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  • 1
    Abstract: BACKGROUND: Glyoxalase 1 is a key enzyme in the detoxification of reactive metabolites such as methylglyoxal and induced Glyoxalase 1 expression has been demonstrated for several human malignancies. However, the regulation and clinical relevance of Glyoxalase 1 in the context of head and neck squamous cell carcinoma has not been addressed so far. METHODS: Argpyrimidine modification as a surrogate for methylglyoxal accumulation and Glyoxalase 1 expression in tumor cells was assessed by immunohistochemical staining of tissue microarrays with specimens from oropharyngeal squamous cell carcinoma patients (n = 154). Prognostic values of distinct Glyoxalase 1 staining patterns were demonstrated by Kaplan-Meier, univariate and multivariate Cox proportional hazard model analysis. The impact of exogenous methylglyoxal or a Glyoxalase 1 inhibitor on the viability of two established tumor cell lines was monitored by a colony-forming assay in vitro. RESULTS: Glyoxalase 1 expression in tumor cells of oropharyngeal squamous cell carcinoma patients was positively correlated with the presence of Argpyrimidine modification and administration of exogenous methylglyoxal induced Glyoxalase 1 protein levels in FaDu and Cal27 cells in vitro. Cal27 cells with lower basal and methylglyoxal-induced Glyoxalase 1 expression were more sensitive to the cytotoxic effect at high methylgyoxal concentrations and both cell lines showed a decrease in colony formation with increasing amounts of a Glyoxalase 1 inhibitor. A high and nuclear Glyoxalase 1 staining was significantly correlated with shorter progression-free and disease-specific survival, and served as an independent risk factor for an unfavorable prognosis of oropharyngeal squamous cell carcinoma patients. CONCLUSIONS: Induced Glyoxalase 1 expression is a common feature in the pathogenesis of oropharyngeal squamous cell carcinoma and most likely represents an adaptive response to the accumulation of cytotoxic metabolites. Oropharyngeal squamous cell carcinoma patients with a high and nuclear Glyoxalase 1 staining pattern have a high risk for treatment failure, but might benefit from pharmacological targeting Glyoxalase 1 activity.
    Type of Publication: Journal article published
    PubMed ID: 28549423
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  • 2
    Keywords: EXPRESSION ; tumor ; carcinoma ; CELL ; Germany ; TYROSINE KINASE ; screening ; SITE ; SITES ; DISTINCT ; microarray ; PROTEIN ; TISSUE ; TUMORS ; primary ; GROWTH-FACTOR RECEPTOR ; FREQUENCY ; FREQUENCIES ; STAGE ; PROGRESSION ; immunohistochemistry ; ABERRATIONS ; HEAD ; ONCOPROTEIN ; CARCINOMAS ; NECK ; squamous cell carcinoma ; GREECE ; gene amplification ; head and neck ; laryngeal carcinoma ; OROPHARYNGEAL ; C-MYC ; CANCER PATIENTS ; CYCLIN D1 OVEREXPRESSION ; cytogenetic aberration ; head and neck squamous cell carcinoma (HNSCC) ; immunohistochemistry (IHC) ; MICROARRAY ANALYSIS ; oncoprotein overexpression ; OVEREXPRESSION ; POOR-PROGNOSIS ; tissue microarray (TMA) ; tumor classification
