] Free Access to Full Article Related Publications
To identify protein-altering variants (PAVs) for glioma, we analysed Illumina HumanExome BeadChip exome-array data on 1882 glioma cases and 8079 controls from three independent European populations. In addition to single-variant tests we incorporated information on the predicted functional consequences of PAVs and analysed sets of genes with a higher likelihood of having a role in glioma on the basis of the profile of somatic mutations documented by large-scale sequencing initiatives. Globally there was a strong relationship between effect size and PAVs predicted to be damaging (P=2.29 × 10(-49)); however, these variants which are most likely to impact on risk, are rare (MAF<5%). Although no single variant showed an association which was statistically significant at the genome-wide threshold a number represented promising associations - BRCA2:c.9976A>T, p.(Lys3326Ter), which has been shown to influence breast and lung cancer risk (odds ratio (OR)=2.3, P=4.00 × 10(-4) for glioblastoma (GBM)) and IDH2:c.782G>A, p.(Arg261His) (OR=3.21, P=7.67 × 10(-3), for non-GBM). Additionally, gene burden tests revealed a statistically significant association for HARS2 and risk of GBM (P=2.20 × 10(-6)). Genome scans of low-frequency PAVs represent a complementary strategy to identify disease-causing variants compared with scans based on tagSNPs. Strategies to lessen the multiple testing burden by restricting analysis to PAVs with higher priors affords an opportunity to maximise study power.

Sumiya Y, Ishikawa M, Inoue T, et al.
Macrophage Activation Mechanisms in Human Monocytic Cell Line-derived Macrophages.
Anticancer Res. 2015; 35(8):4447-51 [PubMed] Related Publications
BACKGROUND: Although the mechanisms of macrophage activation are important for cancer immunotherapy, they are poorly understood. Recently, easy and robust assay systems for assessing the macrophage-activating factor (MAF) using monocytic cell line-derived macrophages were established.
MATERIALS AND METHODS: Gene-expression profiles of U937- and THP-1-derived macrophages were compared using gene expression microarray analysis and their responses against several MAFs were examined by in vitro experiments.
RESULTS: Activated states of these macrophages could not be assigned to a specific sub-type but showed, however, different unique characteristics.
CONCLUSION: The unique of monocytic cell line-derived macrophages could provide clues to understand the activation mechanism of macrophages and, therefore, help to develop effective cancer immunotherapy with MAFs.

Bystrom J, Taher TE, Muhyaddin MS, et al.
Harnessing the Therapeutic Potential of Th17 Cells.
Mediators Inflamm. 2015; 2015:205156 [PubMed] Free Access to Full Article Related Publications
Th17 cells provide protective immunity to infections by fungi and extracellular bacteria as well as cancer but are also involved in chronic inflammation. The cells were first identified by their ability to produce interleukin 17A (IL-17A) and, subsequently, associated with chronic inflammation and autoimmunity. Th17 cells have some gene profile similarity with stem cells and can remain dormant in mucosal tissues for long periods. Indeed, recent studies suggest that functionally distinct subsets of pro- and anti-inflammatory Th17 cells can interchange phenotype and functions. For development, Th17 cells require activation of the transcription factors STAT3 and RORγt while RUNX1, c-Maf, and Aiolos are involved in changes of phenotype/functions. Attempts to harness Th17 cells against pathogens and cancer using vaccination strategies are being explored. The cells gain protective abilities when induced to produce interferon γ (IFNγ). In addition, treatment with antibodies to IL-17 is effective in treating patients with psoriasis, psoriatic arthritis, and refectory rheumatoid arthritis. Moreover, since RORγt is a nuclear receptor, it is likely to be a potential future drug target for modulating Th17 functions. This review explores pathways through which Th17 subsets are induced, the molecular basis of their plasticity, and potential therapeutic strategies for their modulation in diseases.

