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Purpose 2-deoxy-2-[18F]fluoro-d-glucose ([18F]FDG) uptake is a marker of metabolic activity and is therefore used to measure the inflammatory state of several tissues. This radionuclide marker is transported through the cell membrane via glucose transport proteins (GLUTs). The aim of this study is to investigate whether insulin resistance (IR) or inflammation plays a role in [18F]FDG uptake in adipose tissue (AT). Procedures This study consisted of an in vivo clinical part and an ex vivo mechanistic part. In the clinical part, [18F]FDG uptake in abdominal visceral AT (VAT) and subcutaneous AT (SAT) was determined using PET/CT imaging in 44 patients with early type 2 diabetes mellitus (T2DM) (age 63 [54–66] years, HbA1c [6.3 ± 0.4 %], HOMA-IR 5.1[3.1–8.5]). Plasma levels were measured with ELISA. In the mechanistic part, AT biopsies obtained from 8 patients were ex vivo incubated with [18F]FDG followed by autoradiography. Next, a qRT-PCR analysis was performed to determine GLUT and cytokine mRNA expression levels. Immunohistochemistry was performed to determine CD68+ macrophage infiltration and GLUT4 protein expression in AT. Results In vivo VAT [18F]FDG uptake in patients with T2DM was inversely correlated with HOMA-IR (r = − 0.32, p = 0.034), and positively related to adiponectin plasma levels (r = 0.43, p = 0.003). Ex vivo [18F]FDG uptake in VAT was not related to CD68+ macrophage infiltration, and IL-1ß and IL-6 mRNA expression levels. Ex vivo VAT [18F]FDG uptake was positively related to GLUT4 (r = 0.83, p = 0.042), inversely to GLUT3 (r = − 0.83, p = 0.042) and not related to GLUT1 mRNA expression levels. Conclusions In vivo [18F]FDG uptake in VAT from patients with T2DM is positively correlated with adiponectin levels and inversely with IR. Ex vivo [18F]FDG uptake in AT is associated with GLUT4 expression but not with pro-inflammatory markers. The effect of IR should be taken into account when interpreting data of [18F]FDG uptake as a marker for AT inflammation.

Oral and oropharyngeal squamous cell carcinoma (OOSCC) have a low survival rate, mainly due to metastasis to the regional lymph nodes. For optimal treatment of these metastases, a neck dissection is required; however, inaccurate detection methods results in under- and over-treatment. New DNA prognostic methylation biomarkers might improve lymph node metastases detection. To identify epigenetically regulated genes associated with lymph node metastases, genome-wide methylation analysis was performed on 6 OOSCC with (pN+) and 6 OOSCC without (pN0) lymph node metastases and combined with a gene expression signature predictive for pN+ status in OOSCC. Selected genes were validated using an independent OOSCC cohort by immunohistochemistry and pyrosequencing, and on data retrieved from The Cancer Genome Atlas. A two-step statistical selection of differentially methylated sequences revealed 14 genes with increased methylation status and mRNA downregulation in pN+ OOSCC. RAB25, a known tumor suppressor gene, was the highest-ranking gene in the discovery set. In the validation sets, both RAB25 mRNA (P = 0.015) and protein levels (P = 0.012) were lower in pN+ OOSCC. RAB25 mRNA levels were negatively correlated with RAB25 methylation levels (P < 0.001) but RAB25 protein expression was not. Our data revealed that promoter methylation is a mechanism resulting in downregulation of RAB25 expression in pN+ OOSCC and decreased expression is associated with lymph node metastasis. Detection of RAB25 methylation might contribute to lymph node metastasis diagnosis and serve as a potential new therapeutic target in OOSCC.

