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Human Molecular Genetics Advance Access originally published online on March 1, 2006
Human Molecular Genetics 2006 15(8):1271-1277; doi:10.1093/hmg/ddl042
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© The Author 2006. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oxfordjournals.org

Down-regulation of the cytoglobin gene, located on 17q25, in tylosis with oesophageal cancer (TOC): evidence for trans-allele repression

Fiona E. McRonald1, Triantafillos Liloglou2, George Xinarianos2, Laura Hill1, Lynn Rowbottom1, Joanne E. Langan1, Anthony Ellis3, Joan M. Shaw3, John K. Field1,2 and Janet M. Risk1,*

1Molecular Genetics and Oncology Group, School of Dental Sciences, University of Liverpool, Edwards Building, Daulby Street, Liverpool L69 3GN, UK, 2University of Liverpool Cancer Research Centre, Liverpool L3 9TA, UK and 3Department of Gastroenterology, Royal Liverpool University Hospital, Liverpool L7 8XP, UK

* To whom correspondence should be addressed. Tel: +44 01517065265; Fax: +44 01517065809; Email: j.m.risk{at}liverpool.ac.uk

Received December 22, 2005; Revised February 17, 2006; Accepted February 24, 2006


   ABSTRACT
TOP
 ABSTRACT
INTRODUCTION
 RESULTS
 DISCUSSION
 MATERIALS AND METHODS
 REFERENCES
 
Tylosis (focal non-epidermolytic palmoplantar keratoderma) is an autosomal dominant skin disorder that is associated with the early onset of squamous cell oesophageal cancer (SCOC) in three families. Our previous linkage and haplotype analyses have mapped the tylosis with oesophageal cancer (TOC) locus to a 42.5 kb region on chromosome 17q25 that has also been implicated in the aetiology of sporadically occurring SCOC from a number of different geographical populations. Oesophageal cancer is one of the 10 leading causes of cancer mortality worldwide. No inherited disease-causing mutations have been identified in the genes located in the 42.5 kb minimal region. We now show that cytoglobin gene expression in oesophageal biopsies from tylotic patients is dramatically reduced by approximately 70% compared with normal oesophagus. Furthermore, both alleles are equally repressed. Given the autosomal dominant nature of the disease, these results exclude haploinsufficiency as a mechanism of the disease and instead suggest a novel trans-allele interaction. We also show that the promoter is hypermethylated in sporadic oesophageal cancer samples: this may constitute the ‘second hit’ of a gene previously implicated in this disease by allelic imbalance studies.


   INTRODUCTION
TOP
 ABSTRACT
 INTRODUCTION
RESULTS
 DISCUSSION
 MATERIALS AND METHODS
 REFERENCES
 
Type A tylosis (focal non-epidermolytic palmoplantar keratoderma) is associated with oral leukokeratosis, follicular keratosis and a high risk of squamous cell oesophageal cancer (SCOC) in three families (1Go–3Go). The syndrome, named tylosis with oesophageal cancer (TOC; OMIM 148500 [OMIM] ), is inherited as an autosomal dominant with complete penetrance of the skin phenotype between 5 years of age and puberty. TOC has been mapped to a 42.5 kb region on chromosome 17q25, eliminating the strong candidate gene, envoplakin (4Go–7Go). Allelic imbalance [AI; or loss of heterozygosity (LOH)] studies of this region of 17q25 implicate the TOC locus in sporadically occurring squamous cell oesophageal tumours (8Go–10Go). The identification and characterisation of this gene is, therefore, of importance because sporadic oesophageal cancer is a major cause of mortality in both developing and developed countries.

The 42.5 kb TOC minimal region contains the promoter of one gene (FLJ22341), the entire cytoglobin (CYGB) gene and the 5' end of an uncharacterised gene (‘FM8’/Unigene Hs.434271) that completely overlaps CYGB in the opposite orientation (7Go). This latter gene shows a high degree of alternative splicing, and may be a non-coding RNA, as it contains no significant open reading frame.