Helgason H, Rafnar T, Olafsdottir HS, et al.
Loss-of-function variants in ATM confer risk of gastric cancer.
Nat Genet. 2015; 47(8):906-10 [PubMed] Related Publications
Gastric cancer is a serious health problem worldwide, with particularly high prevalence in eastern Asia. Genome-wide association studies (GWAS) in Asian populations have identified several loci that associate with gastric cancer risk. Here we report a GWAS of gastric cancer in a European population, using information on 2,500 population-based gastric cancer cases and 205,652 controls. We found a new gastric cancer association with loss-of-function mutations in ATM (gene test, P = 8.0 × 10(-12); odds ratio (OR) = 4.74). The combination of the loss-of-function variants p.Gln852*, p.Ser644* and p.Tyr103* (combined minor allele frequency (MAF) = 0.3%) also associates with pancreatic and prostate cancers (OR = 3.81 and 2.18, respectively) and gives an indication of risk of breast and colorectal cancers (OR = 1.82 and 1.97, respectively). Cancers in those carrying loss-of-function ATM mutations are diagnosed at a significantly earlier age than in non-carriers. Our results confirm an association between gastric cancer in Europeans and three loci previously reported in Asians, MUC1, PRKAA1 and PSCA, refine the association signal at PRKAA1 and support a pathogenic role for the tandem repeat identified in MUC1.

Yang W, Lan X, Li D, et al.
MiR-223 targeting MAFB suppresses proliferation and migration of nasopharyngeal carcinoma cells.
BMC Cancer. 2015; 15:461 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Mounting evidence suggests that miRNAs have major functions in tumor pathogenesis, and this study aimed to identify the candidate miRNA and investigate its role in nasopharyngeal carcinoma (NPC).
METHODS: MiRNA and mRNA expressions were screened by microarray assays. The cell proliferation, colony formation and migration ability were measured by MTT, soft agar and wound healing assays, respectively. The tumor growth suppression was evaluated by xenografting in nude mice. The plasma miR-223 levels in NPC patients were detected by TaqMan analysis. Real-time quantitative PCR and Western blotting were used to confirm miR-223 and MAFB expression levels. The targeting relationship between miR-223 and MAFB was verified using dual luciferase reporter assay.
RESULTS: The miR-223 expression was decreased in CNE-1, CNE-2 cells as compared with NP69 cells, an immortalized human nasopharyngeal epithelial cell line, and its level also reduced in NPC patients' plasma as compared with healthy controls. Exogenous expression of miR-223 in CNE-2 cells could inhibit cell proliferation both in vitro and in vivo. Extrogenous miR-223 in CNE-2 cells would decrease the ability of colony formation and migration. MAFB, a transcription factor of Maf family members, was identified as a target gene of miR-223. We found that migration and invasion abilities were inhibited by MAFB silencing.
CONCLUSIONS: MiR-223 negatively regulates the growth and migration of NPC cells via reducing MAFB expression, and this finding provides a novel insight into understanding miR-223 regulation mechanism in nasopharyngeal carcinoma tumorigenesis.

Juárez Salcedo LM, López Rubio M, Gil Fernández JJ, et al.
Atypical IgM multiple myeloma with deletion of c-MAF.
Int J Lab Hematol. 2015; 37(5):686-9 [PubMed] Related Publications
IgM multiple myeloma (MM) is a rare subtype of myeloma that shares clinical and pathological features with Waldenström's macroglobulinaemia. These are two separate entities that differ both in therapy and prognosis. We report a 57-year-old male, who presented with anaemia, hypercalcaemia, acute renal failure and several vertebral fractures that clinically suggested a multiple myeloma. Further investigations revealed a serum monoclonal component of IgM lambda type and a bone marrow infiltrated by small, lymphoplasmocytic cells. IgM MM was finally diagnosed by means of both inmunophenotypic and immunohistochemistry techniques, stressing the importance of inmunophenotypic evaluation when clinical and morphological features are discordant. Fluorescence in situ hybridization (FISH) studies disclosed a particular combination of deletion 13q14, t(11;14) and monoallelic deletion C-MAF without t(14;16). The clinical evolution after a Bortezomib-containing polychemotherapy and autologous stem cell transplantation (ASCT) conditioned with busulphan and melphalan is also presented. This very uncommon case highlights the impact of immunophenotyping on the differential diagnosis between IgM MM and WM, to choose the best treatment and establish an appropriate outcome.