Hypermethylation is an important mechanism for the dynamic regulation of gene expression, necessary for metastasizing tumour cells. Our aim is to identify methylation tumour markers that have a predictive value for the presence of regional lymph node metastases in patients with oral and oropharyngeal squamous cell carcinoma (OOSCC). Significantly differentially expressed genes were retrieved from four reported microarray expression profiles comparing pN0 and pN+ head-neck tumours, and one expression array identifying functionally hypermethylated genes. Additional metastasis-associated genes were included from the literature. Thus genes were selected that influence the development of nodal metastases and might be regulated by methylation. Methylation-specific PCR (MSP) primers were designed and tested on 8 head-neck squamous cell carcinoma cell lines and technically validated on 10 formalin-fixed paraffin-embedded (FFPE) OOSCC cases. Predictive value was assessed in a clinical series of 70 FFPE OOSCC with pathologically determined nodal status. Five out of 28 methylation markers (OCLN, CDKN2A, MGMT, MLH1 and DAPK1) were frequently differentially methylated in OOSCC. Of these, MGMT methylation was associated with pN0 status (P = 0.02) and with lower immunoexpression (P = 0.02). DAPK1 methylation was associated with pN+ status (P = 0.008) but did not associate with protein expression. In conclusion, out of 28 candidate genes, two (7%) showed a predictive value for the pN status. Both genes, DAPK1 and MGMT, have predictive value for nodal metastasis in a clinical group of OOSCC. Therefore DNA methylation markers are capable of contributing to diagnosis and treatment selection in OOSCC. To efficiently identify additional new methylation markers, genome-wide methods are needed.

Background: Accurate assessment of the prevalence of the human papilloma virus (HPV) in oropharyngeal tumours (OpSCC) is important because HPV-positive OpSCC are consistently associated with an improved overall survival. Recently, an algorithm has become available that reliably detects clinically relevant HPV in tumour tissue, however, no complete cohorts have been tested. The aim was to determine the prevalence of active high-risk HPV infection in a complete cohort of OpSCC collected over a 16-year period.Methods: Using a triple algorithm of p16 immunohistochemistry, HPV-BRISH and HPV-PCR, we assessed the prevalence of active HPV infection in all OpSCC diagnosed in our hospital from 1997 to 2012 (n = 193) and a random selection of 200 oral tumours (OSCC).Results: Forty-seven OpSCC (24%) were HPVGP PCR-positive; 42 cases were HPV16+, 1 HPV18+, 3 HPV33+ and 1 HPV35+. Brightfield in situ hybridisation did not identify additional HPV-positive cases. Human papilloma virus-associated tumour proportion increased from 13% (1997-2004) to 30% (2005-2012). Human papilloma virus-positivity was an independent predictor for longer disease-specific survival (HR = 0.22; 95% CI: 0.10-0.47). Only one OSCC was HPV+.Conclusions: In our cohort, the incidence of HPV-associated OpSCC is low but increasing rapidly. The strict detection algorithm, analysis of disease-specific survival and the complete cohort, including palliatively treated patients, may influence the reported prevalence and prognostic value of HPV in OpSCC.

Purpose: To assess the prevalence of EGFRvIII, a specific variant of EGFR (epidermal growth factor receptor), in 3 well-defined cohorts of head and neck squamous cell carcinoma (HNSCC).Methods and Materials: Immunohistochemistry for the specific detection of EGFRvIII using the L8A4 antibody was optimized on formalin-fixed, paraffin-embedded tissue using glioblastoma tissue. It was compared with EGFR and EGFRvIII RNA expression using a specific reverse transcription-polymerase chain reaction also optimized for formalin-fixed, paraffin-embedded tissue. Tissue microarrays including 531 HNSCCs of various stages with complete clinicopathologic and follow-up data were tested for the presence of EGFRvIII.Results: None of the 531 cases showed EGFRvIII protein expression. Using an immunohistochemistry protocol reported by others revealed cytoplasmic staining in 8% of cases. Reverse transcription-polymerase chain reaction for the EGFRvIII transcript of the 28 highest cytoplasmic staining cases, as well as 69 negative cases, did not show expression in any of the tested cases, suggesting aspecific staining by a nonoptimal protocol.Conclusions: The EGFRvIII mutation is not present in HNSCC. Therefore, EGFRvIII does not influence treatment response in HNSCC and is not a usable clinical prognostic marker. (C) 2014 Elsevier Inc.