Sequencing of genomic DNA from affected and unaffected TOC family members has identified two putative disease-specific alterations, but these are located in regions of no known function, outside the known genes (7Go). Furthermore, no somatic mutations in the coding regions of CYGB have been observed in a series of 40 sporadic squamous cell oesophageal carcinomas (10Go). However, gene expression has not previously been investigated. In this article, we describe the results of expression analyses on the three genes located partially or wholly within the minimal region in tylotic and normal tissue, and discuss possible mechanisms to explain these results.


   RESULTS
TOP
 ABSTRACT
 INTRODUCTION
 RESULTS
DISCUSSION
 MATERIALS AND METHODS
 REFERENCES
 
Expression of the FLJ22341 and CYGB genes in oesophageal biopsies was studied in a semi-quantitative manner by relative multiplex RT–PCR, using fluorescently labelled primers for the above genes and TATA box binding protein (TBP). The relative expression of FLJ22341 in oesophageal tissue was observed to be similar in patients with tylosis, in normal controls and in the unaffected tissue of patients with gastro-oesophageal reflux disease (GORD). In contrast, CYGB gene expression in oesophageal biopsies from 18 individuals with tylosis was significantly lower than in 10 control biopsies from normal individuals (P=0.004), with relative expression being reduced by nearly 70% (relative expression, 0.34; 95% CI, 0.20–0.57). Furthermore, in the normal squamous oesophageal epithelium from seven patients with GORD, CYGB expression was significantly increased when compared with normal controls (P=0.0004; relative expression, 4.7; 95% CI, 2.1–10.4) (Fig. 1).


Figure 0421
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  		Figure 1. Examples of relative multiplex RT–PCR of oesophageal biopsy tissue using CYGB and TBP primers. (A) Agarose gel electrophoresis. (B) Representative ABI 3100 GeneScanner traces from normal (top), tylotic (middle) and GORD (bottom) oesophageal biopsies. Numbers below the peaks show PCR product size in base pairs (upper box) and the area under the curve (lower box).

 
In order to determine whether down-regulation of CYGB was allele-specific, as would be expected in an autosomal dominant disease, SSCP screening of genomic DNA from 21 individuals with tylosis and seven GORD patients was undertaken at the dinucleotide polymorphism rs4238995, which lies in the CYGB 3' UTR. Six heterozygotes (three individuals with tylosis, and three with GORD) were identified; in each case, heterozygosity was confirmed by sequencing of genomic DNA. An oesophageal RT–PCR product encompassing the polymorphism of interest was sequenced for each of these six patients. Retention of heterozygosity was observed in the cDNA in all six cases, indicating that both alleles of CYGB are expressed at apparently equal levels in individuals with tylosis and non-tylotic controls.

Although both copies of the CYGB gene were shown to be down-regulated, it was unclear whether this was because of repression at the transcriptional or post-transcriptional level. To investigate the possibility of an antisense transcript causing post-transcriptional down-regulation of both alleles of CYGB via RNA interference (RNAi), we studied expression of the FM8 gene, which overlaps CYGB in the opposite orientation. Expression of FM8 was observed in oesophageal biopsies, but no evidence for tylosis-specific expression differences was obtained. Examination of a SNP in exon 5 of FM8 showed equal expression of both alleles in oesophagus tissue from tylosis patients and controls, and multiplex RT–PCR of the commonly transcribed FM8 exons 2 and 3 with CYGB and TBP showed no evidence for expression differences in tylotic oesophageal tissue.