Al-Tassan NA, Whiffin N, Hosking FJ, et al.
A new GWAS and meta-analysis with 1000Genomes imputation identifies novel risk variants for colorectal cancer.
Sci Rep. 2015; 5:10442 [PubMed] Free Access to Full Article Related Publications
Genome-wide association studies (GWAS) of colorectal cancer (CRC) have identified 23 susceptibility loci thus far. Analyses of previously conducted GWAS indicate additional risk loci are yet to be discovered. To identify novel CRC susceptibility loci, we conducted a new GWAS and performed a meta-analysis with five published GWAS (totalling 7,577 cases and 9,979 controls of European ancestry), imputing genotypes utilising the 1000 Genomes Project. The combined analysis identified new, significant associations with CRC at 1p36.2 marked by rs72647484 (minor allele frequency [MAF] = 0.09) near CDC42 and WNT4 (P = 1.21 × 10(-8), odds ratio [OR] = 1.21 ) and at 16q24.1 marked by rs16941835 (MAF = 0.21, P = 5.06 × 10(-8); OR = 1.15) within the long non-coding RNA (lncRNA) RP11-58A18.1 and ~500 kb from the nearest coding gene FOXL1. Additionally we identified a promising association at 10p13 with rs10904849 intronic to CUBN (MAF = 0.32, P = 7.01 × 10(-8); OR = 1.14). These findings provide further insights into the genetic and biological basis of inherited genetic susceptibility to CRC. Additionally, our analysis further demonstrates that imputation can be used to exploit GWAS data to identify novel disease-causing variants.

Min XS, Huang P, Liu X, et al.
Bioinformatics analyses of significant prognostic risk markers for thyroid papillary carcinoma.
Tumour Biol. 2015; 36(10):7457-63 [PubMed] Related Publications
This study was aimed to identify the prognostic risk markers for thyroid papillary carcinoma (TPC) by bioinformatics. The clinical data of TPC and their microRNAs (miRNAs) and genes expression profile data were downloaded from The Cancer Genome Atlas. Elastic net-Cox's proportional regression hazards model (EN-COX) was used to identify the prognostic associated factors. The receiver operating characteristic (ROC) curve and Kaplan-Meier (KM) curve were used to screen the significant prognostic risk miRNA and genes. Then, the target genes of the obtained miRNAs were predicted followed by function prediction. Finally, the significant risk genes were performed literature mining and function analysis. Total 1046 miRNAs and 20531 genes in 484 cases samples were identified after data preprocessing. From the EN-COX model, 30 prognostic risk factors were obtained. Based on the 30 risk factors, 3 miRNAs and 11 genes were identified from the ROC and KM curves. The target genes of miRNA-342 such as B-cell CLL/lymphoma 2 (BCL2) were mainly enriched in the biological process related to cellular metabolic process and Disease Ontology terms of lymphoma. The target genes of miRNA-93 were mainly enriched in the pathway of G1 phase. Among the 11 prognostic risk genes, v-maf avian musculoaponeurotic fibrosarcoma oncogene homologue F (MAFF), SRY (sex-determining region Y)-box 4 (SOX4), and retinoic acid receptor, alpha (RARA) encoded transcription factors. Besides, RARA was enriched in four pathways. These prognostic markers such as miRNA-93, miRNA-342, RARA, MAFF, SOX4, and BCL2 may be used as targets for TPC chemoprevention.

Walker BA, Wardell CP, Murison A, et al.
APOBEC family mutational signatures are associated with poor prognosis translocations in multiple myeloma.
Nat Commun. 2015; 6:6997 [PubMed] Free Access to Full Article Related Publications
We have sequenced 463 presenting cases of myeloma entered into the UK Myeloma XI study using whole exome sequencing. Here we identify mutations induced as a consequence of misdirected AID in the partner oncogenes of IGH translocations, which are activating and associated with impaired clinical outcome. An APOBEC mutational signature is seen in 3.8% of cases and is linked to the translocation-mediated deregulation of MAF and MAFB, a known poor prognostic factor. Patients with this signature have an increased mutational load and a poor prognosis. Loss of MAF or MAFB expression results in decreased APOBEC3B and APOBEC4 expression, indicating a transcriptional control mechanism. Kataegis, a further mutational pattern associated with APOBEC deregulation, is seen at the sites of the MYC translocation. The APOBEC mutational signature seen in myeloma is, therefore, associated with poor prognosis primary and secondary translocations and the molecular mechanisms involved in generating them.