Objectives: Adequate treatment of oral and oropharyngeal squamous cell carcinoma (OSCC) is dependent on correctly predicting the presence of lymph node metastases. Current methods to diagnose nodal metastases partly result in overtreatment with associated morbidity and undertreatment with decreased disease-free survival. E-cadherin has been studied extensively as potential marker for lymph node metastases. EpCAM and claudin-7 have a functional relationship with E-cadherin, forming a complex that promotes tumourigenicity in vitro. We hypothesize that the co-expression patterns of these related molecules is a better prognostic marker for nodal status and regional recurrences.Materials and methods: We constructed separate tissue microarrays of tumour centre and tumour invasive front of 227 OSCC with complete clinicopathological and follow-up data, including HPV status, and performed immunohistochemistry for these molecules.Results: Lack of E-cadherin and presence of cytoplasmic EpCAM expression in the tumour front were predictive for nodal metastasis, but no co-expression pattern was found clinically relevant. Lack of claudin-7 in the tumour centre was highly and independently predictive for shorter regional disease-free survival (HR = 0.19; 95% CI: 0.06-0.62) and disease-specific survival (HR = 0.43; 95% CI: 0.21-0.87). High-risk HPV was not associated with any marker.Conclusions: The expression of E-cadherin and EpCAM, depending on the specific tumour sublocalization, is predictive for nodal status. However, co-expression did not improve the prediction of nodal status, indicating that the proposed in vitro complex is not functional in clinical samples. Additionally, lack of claudin-7 expression in the tumour centre may be used to identify patients with increased risk for regional recurrence. (C) 2013 Elsevier Ltd. All rights reserved.

AimsThe Fas-associated death domain gene (FADD) is often overexpressed in squamous cell carcinoma of the head and neck (HNSCC), and is considered to be a driver gene in amplification of the chromosomal 11q13.3 region. Amplification of 11q13.3 is associated with increased metastasis in HNSCC and breast cancer. The aim of this study was to investigate the association between FADD protein expression in advanced-stage HNSCC and clinicopathological features and outcome.Methods and resultsTumour tissues of 177 HNSCC patients uniformly treated with primary surgery and postoperative radiotherapy were collected. FADD expression was assessed on pretreatment tumour biopsies using immunohistochemistry. High FADD expression was detected in 44% of the HNSCC patients. High expression was associated with an increased rate of lymph node metastasis (P=0.001) and with a shorter distant metastasis-free interval (DMFI) (HR 2.6, 95% CI 1.0-6.7, P=0.046) when lymph node metastases were present.ConclusionsOur data show that an increase in FADD expression is associated with a higher incidence of lymph node metastasis at presentation, and with shorter DMFI when lymph node metastases are present. High FADD expression in the primary tumour could be a useful marker to select patients for systemic treatment strategies that reduce the risk of distant metastases.

Purpose: We recently reported on the identification of the Fas-associated death domain (FADD) as a possible driver of the chromosome 11q13 amplicon and the association between increased FADD expression and disease-specific survival in advanced-stage laryngeal carcinoma. The aim of this study was to examine whether expression of FADD and its Ser194-phosphorylated isoform (pFADD) predicts local control in patients with early-stage glottic carcinoma primarily treated with radiotherapy only.Methods and Materials: Immunohistochemical staining for FADD and pFADD was performed on pretreatment biopsy specimens of 92 patients with T1-T2 glottic squamous cell carcinoma primarily treated with radiotherapy between 1996 and 2005. Cox regression analysis was used to correlate expression levels with local control.Results: High levels of pFADD were associated with significantly better local control (hazard ratio, 2.40; 95% confidence interval, 1.04-5.55; p = 0.040). FADD overexpression showed a trend toward better local control (hazard ratio, 3.656; 95% confidence interval, 0.853-15.663; p = 0.081). Multivariate Cox regression analysis showed that high pFADD expression was the best predictor of local control after radiotherapy.Conclusions: This study showed that expression of phosphorylated FADD is a new prognostic biomarker for better local control after radiotherapy in patients with early-stage glottic carcinomas. (C) 2012 Elsevier Inc.