The alternative possibility, transcriptional down-regulation of CYGB was investigated by examining the methylation status of the CYGB promoter by bisulphite pyrosequencing. A low level of CYGB promoter methylation [methylation index (MtI) <10%] was observed for normal and tylotic oesophageal biopsy DNA and for normal and tylotic lymphocyte DNA (Table 1). DNA from normal tissue adjacent to sporadic oesophageal squamous cell cancer also demonstrated a low MtI, however tumour-derived DNA showed a significantly higher MtI (19%) than the paired normal tissue (7%) (Fig. 2, Table 1) (two-tailed paired t-test; P=0.02). This series of tumours demonstrated AI at microsatellite loci adjacent to, and within, the TOC minimal region. Furthermore, the expression of CYGB in five cell lines derived from sporadic squamous cell oesophageal carcinomas was very low or undetectable when compared with normal oesophageal biopsy tissue or a myofibroblast cell line, and this expression data correlated with the level of methylation observed at the CYGB gene promoter (Fig. 3).


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  		Table 1. Summary of methylation status of the CYGB promoter using bisulphite pyrosequencing
 

Figure 0422
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  		Figure 2. Bisulphite pyrosequencing of four CpG residues in the CYGB promoter. The four targeted cytosines are enclosed in squares and indicated by arrows (the reverse strand was read so that G peaks indicate methylated cytosine, whereas A indicates unmethylated cytosine). The control, non-CpG cytosine residue showing complete conversion of cytosine to uracil by bisulphite treatment is shown in the right hand box. Normal tissue (top) demonstrates no methylation, whereas tumour tissue (bottom) demonstrates a significant level of methylation at all four target bases. The MtI is calculated as the average rate of G incorporation at all CpGs.

 

Figure 0423
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  		Figure 3. CYGB expression levels and promoter methylation in cell lines. Lane 1: OE21; lane 2: KYSE-510; lane 3: KYSE-410; lane 4: KYSE-270; lane 5: KYSE-140; lane 6: CCD-18Co. (A) Relative, multiplex RT–PCR using CYGB (top) and TBP (bottom) primers. (B) Control RT–PCR using primers for ß-actin. (C) MtI for CYGB promoter.

 

   DISCUSSION
TOP
 ABSTRACT
 INTRODUCTION
 RESULTS
 DISCUSSION
MATERIALS AND METHODS
 REFERENCES
 
Previous research in our laboratories has been unable to identify a TOC-specific mutation in any part of the three genes partially or wholly located within the 42.5 kb TOC minimal region (7Go). However, our current data implicate down-regulation of CYGB as contributing to the TOC phenotype and, furthermore, indicate a possible role for CYGB in a proportion of sporadic OSCC. The data show no alterations in expression levels of other candidate genes located within the minimal region. The FLJ22341 gene (whose promoter is located within the TOC minimal region 25 kb from the 3' end of CYGB) would thus appear not to be implicated in TOC despite its recent identification as a strong candidate tumour suppressor gene in ovarian cancer (11Go) and its homology to the Drosophila Rhomboid-1 gene [a putative intra-membrane serine protease that facilitates signalling within the Spitz/EGFR/MAPK pathway; (12Go)]. The putative gene, FM8 (Unigene Hs.434271), is also excluded as a candidate with the proviso that subtle changes in its expression, or novel disease-specific splice variants, may yet be shown to control CYGB expression by RNAi. We also have expression data that shows no TOC-specific expression changes in SThM (located 28 kb from the 5' of CYGB) or envoplakin (a candidate gene previously investigated by mutation analysis and located 250 kb upstream of the TOC minimal region). This excludes the possibility of a localised transcriptional repression affecting contiguous genes via a long-range control element.

Although the underlying reason for CYGB down-regulation in TOC is unclear, a novel genetic mechanism appears to be involved. The magnitude of CYGB down-regulation in tylotic oesophageal biopsies greater than 70% exceeds the maximum 50% reduction that would be expected in an autosomal dominant disease where, by definition, the genetic defect affects only one allele. Furthermore, both alleles of CYGB appear to be equally repressed, thus excluding simple haploinsufficiency [which occurs in some cases of APC; (13Go)] as a disease mechanism. Instead, the data point to a novel trans-allele interaction and imply that a dominant mutation on one allele is down-regulating both alleles.