    Abstract: Background: Tissue microarray (TMA) analysis is a high-throughput approach that allows the screening of large tumor collectives for cytogenetic aberrations. In this study, a TMA of a large collection of clinically well-defined primary squamous cell carcinomas of the head and neck (HNSCC) was used to determine the expression of several oncoproteins. Materials and Methods: A TMA containing 547 primary HNSCC was used for the analysis of cyclinD1, c-myc, erbb1 and erbb2 expression by immunohistochemistry (IHC). Results: CyclinD1 and c-myc were overexpressed at higher frequencies in primary pharyngeal and laryngeal carcinomas compared with primary oral carcinomas (p 〈 0.001 and p 〈 0.001), while erbb1 and erbb2 overexpression was associated with oral site (p 〈 0.001 and p = 0.04, respectively). Furthermore, cyclinD1 overexpression correlated with stage IV primary carcinomas (p = 0.04). Conclusion: HNSCC is a heterogenous group of tumors, which, depending on anatomic sites and clinical stage, shows variable expressions of the oncoproteins described. This indicates a specific pathogenic role of these oncoproteins in different subtypes of HNSCC and may have therapeutic implications
    Type of Publication: Journal article published
    PubMed ID: 14666705
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  • 3
    Keywords: SPECTRA ; EXPRESSION ; tumor ; carcinoma ; CELL ; Germany ; COHORT ; SITE ; SITES ; DISTINCT ; microarray ; PROTEIN ; TISSUE ; TUMORS ; PATIENT ; DNA ; prognosis ; DOMAIN ; SIGNAL ; STAGE ; PROGRESSION ; AMPLIFICATION ; immunohistochemistry ; MUTATION ; TUMOR PROGRESSION ; inactivation ; p53 ; MUTATIONS ; HUMAN-PAPILLOMAVIRUS ; SQUAMOUS-CELL CARCINOMA ; HEAD ; PROGNOSTIC-SIGNIFICANCE ; NECK ; squamous cell carcinoma ; PROGNOSTIC VALUE ; PREVALENCE ; head and neck ; OVEREXPRESSION ; SEQUENCE-ANALYSIS ; CYCLE CONTROL ; protein expression ; CELL CARCINOMA ; ADVANCED BREAST-CANCER ; ADVANCED LARYNGEAL CARCINOMA ; GENE ALTERATIONS ; head and neck cancer ; mutation and expression ; PROTEIN OVEREXPRESSION ; SUPPRESSOR GENE ; SYSTEMIC THERAPY ; tumor sites
    Abstract: The tumor site is a strong clinical factor in head and neck squamous cell carcinoma (HNSCC). To clarify the biologic and clinical role of p53 alterations in HNSCC, we have examined the prevalence and the nature of p53 alterations in a large cohort of tumors from the different sites. For immunohistochemical analysis of p53 protein expression, we introduced tyramide signal amplification immunohistochemistry (TSA-IHC) on a tissue microarray. This allowed the discrimination between normal low-level expression and reduced or lost expression. Two hundred fifty-three tumors were subjected to mutational analysis by genomic DNA sequencing, employing also the p53 GeneChip from Affymetrix. The prevalence of all p53 alterations, i.e., mutations, overexpression and loss of expression, was significantly higher in hypopharyngeal tumors than in the other sites (p = 0.001). Laryngeal tumors showed the lowest rate of p53 alterations, but revealed a distinct mutation spectrum: most mutations affected exon 5 (p = 0.013) and the S2' domain (p = 0.002), and most hot-spot 248 mutations occurred in the larynx (p 〈 0.001). Sequencing by p53 GeneChip technology was shown to be only insignificantly more sensitive than dideoxy sequencing. In agreement with p53 mutations occurring prior to invasiveness, their prevalence did not increase with tumor stage, and all mutation classes lacked prognostic significance. The large patient cohort of this study showed that p53 is differentially affected in the different tumor sites of the head and neck, but its mode of inactivation does not play a major role in tumor progression. (C) 2004 Wiley-Liss, Inc
    Type of Publication: Journal article published
    PubMed ID: 15239130
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  • 4