BACKGROUND: For locally advanced squamous cell carcinoma of the head and neck (HNSCC), the recurrence rate after surgery and postoperative radiotherapy is between 20 and 40%, and the 5- year overall survival rate is similar to 50%. Presently, no markers exist to accurately predict treatment outcome. Expression of proteins in the human epidermal growth factor receptor (EGFR) pathway has been reported as a prognostic marker in several types of cancer.METHODS: The aim of this study was to investigate the prognostic value of proteins in the EGFR pathway in HNSCC. For this purpose, we collected surgically resected tissue of 140 locally advanced head and neck cancer patients, all treated with surgery and postoperative radiotherapy.RESULTS: In a multivariate analysis, expression of the phosphatase and tensin homologue deleted on chromosome 10 (PTEN) was significantly related to worse locoregional control (LRC; HR: 2.2, 95% CI: 1.1-4.6; P = 0.03), independent of lymph node metastases (HR: 5.6, 95% CI: 1.2-27.4; P = 0.03) and extranodal spread (HR: 2.7; 95% CI: 1.2- 6.5; P = 0.02). In vitro clonogenic radiosensitivity assays confirmed that overexpression of PTEN resulted in increased radioresistance.CONCLUSION: Our study is the first report showing that expression of PTEN mediates radiosensitivity in vitro and that increased expression in advanced HNSCC predicts worse LRC. British Journal of Cancer (2010) 102, 1778-1785. doi: 10.1038/sj.bjc.6605707 www.bjcancer.com Published online 25 May 2010 (C) 2010 Cancer Research UK

Amplification of the 11q13 region is one of the most frequent aberrations in squamous cell carcinomas of the head and neck region (HNSCC). Amplification of 11q13 has been shown to correlate with the presence of lymph node metastases and decreased survival. The 11q13.3 amplicon carries numerous genes including cyclin D1 and cortactin. Recently, we reported that FADD becomes overexpressed upon amplification and that FADD protein expression predicts for lymph node positivity and disease-specific mortality. However, the gene within the 11q13.3 amplicon responsible for this correlation is yet to be identified. In this paper, we compared, using immunohistochemical analysis for cyclin D1, FADD and cortactin in a series of 106 laryngeal carcinomas which gene correlates best with lymph node metastases and increased disease-specific mortality. Univariate Cox regression analysis revealed that high expression of cyclin D1 (P = 0.016), FADD (P = 0.003) and cortactin (P = 0.0006) predict for increased risk to disease- specific mortality. Multivariate Cox analysis revealed that only high cortactin expression correlates with disease- specific mortality independent of cyclin D1 and/or FADD. Of genes located in the 11q13 amplicon, cortactin expression is the best predictor for shorter disease-specific survival in late stage laryngeal carcinomas.

Primary central nervous system lymphoma (PCNSL) is a rare disease. A small number of cytogenetic studies of PCNSL have been conducted and several reports have been published on associated molecular and protein expression data. We combined these approaches in a series of eight PCNSL cases, analyzing the chromosomal abnormalities using comparative genomic hybridization (CGH), testing for Epstein Barr virus (EBV) involvement by in situ hybridization for EBER, assessing expression of p53, Bcl-2, Bcl-6 and CD10 by means of immunohistochemistry, and screening for mutations of the TP53 gene by DGGE. TP53 gene mutations and EBV expression were not detected. Most of the cases showed p53, Bcl-6 and Bcl-2 protein expression. CGH revealed DNA copy number changes in all eight cases. The most frequent changes were gains of chromosome 12 (63%), chromosome 18 (50%) and 20q (38%), and loss of chromosome arm 6q (75%). No correlation between protein expression and chromosomal abnormalities was found in these eight cases. Although gains of chromosome 12, 18 and 20q and loss of 6q have also been reported in systemic diffuse large B-cell lymphomas, the frequency of 6q deletion is clearly higher in PCNSL. This creates a similarity to primary lymphomas of the testes that also frequently have deletions of 6q. This suggests that suppressor genes located on chromosome 6q may play a role in the development of lymphomas at immunoprivileged sites, like the CNS.