One explanation for this would be if the disease allele were capable of producing an antisense transcript that caused post-transcriptional down-regulation of both copies of CYGB via RNAi. Aberrant antisense transcription as a cause of genetic disease has previously been reported (14Go), although in that instance the abnormal transcript caused promoter methylation and repression only in cis. More recently, the transcriptional repression of the CDH1 gene by targeted double-stranded RNA in a cancer model has been described (15Go). A candidate for the origin of an antisense transcript in TOC is the FM8 gene, which overlaps CYGB in the opposite orientation. The data presented here do not provide evidence for an RNAi effect of the FM8 gene in the aetiology of this disease, as no tylosis-specific expression differences of FM8 were observed. However, we cannot exclude the possible existence of small changes in FM8 expression, novel splice variants, or the presence of other antisense transcripts.

Alternatively, down-regulation of CYGB might be transcriptional rather than post-transcriptional, and this could be regulated via an epigenetic mark. Recent evidence implicating FLJ22341 as a candidate ovarian cancer gene suggests an epigenetic mechanism to account for its complete down-regulation in this disease (11Go). Furthermore, germline methylation of one allele of the human MLH1 gene in two individuals with HNPCC and multiple cancers causes complete loss of protein expression in all cancer tissues [RNA expression was not investigated; (16Go)]. In plants, inter-allelic transfer of epigenetic marks (paramutation) has been observed (17Go,18Go), and similar phenomena have been reported in mice (19Go): this might account for the trans-allele repression seen in TOC. Trans-generational inheritance of epigenetic marks has also been described in the mouse (20Go) and is implied in humans by the presence of the germline MLH1 epimutation in normal somatic tissue from all three cell lineages in the two HNPCC patients and in 1/100 spermatozoa (16Go). The low level of methylation that we observed in oesophageal and lymphocyte DNA from tylotic individuals would be insufficient to cause transcriptional repression of the magnitude observed, and thus excludes methylation at the CpG sites investigated as being the primary heritable abnormality. However, transcriptional repression can be caused by histone-mediated epigenetic changes in the absence of accompanying DNA methylation (15Go), so an epigenetic origin for CYGB down-regulation is still possible. Alternatively, as CYGB is reported to be expressed only in cells of myofibroblast lineage (21Go,22Go) and not in lymphocytes (F.E.M.; unpublished data) or epithelial cells, our data cannot exclude the possibility of transcriptional repression being caused by methylation of the CYGB promoter solely in CYGB-expressing cells. Myofibroblasts constitute only a small percentage of an oesophageal biopsy, thus a high methylation level of the CYGB gene promoter confined to this cell type could be obscured by generally low methylation of the promoter in the bulk of the tissue.

Down-regulation of the CYGB gene could alternatively be explained as a result of the altered expression of another gene, i.e. as a secondary event. However, although it has been shown that gene regulatory elements may be placed as far as 1 MB away from the gene they affect (23Go), it would seem to be an extraordinary coincidence if a genetic alteration located within the TOC minimal region should act on a gene outside the region that then had a secondary effect on the CYGB gene located within the minimal region.

It is of note that a similarly located, though larger, minimal region of deletion on 17q25 has been described between D17S1817 and D17S751 (45 kb) in ovarian cancer (11Go). In the ovarian study, although CYGB was initially a candidate gene based on cell line expression data, it was excluded after analysis of a panel of 10 ovarian tumours. Instead the FLJ22341 gene was identified as the strongest candidate in ovarian cancer, but this gene is not implicated in familial oesophageal cancer in our study.

The possibility existed that we had missed a causative mutation in the CYGB gene during sequencing of heterozygote tylosis family members, although several intronic, non-disease-associated SNPs were identified (7Go). To exclude this, the exons and 3' UTR of CYGB have been re-sequenced using DNA derived from somatic cell hybrids containing either the normal or tylotic chromosome 17 (constructed for us by GMP Genetics, Waltham, MA, USA). No point mutations were detected in this gene. The presence of an inversion or deletion within CYGB was also excluded by successful PCR of fragments covering the gene using this same hybrid DNA. Large insertions and duplications have been excluded by Southern blotting (F.E.M.; PhD thesis).