Wang S, Lv C, Jin H, et al.
A common genetic variation in the promoter of miR-107 is associated with gastric adenocarcinoma susceptibility and survival.
Mutat Res. 2014; 769:35-41 [PubMed] Related Publications
BACKGROUND: Global miRNA expression profile has been widely used to characterize human cancers. It is well established that genetic variants in miRNAs can modulate miRNA biogenesis and disease risk.
METHODS: Genome-wide miRNA microarray was employed for assessment of miRNA expression profile of gastric adenocarcinoma (GAC). The variants of significantly dysregulated miRNA were genotyped in test (715 cases and 804 controls) and validation (940 cases and 1050 controls) subject sets.
RESULTS: MiRNA microarray revealed that 12 miRNAs including miR-107 significantly dysregulated in GAC tissues. The sequencing of the promoter of miR-107 identified 3 SNPs (rs11185777, rs78591545, and rs2296616) with minor allele frequency (MAF)>5%. Analyzing their association with GAC risk and prognosis revealed that the C allele of rs2296616 (T>C) was significantly associated with the decreased risk of GAC among the test, validation and combined sets (TC/CC vs. TT, adjusted OR=0.39, 95% CI=0.31-0.49 for the combined set). However, the C allele was related to an unfavorable prognosis of Cardia GAC (CGAC) (adjusted HR=1.49, 95% CI=1.01-2.20). In vivo evidence showed that the individuals with the rs2296616C allele had lower miR-107 expression compared with the homozygous T allele carriers.
CONCLUSION: miR-107 is dysregulated in GAC pathogenesis and the SNP rs2296616 may play a role in the process.

Sarkar D, Leung EY, Baguley BC, et al.
Epigenetic regulation in human melanoma: past and future.
Epigenetics. 2015; 10(2):103-21 [PubMed] Free Access to Full Article Related Publications
The development and progression of melanoma have been attributed to independent or combined genetic and epigenetic events. There has been remarkable progress in understanding melanoma pathogenesis in terms of genetic alterations. However, recent studies have revealed a complex involvement of epigenetic mechanisms in the regulation of gene expression, including methylation, chromatin modification and remodeling, and the diverse activities of non-coding RNAs. The roles of gene methylation and miRNAs have been relatively well studied in melanoma, but other studies have shown that changes in chromatin status and in the differential expression of long non-coding RNAs can lead to altered regulation of key genes. Taken together, they affect the functioning of signaling pathways that influence each other, intersect, and form networks in which local perturbations disturb the activity of the whole system. Here, we focus on how epigenetic events intertwine with these pathways and contribute to the molecular pathogenesis of melanoma.

Zidi S, Stayoussef M, Gazouani E, et al.
Relationship of common vascular endothelial growth factor polymorphisms and haplotypes with the risk of cervical cancer in Tunisians.
Cytokine. 2015; 74(1):108-12 [PubMed] Related Publications
OBJECTIVE: We investigated the association between common vascular endothelial growth factor (VEGF) single nucleotide polymorphisms (SNPs) and the risk of cervical cancer (CC) in Tunisian patients and control women.
METHODS: Study subjects comprised 86 CC cases and 124 control women. Genotyping of VEGF rs699947, rs833061, rs1570360, rs2010963, rs25648, rs833068, rs833070, rs3025039 SNPs was done by real-time PCR.
RESULTS: Higher minor allele frequencies (MAF) of rs699947 (-2578C/A) [P=0.04; OR (95% CI)=1.52 (1.02-2.29)], and rs1570360 (-1154G/A) [P=0.04; OR (95% CI)=1.58 (1.01-2.47)] were seen in CC cases compared to control women. Marked differences in the distribution of rs699947 (P=9×10(-4)) and rs1570360 (P=0.03) genotypes were seen between CC cases and control groups; the distribution of the remaining SNPs was comparable between CC cases and control women. The association of rs699947 and rs1570360 with heightened CC risk with was seen in the heterozygous, and more so in the homozygous states. Haploview analysis revealed high LD between rs699947, rs833061, rs1570360, rs2010963, rs25648, rs833068 and rs833070 but weak or no LD between rs3025039 and the other SNPs. Seven-locus (rs699947/rs833061/rs1570360/rs2010963/rs25648/rs833068/ rs833070) haploview analysis identified only CTGCCAG haplotype to be positively associated with CC [P=0.022; OR(95% CI)=1.74 (1.08-2.79)].
CONCLUSION: Specific VEGF variants (rs699947, rs1570360) and haplotype (CTGCCAG) may contribute to the development of CC among Tunisian women.

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