BACKGROUND. Multidrug resistance (MDR) is associated with expression of P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1), and lung resistance-related protein (LRP). Tumor necrosis factor (TNF-alpha) is able to modify the expression of these three proteins in different cell types. The effect of TNF-alpha in the clinical situation on patients with soft tissue sarcomas (STS) is indeterminate. METHODS, Thirty-seven patients with a locally advanced extremity STS underwent hyperthermic isolated limb perfusion (HILP) with TNF-alpha and melphalan; 15 patients received additional interferon gamma, Clinical and histologic responses were documented and used to define the overall response. Samples before and after HILP were analyzed immunohistochemically for P-gp! MRP1, and LRP, Samples were scored as negative or positive (less than or equal to 5% or > 5% positive tumor cells). RESULTS, Six patients had an overall complete response, 25 patients had a partial response, and 4 patients with STS revealed no change; in 2 patients, the response remained unclear. The percentage STS samples that were positive for all three proteins dropped from 92% before HILP to 85% after HILP. P-gp positive samples were encountered more often than MRP1 positive samples (P

PURPOSE: Several studies have reported clinical behavior and chemotherapy resistance in leiomyosarcomas, but these studies did not differentiate between soft tissue leiomyosarcomas (LMS) and malignant gastrointestinal stromal tumors (GIST). Multidrug resistance (MDR) has been associated with the expression of P-glycoprotein (P-gp), multidrug resistance protein (MRP1), and lung resistance protein (LRP). The aim of the present study was to compare LMS and GIST with respect to clinical outcome and MDR parameters. PATIENTS AND METHODS: Clinical outcome was evaluated in 29 patients with a primary deep-seated LMS and 26 patients with a primary malignant GIST. Paraffin-embedded material, available for 26 patients with LMS and 25 with GIST, was used for immunohistochemical detection of P-gp, MRP1, LRP, and c-kit. RESULTS: Mean overall survival (OS) was 72 months for LMS patients and 31 months for GIST patients (P < .05). Metastases occurred in 16 (59%) of 27 assessable LMS patients and in 10 (56%) of 18 assessable GIST patients. LMS predominantly metastasized to the lungs (14 of 16 patients), whereas GIST tended to spread to the liver (five of 10 patients) and the abdominal cavity (three of 10 patients; P < .001). P-gp and MRP1 expression was more pronounced in GIST than in LMS (P < .05): the mean percentage of P-gp expressing cells was 13.4% in patients with LMS and 38.4% in patients with GIST, and the mean percentage MRP1 expressing cells was 13.3% in patients with LMS and 35.4% in patients with GIST. LRP expression did not differ between LMS and GIST. c-kit was expressed in 5% of the LMS patients and in 68% of the GIST patients. CONCLUSION: LMS patients have a better survival than GIST patients, and the metastatic pattern is different. Expression of MDR proteins in LMS is less pronounced than in GIST.

Cytogenetic studies in small groups of patients with malignant peripheral-nerve-sheath tumors (MPNST) revealed complex karyotypes with no consistent changes. A computer-assisted cytogenetic analysis using a cytogenetic database was performed to determine recurrent cytogenetic alterations in 51 MPNSTs (44 from the literature and 7 new cases) and to allow direct cytogenetic comparison between NF-l-associated and sporadic MPNSTs. Significant loss (p