The observation that sporadic squamous oesophageal cancer samples demonstrate increased methylation at the CYGB promoter when compared with adjacent normal tissue is interesting, given our results showing AI in the TOC region in this series of tumours. However, the number of samples tested is too small to determine if the two observations are mutually exclusive, and allelic analysis of the methylated promoter was not undertaken. Down-regulation of the CYGB gene was observed in cell lines derived from sporadic squamous oesophageal cancers compared with that observed in a myofibroblast cell line or in normal oesophageal biopsy, and this appeared to correlate with the amount of methylation at the CYGB promoter.

Thus, although the causative heritable genetic defect for TOC has not been identified, our data suggest that a novel genetic mechanism causes down-regulation of both alleles of CYGB and contributes to the phenotype. The defect is unlikely to be germline methylation, as current evidence suggests that this would be transmitted to offspring infrequently (16Go) rather than at the 50% frequency required for the autosomal dominant inheritance pattern of TOC. Furthermore, we have no evidence that the CYGB gene promoter is methylated in somatic tissues in the tylotic family members. We have also added to the data that indicates a possible role of CYGB in sporadic SCOC (10Go) and postulate that methylation of the CYGB promoter in these sporadic tumours may be one of two ‘hits’, together with AI, in the mechanism of CYGB inactivation in these tumours. This would be similar to the MLH1 gene inactivation observed in the cancers of two individuals with demonstrated germline epimutation (16Go).

How down-regulation of CYGB might cause the TOC phenotype is unclear, as the function of CYGB has not been fully elucidated. None of the SNPs identified in the intronic regions of the CYGB and FM8 genes are disease-specific and thus do not provide any clues as to the mechanism. CYGB is known to be up-regulated during hypoxia (24Go), tissue damage and cellular stress (22Go), so it could therefore be speculated that loss of its function affects the wound-healing/fibrosis pathway (22Go), thus leading to pathology at sites of constant low-level ‘injury’ (frictional and thermal stress). As CYGB is expressed in myofibroblasts (21Go,22Go) while TOC pathology occurs in epithelia, it is likely that an epithelial–mesenchymal interaction (25Go)—Vogelstein's ‘Landscaper effect’ (26Go)—is involved in TOC. Characterisation of the role of CYGB in such an intercellular cross talk will increase our understanding of both TOC and sporadic SCOC.


   MATERIALS AND METHODS
TOP
 ABSTRACT
 INTRODUCTION
 RESULTS
 DISCUSSION
 MATERIALS AND METHODS
REFERENCES
 
Tissues and cell lines
Oesophageal biopsy specimens were collected during routine endoscopy from 18 affected individuals in the UK tylosis family, 7 individuals with GORD and 10 individuals undergoing endoscopy for reasons unrelated to cancer, GORD or any other oesophageal pathology. Tissues were collected into RNAlater (Qiagen) and stored at –20°C until the preparation of RNA using RNeasy (Qiagen) or RNA and DNA using RNA/DNA kits (Qiagen).

The SCOC cell line OE21 was obtained from ECACC and the SCOC cell lines KYSE-510, KYSE-410, KYSE-270 and KYSE-140 were obtained from DSMZ (27). The myofibroblast cell line CCD-18Co was obtained from ATCC. All cancer cell lines were grown in RPMI 1640 supplemented with 10% newborn calf serum. The CCD-18Co cell line was grown in Eagle's MEM supplemented with non-essential amino acids and 10% fetal bovine serum. Cells were prepared for DNA and RNA isolation by washing the monolayers twice with ice-cold PBS then scraping the cells into RNAlater (Qiagen). RNA and DNA were prepared as for oesophageal biopsy tissue.

