Squamous Cell Carcinoma Of The Head And Neck Specimens Research Articles

NLRP3 inflammasome activation promotes inflammation-induced carcinogenesis in head and neck squamous cell carcinoma

BackgroundNLRP3 inflammasome acts as a danger signal sensor that triggers and coordinates the inflammatory response. However, the roles of NLRP3 inflammasome in the tumorigenesis and development of cancer stem cells (CSCs) of squamous cell carcinoma of the head and neck (SCCHN) remain ambiguous.MethodsIn our study, tissue microarrays, ELISA, sphere-forming assay, colony formation assay and Western blot analysis were performed to evaluate the effect of NLRP3 inflammasome on the development of CSCs in human SCCHN tissue specimen, cell lines, and transgenic mouse SCCHN model.ResultsThe components of NLRP3 inflammasome, namely, NLRP3, ASC, Caspase-1, and IL-18 were correlated with CSCs markers BMI1, ALDH1 and CD44 in human SCCHN specimens. Moreover, NLRP3, Caspase-1, IL-1β, and IL-18 were highly expressed in SCCHN cell lines. NLRP3 inflammasome activated by LPS and ATP promoted sphere-forming and colony formation capacities along with an upregulation of BMI1, ALDH1 and CD44. In addition, NLRP3 inflammasome blockade by NLRP3 inhibitor MCC950 reduced sphere and colony number, also decreased the expression of BMI1, ALDH1 and CD44 in SCCHN cell lines. Expression of NLRP3, ASC, Caspase-1, IL-1β, IL-18, BMI1, ALDH1 and CD44 was upregulated in Tgfbr1/Pten 2cKO mouse SCCHN model, and NLRP3 inflammasome expression was closely related to those CSCs makers in mice SCCHN. However, MCC950 treatment reduced the expression of NLRP3 inflammasome, CSCs markers BMI1, ALDH1 and CD44 in Tgfbr1/Pten 2cKO mice SCCHN. In addition, blockade of NLRP3 inflammasome can also delayed the tumor-burdened speed in SCCHN mice.ConclusionsOur study demonstrates that NLRP3 inflammasome was upregulated and associated with the carcinogenesis and CSCs self-renewal activation in SCCHN. NLRP3 inflammasome can be a potential target in the development of novel approaches for head and neck squamous cell carcinoma therapy.

1059P - PD-L1 Detection and Assay Performance in Squamous Cell Carcinoma of the Head and Neck Using PD-L1 IHC 28-8 pharmDx