Purpose: To examine the prognostic value of three endogenous hypoxia markers (hypoxia inducible factor I a subunit [HIF1 alpha], carbonic anhydrase IX [CA-IX], and glucose transporter type 1 [GLUT-1]) on the clinical outcome in patients with early-stage glottic carcinoma primarily treated with radiotherapy (RT) and to determine the predictive hypoxic profile to choose the optimal treatment of early-stage laryngeal carcinoma.Methods and Materials: Immunohistochemistry for HIF1 alpha, CA-IX, and GLUT-1 was performed on formalin-fixed, paraffin-embedded, pretreatment tissue samples of 91 glottic squamous cell carcinoma specimens. The patient group consisted only of those with early-stage (T1-T2) glottic carcinoma, and all patients were treated with RT only. Relative tumor staining was scored on the tissue samples. Receiver operating curve analysis was performed to determine the optimal cutoff value for each tumor marker. Cox regression analyses for the variables HIF1 alpha, CA-IX, GLUT-1, gender, age, hemoglobin level, T category, N category, tobacco use, and alcohol use were performed with local control and overall survival as endpoints.Results: HIF1 alpha overexpression in early-stage glottic carcinoma correlated significantly with worse local control (hazard ratio [HR], 3.05; p = 0.021) and overall survival (HR, 2.92; p = 0.016). CA-IX overexpression correlated significantly with worse local control (HR, 2.93; p = 0.020). GLUT-1 overexpression did not show my correlation with the clinical outcome parameters. Tumors with a nonhypoxic profile (defined as low HIF1 alpha and low CA-IX expression) had significantly better local control (HR, 6.32; p = 0.013).Conclusion: The results of our study have shown that early-stage glottic laryngeal carcinomas with low HIF1 alpha and CA-IX expression are highly curable with RT. For this group, RT is a good treatment option. For tumors with HIF1 alpha or CA-IX overexpression, hypoxic modification before RT or primary surgical treatment should be considered. (C) 2008 Elsevier Inc.

Purpose: Amplification of the 11q13 region is a frequent event in human cancer. The highest incidence (36%) is found in head and neck squamous cell carcinomas. Recently, we reported that the amplicon size in 30 laryngeal and pharyngeal carcinomas with 11q13 amplification is determined by unique genomic structures, resulting in the amplification of a set of genes rather than a single gene.Experimental Design: To investigate which gene(s) drive the 11q13 amplicon, we determined the smallest region of overlap with amplification and the expression levels of all genes within this amplicon.Results: Using array-based comparative genomic hybridization analysis, we detected a region of ∼1.7 Mb containing 13 amplified genes in more than 25 of the 29 carcinomas. Quantitative reverse transcription-PCR revealed that overexpression of 8 potential driver genes including, cyclin D1, cortactin, and Fas-associated death domain (FADD), correlated significantly with DNA amplification. FADD protein levels correlated well with DNA amplification, implicating that FADD is also a candidate driver gene in the 11q13 amplicon. Analysis of 167 laryngeal carcinomas showed that increased expression of FADD (P = 0.007) and Ser194 phosphorylated FADD (P = 0.011) were associated with a worse disease-specific survival. FADD was recently reported to be involved in cell cycle regulation, and cancer cells expressing high levels of the Ser194 phosphorylated isoform of FADD proved to be more sensitive to Taxol-induced cell cycle arrest.Conclusion: Because of the frequent amplification of the 11q13 region and concomitant overexpression of FADD in head and neck squamous cell carcinomas, we hypothesize that FADD is a marker to select patients that might benefit from Taxol-based chemoradiotherapy.