Relative multiplex RT–PCR
Two micrograms of oesophageal biopsy or cell line RNA was reverse transcribed with oligo-dT primers and relative multiplex RT–PCR was performed using 0.2 µM each primer. In order to obtain comparative PCR kinetics for CYGB and TBP multiplex reactions, 12% of the TBP primers contained a 3' dideoxy C, whereas the remaining 88% were functional. Forward primers were 5'-FAM labelled. TBP and HPRT primer sequences have previously been published (28Go,29Go). CYGB, FLJ22341, SThM and EVPL primer sequences, the paired control gene and the number of cycles determined to be within the exponential phase for each gene pair reaction are given in Table 2.


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  		Table 2. Primers, control genes and cycle numbers used for relative multiplex RT-PCR
 
Bisulphite pyrosequencing
Bisulphite pyrosequencing was used to study four CpG residues covering a NotI site in the CYGB promoter, which had previously been validated as a methylation target in lung cancer (F.E.M. et al.; unpublished data). One microgram DNA was treated with the EZ-DNA methylation kit (Zymo Research), and the region of interest was amplified using methylation independent primers: 5' biotin-GGGAATTGATTTAAAGTTTA 3' and 5' AAAAACCCAACTAAATCC 3'. Pyrosequencing was carried out on a PSQ96MA System (Biotage), using the primer 5' ACCCAACTAAATCCAC 3' (antisense). Data were analysed in the AQ mode to provide relative quantification of G/A nucleotide incorporation. The complete conversion of cytosine to uracil by bisulphite treatment was ensured by examining a non-CpG cytosine residue: this was 100% converted in all cases.


   ACKNOWLEDGEMENTS
 
This research was funded by Cancer Research UK (CRUK) grant number C7738/A2997, the North West Cancer Research fund and the Isle of Man Anticancer Association. TL and GX are funded by the Roy Castle Lung Cancer Foundation.

Conflict of Interest statement. The authors declare that they have no conflict of interests.


   REFERENCES
TOP
 ABSTRACT
 INTRODUCTION
 RESULTS
 DISCUSSION
 MATERIALS AND METHODS
 REFERENCES
 

  1. Ellis, A., Field, J.K., Field, A.E., Friedmann, P.S., Fryer, A., Howard, P., Leigh, I.M., Risk, J.M., Shaw, J.M. and Whittaker, J. (1994) Tylosis associated with carcinoma of the oesophagus and oral leukoplakia in a large Liverpool family—a review of six generations. Eur. J. Cancer Part B, Oral Oncol., 30B, 102–112.[CrossRef]

  2. Hennies, H.C., Hagedorn, M. and Reis, A. (1995) Palmoplantar keratoderma in association with carcinoma of the esophagus maps to chromosome 17q distal to the keratin gene cluster. Genomics, 29, 537–540.[CrossRef][ISI][Medline]

  3. Stevens, H.P., Kelsell, D.P., Bryant, S.P., Bishop, D.T., Spurr, N.K., Weissenbach, J., Marger, D., Marger, R.S. and Leigh, I.M. (1996) Linkage of an American pedigree with palmoplantar keratoderma and malignancy (palmoplantar ectodermal dysplasia type III) to 17q24. Literature survey and proposed updated classification of the keratodermas. Arch. Dermatol., 132, 640–651.[Abstract]

  4. Kelsell, D.P., Risk, J.M., Leigh, I.M., Stevens, H.P., Ellis, A., Hennies, H.C., Reis, A., Weissenbach, J., Bishop, D.T., Spurr, N.K. and Field, J.K. (1996) Close mapping of the focal non-epidermolytic palmoplantar keratoderma (PPK) locus associated with oesophageal cancer (TOC). Hum. Mol. Genet., 5, 857–860.[Abstract/Free Full Text]