    Keywords: EXPRESSION ; INHIBITOR ; tumor ; carcinoma ; Germany ; KINASE ; TYROSINE KINASE ; GENE ; HYBRIDIZATION ; microarray ; PROTEIN ; TISSUE ; TUMORS ; TYROSINE KINASE INHIBITOR ; IN-SITU ; immunohistochemistry ; NUMBER ; PATHOGENESIS ; FISH ; MUTATIONS ; SQUAMOUS-CELL CARCINOMA ; HEAD ; NECK ; PREVALENCE ; FLUORESCENCE ; OVEREXPRESSION ; imatinib ; fluorescence in situ hybridization ; GAINS ; C-KIT ; ADENOID CYSTIC CARCINOMA ; GASTROINTESTINAL STROMAL TUMORS ; INHIBITORS ; in situ hybridization ; salivary gland tumor ; AMPLIFICATIONS ; GLAND ; intensity ; SUBTYPE ; TUMOR TISSUE ; KINASE INHIBITORS ; SUBTYPES ; KIT ; tissue microarray ; tissue microarray analysis
    Abstract: Adenoid cystic carcinoma (ACC) of the salivary gland is characterized by a prolonged but inevitably unfavorable clinical course. Recent studies suggested the transmembrane tyrosine kinase KIT to be involved in ACC pathogenesis. To investigate KIT expression in histologically defined subgroups of ACC and to clarify whether KIT gene copy number gain contributes to KIT overexpression, tumor tissue microarray sections including 55 ACC tumors were analyzed by fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC). The prevalence of positive KIT immunostaining was 89% (49/55). Strong immunostaining of KIT was only found in cribriform and tubular but never in solid subtypes (p = 0.02). Average KIT staining intensity was higher in cribriform and tubular (n = 37) compared to solid (n = 18) ACC subtypes (p = 0.005). FISH analysis revealed copy number gains of the KIT gene in 6.1% (3/49) of tumors analyzed. Our results implicate that specific KIT tyrosine kinase inhibitors such as imatinib, might be used in future therapeutic approaches against subgroups of ACC. (c) 2005 Elsevier Ltd. All rights reserved
    Type of Publication: Journal article published
    PubMed ID: 16054424
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  • 5
    Keywords: EXPRESSION ; tumor ; carcinoma ; Germany ; GENE ; GENES ; HYBRIDIZATION ; microarray ; PROTEIN ; TISSUE ; TUMORS ; DNA ; PROGRESSION ; AMPLIFICATION ; COMPARATIVE GENOMIC HYBRIDIZATION ; microarrays ; HEAD ; NECK ; squamous cell carcinoma ; PROGNOSTIC VALUE ; CYCLIN D1 OVEREXPRESSION ; OVEREXPRESSION ; POOR-PROGNOSIS ; CHROMOSOMAL IMBALANCES ; CHRONIC LYMPHOCYTIC-LEUKEMIA ; CANDIDATE GENES ; tissue microarray analysis ; SPECIMENS ; ARRAY CGH
    Abstract: Chromosomal band 11q13 is frequently amplified in oral squamous cell carcinoma (OSCC) and assumed to be critically involved in tumor initiation and progression by proto-oncogene activation. Though cyclin D1 (CCND1) is supposed to be the most relevant oncogene, several additional putative candidate genes are inside this chromosomal region, for which their actual role in tumorigenesis still needs to be elucidated. To characterize the 11q13 amplicon in detail, 40 OSCCs were analyzed by comparative genomic hybridization to DNA microarrays (matrix-CGH) containing BAC clones derived from chromosomal band 11q13. This high-resolution approach revealed a consistent amplicon about 1.7 Mb in size including the CCND1 oncogene. Seven BAC clones covering FGF3, EMS1, and SHANK2 were shown to be frequently coamplified inside the CCND1 amplicon. Subsequent analysis of tissue microarrays; by FISH revealed amplification frequencies of 36.8% (88/239) for CCND1, 34.3% (60/ 175) for FGF3, 37.4% (68/182) for EMS1, and 36.3% (61/168) for SHANK2. Finally, quantitative mRNA expression analysis demonstrated consistent overexpression of CCND1 in all tumors and of EMS1 and SHANK2 in a subset of specimens with 11q13 amplification, but no expression of FGF3 in any of the cases. Our study underlines the critical role of CCND1 in OSCC development and additionally points to the functionally related genes EMS1 and SHANK2, both encoding for cytoskeleton-associated proteins, which are frequently coamplified with CCND1 and therefore could cooperatively contribute to OSCC pathogenesis. (c) 2005 Wiley-Liss, Inc