Purpose: A small proportion of lung cancer patients have an inversion involving the ALK gene on chromosome 2. These ALK+ patients initially respond to crizotinib, but later develop progressive disease. This resistance can be due to gatekeeper mutations in the kinase domain of the ALK gene like L1196M and G1269A, copy number gain of the EML4-ALK fusion gene, and mutations in EGFR and KRAS. We aimed at identifying fusion genes that may explain the resistance mechanism in patients progressing on crizotinib. Materials and Methods: Frozen tissue of the resistant tumor samples was available for four EML4-ALK positive patients (Table 1). Paired end RNA sequencing was performed using the Illumina TruSeq RNA platform. DeFuse (v.0.6.1) was used to identify fusion products. Candidate fusion genes were validated by RT-PCR. In addition, we used the IGV browser to identify mutations in resistance-associated genes in the RNA-seq data. Results: Thirteen fusions genes were identified with high confidence (Table 1). In three of the four patients we detected an EML4-ALK fusion product. Four novel fusion products with a functional ORF were confirmed by RT-PCR. Three of these fusion products were present in patient 1 (Table 1). The fourth fusion involving CLIP4-VSNL1 was detected in patient 3. Interestingly, three of the 4 fusion products observed in patient 3 involved 5 genes that are all close to the ALK locus, i.e. EML4, ALK, CLIP4, VSNL1 and MCFD2 (Table 1). In addition, we found two resistance-related mutations in the tyrosine kinase domain of the ALK gene, i.e. p.C1156Y and p.G1269A, in patients 2 and 3, respectively. Fusion products in four crizotinib resistant lung cancer patientsPatientAgeSmokingALK immunohistochemistryTumor response (PFS in months)Fusion genesORF147CurrentNot availableNo (1.4)RAB35-ATP2A2YesSLC10A7-TTC29YesSTAB2-NUAK1YesKMT2B-AC002115.9NoPIAS1-SLC24A6NoZNF827-ARHGAP10No227None+Yes (9.2)EML4-ALKYesNRG1-RBPMSNo342None+Yes (10.4)EML4-ALKYesCLIP4-VSNL1YesMCFD2-CLIP4NoCPSF6-RBMS2No456Current+Yes (15.7)EML4-ALKYes Conclusion: We found four new fusion products with a functional ORF using RNA sequencing of crizotinib resistant tumor samples. Further analysis of the primary tumor samples is ongoing and will reveal if these fusion genes might have been induced by the crizotinib treatment. Two of the four patients have a known resistance-inducing mutation in the ALK gene. Citation Format: Ali Saber, Anthonie van der Wekken, Klaas Kok, Martijn M. Terpstra, Mirjam F. Mastik, Wim Timens, Ed M.D. Schuuring, T. Jeroen Hiltermann, Harry J.M. Groen, Anke van den Berg. Detection of fusion genes in lung cancer biopsies of crizotinib resistant patients. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4245. doi:10.1158/1538-7445.AM2015-4245

Purpose HPV-associated cancer in the head-neck region has been reported at high frequencies in certain countries and is considered a separate entity. Since the prevalence of HPV positivity in oropharyngeal squamous cell carcinomas is currently not known in the Northern part of the Netherlands, the aim was to analyze HPV prevalence in oropharyngeal tumours treated at our centre. Material and methods Based on the Dutch cancer registration, we collected clinical, pathological, and follow-up data and formalin-fixed paraffin embedded samples of a complete cohort of 125 tonsillar and base-of-tongue oropharyngeal tumours treated in our centre from 1997 to 2009. HPV testing was performed using an established algorithm of p16 immunohistochemistry, followed by HPV-PCR of the positive cases. HPV-BRISH was performed as extra control of p16 negative cases. Results p16 staining could be assessed on 109 cases. 32/109 (29%) were p16+ of these 32 cases 21/32 (66%) were HPV-GP+, 16 cases were found HPV16+ and one HPV18+, three were HPV33+ and one HPV35+. HPV-BRISH showed 83/102 (81%) negativity and 19/102 (19%) positivity. BRISH had a sensitivity of 85% and a specificity of 98%, as only two p16- cases were positive for BRISH. HPV prevalence increased from 11% between 1997 and 2002, to 27% between 2003 and 2009. Conclusions In the period 1997–2009, 19% of the tonsillar and base-of-tongue tumours in the Northern Netherlands was HPV+. This prevalence is lower than in other regions in the Netherlands (33%) and in Europe (40%). Remarkably, a large increase in prevalence was observed in the more recent years. The relative low incidence in our region might be due to the relative high percentage of smokers, associated with non-HPV related oropharyngeal tumours. Currently HPV testing of a series of 200 oral squamous cell carcinomas from our centre is in progress.