  5. Risk, J.M., Ruhrberg, C., Hennies, H.C., Mills, H.S., Di Colandrea, T., Evans, K.E., Ellis, A., Watt, F.M., Bishop, D.T., Spurr, N.K. et al. (1999) Envoplakin, a possible candidate gene for focal NEPPK/esophageal cancer (TOC): the integration of genetic and physical maps of the TOC region on 17q25. Genomics, 59, 234–242.[CrossRef][ISI][Medline]

  6. Risk, J.M., Evans, K.E., Jones, J., Langan, J.E., Rowbottom, L., McRonald, F.E., Mills, H.S., Ellis, A., Shaw, J.M., Leigh, I.M. et al. (2002) Characterization of a 500 kb region on 17q25 and the exclusion of candidate genes as the familial Tylosis Oesophageal Cancer (TOC) locus. Oncogene, 21, 6395–6402.[CrossRef][ISI][Medline]

  7. Langan, J.E., Cole, C.G., Huckle, E.J., Byrne, S., McRonald, F.E., Rowbottom, L., Ellis, A., Shaw, J.M., Leigh, I.M., Kelsell, D.P. et al. (2004) Novel microsatellite markers and single nucleotide polymorphisms refine the tylosis with oesophageal cancer (TOC) minimal region on 17q25 to 42.5 kb: sequencing does not identify the causative gene. Hum. Genet., 114, 534–540.[CrossRef][ISI][Medline]

  8. von Brevern, M., Hollstein, M.C., Risk, J.M., Garde, J., Bennett, W.P., Harris, C.C., Muehlbauer, K.R. and Field, J.K., (1998) Loss of heterozygosity in sporadic oesophageal tumours in the tylosis oesophageal cancer (TOC) gene region of chromosome 17. Oncogene, 17, 2101–2105.[CrossRef][ISI][Medline]

  9. Iwaya, T., Maesawa, C., Ogasawara, S. and Tamura, G. (1998) Tylosis esophageal cancer locus on chromosome 17q25.1 is commonly deleted in sporadic human esophageal cancer. Gastroenterology, 114, 1206–1210.[CrossRef][ISI][Medline]

  10. Shahabi, M., Noori Daloii, M.R., Langan, J.E., Rowbottom, L., Jahanzad, E., Khoshbin, E., Taghikhani, M., Field, J.K. and Risk, J.M. (2004) An investigation of the tylosis with oesophageal cancer (TOC) locus in Iranian patients with oesophageal squamous cell carcinoma. Int. J. Oncol., 25, 389–395.[ISI][Medline]

  11. Presnau, N., Dewar, K., Forgetta, V., Provencher, D., Mes-Masson, A.M. and Tonin, P.N. (2005) Loss of heterozygosity and transcriptome analyses of a 1.2 Mb candidate ovarian cancer tumor suppressor locus region at 17q25.1-q25.2. Mol. Carcinogen., 43, 141–154.[Medline]

  12. Urban, S., Lee, J.R. and Freeman, M. (2001) Drosophila Rhomboid-1 defines a family of putative intramembrane serine proteases. Cell, 107, 173–182.[CrossRef][ISI][Medline]

  13. Venesio, T., Balsamo, A., Rondo-Spaudo, M., Varesco, L., Risio, M. and Ranzani, G.N. (2003) APC haploinsufficiency, but not CTNNB1 or CDH1 gene mutations, accounts for a fraction of familial adenomatous polyposis patients without APC truncating mutations. Lab. Invest., 83, 1859–1866.[CrossRef][ISI][Medline]

  14. Tufarelli, C., Stanley, J.A.S., Garrick, D., Sharpe, J.A., Ayyub, H., Wood, W.G. and Higgs, D.R. (2003) Transcription of antisense RNA leading to gene silencing and methylation as a novel cause of human genetic disease. Nat. Genet., 34, 157–165.[CrossRef][ISI][Medline]

  15. Ting, A.H., Schuebel, K.E., Herman, J.G. and Baylin, S.B. (2005) Short double-stranded RNA induces transcriptional gene silencing in human cancer cells in the absence of DNA methylation. Nat. Genet., 37, 906–910.[CrossRef][ISI][Medline]