    Type of Publication: Journal article published
    PubMed ID: 16235239
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  • 6
    Keywords: EXPRESSION ; GROWTH ; proliferation ; carcinoma ; Germany ; INHIBITION ; PATHWAY ; DISTINCT ; GENE ; GENES ; microarray ; PROTEIN ; DIFFERENTIATION ; TISSUE ; TUMORS ; SKIN ; IN-SITU ; AMPLIFICATION ; COPY NUMBER ; immunohistochemistry ; NUMBER ; MUTATIONS ; ONCOGENE ; HUMAN HOMOLOG ; HEAD ; PREVALENCE ; PRECURSORS ; EFFECTOR ; basal cell carcinoma ; N-MYC ; CELL CARCINOMA ; SUBSET ; fluorescence in situ hybridisation ; LOCUS ; tissue microarray ; NMYC ; HUMAN NEUROBLASTOMA ; SPECIMENS
    Abstract: Formation of basal cell carcinoma (BCC) has been linked to deregulation in the sonic hedgehogh (Shh) signalling pathway. Though mutations of the genes, PTCHI and SMO, are known to be involved in aberrant Shh signalling, the distinct downstream effectors of these genes are poorly described. Studies have indicated that the NMYC oncogene is a potential Shh downstream effector. To assess the expression of Nmyc protein and gene copy numbers of the NMYC gene locus in a representative BCC tumour collection, immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH) were performed on 273 BCC specimens of different growth patterns and anatomic localisations on tissue microarray (TMA) sections. High Nmyc protein expression was detected in 72.7% (160/220) of all BCC specimens. Strong Nmyc immunopositivity was more frequently found in infiltrative BCCs compared to nodular/superficial BCCs (p=0.005), and in BCCs of the head compared to BCCs of other anatomic localisations (p=0.021). The prevalence of NMYC copy number gains was 17.5% (37/211), including three tumours with nodular differentiation that exhibited a distinct high-level amplification of the NMYC locus. These data indicate that high expression of the Shh downstream mediator, Nmyc, is a frequent event in BCC, predominantly in more aggressive subtypes. Although the NMYC copy number gain found in a subset of cases might contribute to this aberrant Nmyc protein expression by a gene dosage effect, our data suggests that Nmyc protein can also be induced by aberrant Shh signalling, acting as an effector molecule of the Shh pathway. Novel systemic anti-sense NMYC inhibition strategies could be a promising option for therapy-refractory BCC
    Type of Publication: Journal article published
    PubMed ID: 16596176
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  • 7
    Keywords: EXPRESSION ; carcinoma ; CELL ; Germany ; human ; THERAPY ; GENE ; HYBRIDIZATION ; microarray ; PROTEIN ; TISSUE ; SURGERY ; ACTIVATION ; CONTRAST ; TARGET ; IN-SITU ; PROGRESSION ; AMPLIFICATION ; COMPARATIVE GENOMIC HYBRIDIZATION ; COPY NUMBER ; immunohistochemistry ; CATALYTIC SUBUNIT ; NUMBER ; metastases ; CANCER-CELLS ; HEAD ; CARCINOMAS ; NECK ; squamous cell carcinoma ; pathology ; FLUORESCENCE ; fluorescence in situ hybridization ; protein expression ; in situ hybridization ; CELL CARCINOMA ; development ; methods ; tissue microarray ; tissue microarray analysis ; CANDIDATE ; SQUAMOUS-CELL ; reverse transcriptase ; human telomerase ; IMMORTALITY ; oral squamous cell carcinoma ; TERT