About halve of all oral squamous cell carcinoma (OSCC) patients have occult nodal metastases (N-status) due to the inaccuracy of current detection methods. The aim of our study is to find DNA methylation markers in the DNA of the primary tumor that predict N-status. For biomarker discovery we used a new approach combining a global DNA methylation screen, next generation sequencing, quantitative methylation detection and microarray expression profiling. Here we report the success of this new approach and the further validation of novel methylation markers. We assessed global methylation levels on DNA extracted from 6 oral squamous cell carcinomas (OSCC) with nodal metastases (N+) and 6 OSCC without nodal metastases (N0) by MethylCap-Seq. Isolated methylated DNA fragments were sequenced by Illumina GA II and computationally mapped back to the genome. A list was composed of the 5000 most differentially methylated genes between the N + and the N0 group. The most significantly differentially methylated genes were selected for further validation by Quantitative Methylation Specific PCR and Pyrosequencing on an independent series of 20 N + and 20 N0 OSCC. In addition the MethylCap-Seq methylation data was combined with microarray expression data of 696 genes for a N-status validation cohort containing 222 OSCC (Hoof et al., 2012, J. Clin. Oncol.). The effect of DNA methylation on gene expression will be measured by (Q)RT-PCR and immunohistochemistry on genes differently hypermethylated and downregulated. The most promising methylation markers will be further validated on a N-status validation cohort containing 463 cases for which complete clinicopathological and follow-up data are available. These markers might contribute to better diagnosis, improved quality of life and may be associated with increased survival.

Annually 650,000 new patients are diagnosed with Head and Neck cancer, making it the sixth most common cancer worldwide. The 5-year survival is only 60% due to inaccurate detection of nodal metastases in the cervical or submandibular region (N-status). Our goal is to find new DNA methylation markers in the primary tumor that predict nodal metastases to improve diagnostics and treatment. For biomarker discovery we used a new approach combining global methylation assessment, next generation sequencing, quantitative methylation and microarray expression profiling. Here we report the success of this new approach and the further validation of novel biomarkers. We performed MethylCap-Seq on DNA from 6 oral squamous cell carcinomas (OSCC) with nodal metastases (N+) and 6 OSCC without nodal metastases (N0) to measure global methylation levels. After comparison of the sequenced reads a list was composed of the 5000 most differentially methylated genes between the two groups. The most significantly differentially methylated genes were validated using Quantitative Methylation Specific PCR (QMSP) and Pyrosequencing on a independent series of 20 N+ and 20 N0 OSCC. In addition, the MethylCap-Seq methylation data was combined with microarray expression data of 696 genes for a N-status validation cohort containing 222 OSCC (Hoof et al.; J Clin Oncol. 2012 Oct 8). Based upon the assumption that hypermethylation is associated with downregulation of gene expression, we selected hypermethylated and downregulated genes distinguishing between the two groups. The effect of DNA methylation on gene expression will be measured by (Q)RT-PCR and immunohistochemistry on a N-status validation panel. The most promising methylation markers will be further validated by Pyrosequencing and QMSP on DNA of a N-status validation cohort containing 463 cases for which complete clinicopathological and follow-up data are available. These markers might contribute to better diagnosis, improved quality of life and may be associated with increased survival. This research was supported by the Center for Translational Molecular Medicine (project AIRFORCE). Citation Format: Martijn Clausen, Lieuwe J. Melchers, Leonie Bruine de Bruin, Mirjam F. Mastik, Lorian Slagter-Menkema, Harry J. Groen, Bert van der Vegt, Bernard F. Van der Laan, Tim De Meyer, Wim Van Criekinge, G Bea Wisman, Jan L. Roodenburg, Ed Schuuring. DNA methylation marker discovery for the prediction of nodal metastases in head and neck cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 645. doi:10.1158/1538-7445.AM2013-645