  16. Suter, C.M., Martin, D.I.K. and Ward, R.L. (2004) Germline epimutation of MLH1 in individuals with multiple cancers. Nat. Genet., 36, 497–501.[CrossRef][ISI][Medline]

  17. Colot, V., Maloisel, L. and Rossignol, J.L. (1996) Interchromosomal transfer of epigenetic states in Ascobolus: transfer of DNA methylation is mechanistically related to homologous recombination. Cell, 86, 855–864.[CrossRef][ISI][Medline]

  18. Chandler, V.L., Eggleston, W.B. and Dorweiler, J.E. (2000) Paramutation in maize. Plant Mol. Biol., 43, 121–145.[CrossRef][ISI][Medline]

  19. Herman, H., Lu, M., Anggraini, M., Sikora, A., Chang, Y.J., Yoon, B.J. and Soloway, P.D. (2003) Trans-allele methylation and paramutation-like effects in mice. Nat. Genet., 34, 199–202.[CrossRef][ISI][Medline]

  20. Morgan, H.D., Sutherland, H.G.E., Martin, D.I.K. and Whitelaw, E. (1999) Epigenetic inheritance at the agouti locus in the mouse. Nat. Genet., 23, 314–318.[CrossRef][ISI][Medline]

  21. Schmidt, M., Gerlach, F., Avivi, A., Laufs, T., Wystub, S., Simpson, J.C., Nevo, E., Saaler-Reinhardt, S., Reuss, S., Hankeln, T. and Burmester, T. (2004) Cytoglobin is a respiratory protein in connective tissue and neurons, which is up-regulated by hypoxia. J. Biol. Chem., 279, 8063–8069.[Abstract/Free Full Text]

  22. Nakatani, K., Okuyama, H., Shimahara, Y., Saeki, S., Kim, D.H., Nakajima, Y., Seki, S., Kawada, N. and Yoshizato, K. (2004) Cytoglobin/STAP, its unique localization in splanchnic fibroblast-like cells and function in organ fibrogenesis. Lab. Invest., 84, 91–101.[CrossRef][ISI][Medline]

  23. Cook, P.R. (2003) Nongenic transcription, gene regulation and action at a distance. J. Cell Sci., 116, 4483–4491.[Abstract/Free Full Text]

  24. Fordel, E., Geuens, E., Dewilde, S., De Coen, W. and Moens, L. (2004) Hypoxia/ischemia and the regulation of neuroglobin and cytoglobin expression. IUBMB Life, 56, 681–687.[ISI][Medline]

  25. Desmouliere, A., Guyot, C. and Gabbiani, C. (2004) The stroma reaction myofibroblast: a key player in the control of tumor cell behaviour. Int. J. Dev. Biol., 48, 509–517.[CrossRef][ISI][Medline]

  26. Kinzler, K.W. and Vogelstein, B. (1998) Landscaping the cancer terrain. Science, 280, 1036–1037.[Free Full Text]

  27. Shimada, Y., Imamura, M., Wagata, T., Yamaguchi, N. and Tobe, T. (1992) Characterization of 21 newly established esophageal cancer cell lines. Cancer, 69, 277–284.[CrossRef][ISI][Medline]

  28. Savinainen, K.J., Saramaki, O.R., Linja, M.J., Bratt, O., Tammela, T.L.J., Isola, J.J. and Visakorpi, T. (2002) Expression and gene copy number analysis of ERBB2 oncogene in prostate cancer. Am. J. Pathol., 160, 339–345.[Abstract/Free Full Text]

  29. Dupont, M., Goldsborough, A., Levayer, T., Savare, J., Rey, J.M., Rossi, J.F., Demaille, J. and Lavabre-Bertrand, T. (2002) Multiplex fluorescent RT–PCR to quantify leukemic fusion transcripts. Biotechniques, 33, 158–164.[ISI][Medline]


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