    Abstract: BACKGROUND: Gene copy number gain of chromosomal arm 5p is frequently found in oral squamous cell carcinoma (OSCC) suggesting the activation of proto-oncogenes. TERT is a candidate gene encoding for human telomerase reverse transcriptase (hTERT). The aim of the present study was to elucidate the relevance of TERT copy number gain and high hTERT expression in OSCC. METHODS: Fluorescence in situ hybridization (FISH) for TERT and immunohistochemistry (IHC) for hTERT were performed to analyze TERT copy numbers and hTERT expression, respectively, on tissue microarray (TMA) sections including n = 247 OSCC and n = 105 pharyngeal and laryngeal squamous cell carcinomas (PSCC/LSCC). RESULTS: Increased hTERT protein expression was more frequently found in OSCC (71.1 %, 155/218) than in PSCC/LSCC (36.0%, 35/89) (13 〈 0.001). By contrast, specific TERT amplifications were less common in OSCC (2.1%, 4/191) compared with PSCC/LSCC (9.9%, 8/81) (P = 0.047). CONCLUSIONS: High hTERT expression is a frequent finding in OSCC. It might be a promising target for the development of specific anti-neoplastic therapy approaches
    Type of Publication: Journal article published
    PubMed ID: 17448136
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  • 8
    Keywords: APOPTOSIS ; EXPRESSION ; GROWTH ; proliferation ; tumor ; carcinoma ; CELL ; FACTOR RECEPTOR ; Germany ; human ; KINASE ; PATHWAY ; PATHWAYS ; DISTINCT ; GENE ; GENE-EXPRESSION ; GENES ; microarray ; PROTEIN ; PROTEINS ; SAMPLE ; SAMPLES ; TISSUE ; ACTIVATION ; primary ; PROTEIN-KINASE ; ASSOCIATION ; MAP KINASE ; score ; STAGE ; NEOPLASIA ; immunohistochemistry ; gene expression ; metastases ; ABERRATIONS ; SIGNALING PATHWAY ; RELIABILITY ; HEAD ; squamous cell carcinoma ; GROWTH-FACTOR-BETA ; MICROARRAY ANALYSIS ; gene expression profiling ; CHRONIC LYMPHOCYTIC-LEUKEMIA ; protein expression ; EPIDERMAL-GROWTH-FACTOR ; NECK-CANCER ; signaling ; molecular ; CELL CARCINOMA ; ONCOLOGY ; INCREASE ; analysis ; CHIP ; USA ; lymph node metastases ; SQUAMOUS-CELL ; HUMAN HEPATOCELLULAR-CARCINOMA ; SET ; COLLECTION ; DETECT ; MAP-KINASE ; GENE-ONTOLOGY
    Abstract: In an attempt to further elucidate the pathomechanisms in oral squamous cell carcinoma (OSCC), gene expression profiling was performed using a whole-transcriptome chip that contains 35,035 gene-specific 70mere oligonucleotides (Human OligoSet 4.0; Operon, Cologne, Germany) to a set of 35 primary OSCCs. Altogether, 7390 genes were found differentially expressed between OSCC tumor samples and oral mucosa. To characterize the major biologic processes in this tumor collection, MAPPFinder, a component of GenMAPP version 2.1, was applied to this data set to generate a statistically ranked list of molecular signaling pathways. Among others, cancer-related pathways, such as mitogen-activated protein (MAP) kinase signaling (z score = 4.6, P 〈 .001), transforming growth factor-beta signaling (z score = 3.0, P = .015), and signaling pathways involved in apoptosis (z score = 2.1, P = .037), were found deregulated in the OSCC collection analyzed. Focusing on the MAP kinase signaling pathway, subsequent tissue microarray analyses by immunohistochemistry revealed an increase in protein expression of MAP kinase-related proteins ERK1 in 22.8% (48 of 209) and ERK5 in 27.4% (76 of 277), respectively. An association of high ERK5 but not of high ERK1 expression with advanced tumor stage and the presence of lymph node metastases was found (P = .008 and P = .016, respectively). Our analysis demonstrates the reliability of the combined approach of gene expression profiling, signaling pathway analyses, and tissue microarray analysis to detect novel distinct molecular aberrations in OSCC
    Type of Publication: Journal article published
    PubMed ID: 18472963
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  • 9
    Keywords: CANCER ; EXPRESSION ; TUMORS ; RECURRENCE ; REVEALS ; nucleolus ; MYB-BINDING PROTEIN
    Abstract: ABSTRACT: BACKGROUND: Head and neck squamous cell carcinoma (HNSCC) is one of the most prevalent and lethal cancers worldwide and mortality mostly results from loco-regional recurrence and metastasis. Despite its significance, our knowledge on molecular, cellular and environmental mechanisms that drive disease pathogenesis remains largely elusive, and there are limited therapeutic options, with only negligible clinical benefit. METHODS: We applied global gene expression profiling with samples derived from a recently established mouse model for oral cancer recurrence and identified a list of genes with differential expression between primary and recurrent tumors. RESULTS: One differentially expressed gene codes for Myb-binding protein 1a (MYBBP1A), which is known as a transcriptional co-regulator that physically interacts with nuclear transcription factors, such as NFkappaB and p53. We confirmed significantly reduced MYBBP1A protein levels on tissue sections of recurrent mouse tumors compared to primary tumors by immunohistochemistry, and found aberrant MYBBP1A protein levels also in tumor samples of HNSCC patients. Interestingly, silencing of MYBBP1A expression in murine SCC7 and in human HNSCC cell lines elicited increased migration but decreased cell growth. CONCLUSION: We provide experimental evidence that MYBBP1A is an important molecular switch in the regulation of tumor cell proliferation versus migration in HNSCC and it will be a major challenge for the future to proof the concept whether regulation MYBBP1A expression and/or function could serve as a novel option for anti-cancer therapy.
    Type of Publication: Journal article published
    PubMed ID: 22339894
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  • 10
    Keywords: DNA methylation ; RETINOIC ACID ; EPIGENETIC INACTIVATION ; NECK-CANCER ; TUMOR-SUPPRESSOR ; PROMOTER METHYLATION ; ONCOGENIC HUMAN-PAPILLOMAVIRUS ; ACTIVE HUMAN-PAPILLOMAVIRUS ; HIGH VIRAL LOAD ; TONSILLAR CANCER
    Abstract: High-risk types of human papilloma virus (HPV) are increasingly associated with oropharyngeal squamous cell carcinoma (OPSCC). Strikingly, patients with HPV-positive OPSCC are highly curable with ionizing radiation and have better survival compared with HPV-negative patients, but the underlying molecular mechanisms remain poorly understood. We applied an array-based approach to monitor global changes in CpG island hypermethylation between HPV-negative and HPV-positive OPSCCs and identified a specific pattern of differentially methylated regions that critically depends on the presence of viral transcripts. HPV-related alterations were confirmed for the majority of candidate gene promoters by mass spectrometric, quantitative methylation analysis. There was a significant inverse correlation between promoter hypermethylation of ALDH1A2, OSR2, GATA4, GRIA4, and IRX4 and transcript levels. Interestingly, Kaplan-Meier analysis revealed that a combined promoter methylation pattern of low methylation levels in ALDH1A2 and OSR2 promoters and high methylation levels in GATA4, GRIA4, and IRX4 promoters was significantly correlated with improved survival in 3 independent patient cohorts. ALDH1A2 protein levels, determined by immunohistochemistry on tissue microarrays, confirmed the association with clinical outcome. In summary, our study highlights specific alterations in global gene promoter methylation in HPV-driven OPSCCs and identifies a signature that predicts the clinical outcome in OPSCCs.
    Type of Publication: Journal article published
    PubMed ID: 23635773
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