Background: Detecting PD-L1 protein expression by immunohistochemistry has shown to be effective in identifying patients who may benefit from treatment with PD-1 targeted immune checkpoint inhibitors. The PD-L1 IHC 28-8 pharmDx assay has been applied in formalin-fixed, paraffin-embedded (FFPE) squamous cell carcinoma of the head and neck (SCCHN) tissues for measuring PD-L1 expression and its associated treatment effect with nivolumab. Assay performance results of PD-L1 IHC 28-8 pharmDx in SCCHN, including validation in external reproducibility, are described. Methods: Antigen retrieval was conducted on Dako PT Link and automated staining was performed with Autostainer Link 48 platform using the PD-L1 IHC 28-8 pharmDx protocol, per instructions for use. The PD-L1 staining was assessed by tumor proportion score to report the percentage of PD-L1 expression in invasive SCCHN. Assay performance was validated at the ≥ 1% expression level on commercially procured FFPE SCCHN specimens. Results: PD-L1 expression was measured on 236 unique specimens originating from squamous cell carcinoma of the tongue, tonsil, nasopharynx, oropharynx, hypopharynx, and larynx. The assay demonstrated acceptable sensitivity and reported a large range of PD-L1 expression from 0 to 95% positive tumor cells and 0 to 3+ staining intensity. Acceptable correlation was observed between primary and metastatic specimens and between “sister” blocks from the same patient. Validation of assay precision and robustness (to target retrieval solution pH, target retrieval solution temperature, target retrieval time, and cut section thickness) demonstrated agreement estimates above 97.5% with the lower bound of two-sided 95 percent confidence intervals at 95% or higher. When tested in external sites, intra- and inter-site reproducibility, and intra- and inter-observer agreements were estimated above 94% with the lower bound of two-sided 95 percent confidence intervals at 88% or higher. Stability of PD-L1 staining in aged cut sections demonstrated interim stability at 4 months with ongoing evaluation. Conclusions: PD-L1 IHC 28-8 pharmDx has shown to be reproducible and robust in detecting PD-L1 expression in FFPE human SCCHN specimens using the Autostainer Link 48. Legal entity responsible for the study: Agilent Technologies, Inc. Funding: Agilent Technologies, Inc. and Bristol Myers Squibb Disclosure: S. Alvarez: Currently employed by a for-profit health care company, Agilent Technologies. Own stock in a for-profit health care company, Agilent Technologies. J. Chan, C. Felten: Employed, leader for, and has ownership in Gemini Diagnostics. Paid consultant for Agilent Technologies. J. William: Employed by a diagnostic laboratory, Neogenomics. Was in a paid consulting role for Agilent Technologies in the last 2 years. D.A. Hanks: Employed and holds leadership for Premier Pathology Laboratories, Inc. Employed by Agilent Technologies, Inc. Holds intellectual property relating to health and medicine in the last 2 years while working with Agilent Technologies. A. Northrup: Employed by Agilent Technologies and owns stock in Agilent technologies. Has been reimbursed for travel, accommodations, or other expenses by Agilent Technologies in the last 2 years. D. Jaiswal, M. Jansson, T. Phillips: Employed by Agilent technologies. And own stock in Agilent Technologies. A. Segal: Was employed by Agilent Technologies and owns stock in Agilent Technologies. I. Satnick, H. Little, B. Wynne, C. Pierce: Employed by Agilent Technologies. H. McDonald: Employed by Agilent Technologies. Was employed by Baster/Baxalta/Shire in the last two years. Owns stock in Shire, Inc. J. Carnahan: Employed by Agilent Technologies. Was employed by Agensys in the past 2 years and received research funding and paid travel expenses from Agensys. Owns stock in Amgen. S.Y. Reddy: Employed by Agilent and owns stock in Agilent Technologies. H.D. Inzunza: Was employed by Bristol-Myers Squibb and is employed by Halozyme. E. Oroudjev: Employed by Agilent Technologies. Is in leadership role for Agilent Technologies. Owns stock in Agilent Technologies.

Assay performance of the PD-L1 IHC 28-8 pharmDx assay in squamous cell carcinoma of the head and neck (SCCHN).

e14588 Background: The PD-L1 IHC 28-8 pharmDx assay has been developed for use in detection of PD-L1 protein in formalin-fixed, paraffin-embedded (FFPE) non-squamous NSCLC and melanoma tissues for associated treatment effect with nivolumab. Validation of the assay for measuring PD-L1 expression level in human squamous cell carcinoma of the head and neck (SCCHN) FFPE sections has been conducted and results are described. Methods: Visualization of the PD-L1 IHC 28-8 pharmDx assay is based on the EnVision FLEX IHC technology. As described in the Instructions For Use, antigen retrieval was performed using the Dako PT Link, and the automated staining was conducted with Autostainer Link 48. The assay performance was validated on commercially procured FFPE SCCHN specimens. Results: Assessment of assay sensitivity to PD-L1 expression was measured on 236 unique specimens originating from squamous cell carcinoma of the tongue, tonsil, nasopharynx, oropharynx, hypopharynx, and larynx. The study demonstrated PD-L1 positive staining across a range of 0-95% positive tumor cells and 0 to 3+ staining intensity. Among these tested specimens, 44% of specimens had PD-L1 expression levels ≥1%. Assay robustness was validated by assessing critical parameters such as target retrieval solution pH, target retrieval solution temperature, target retrieval time, and cut section thickness. Assay reproducibility was evaluated in a study at three external sites. Reproducibility of intra-site, inter-day, and inter-site agreement was assessed in addition to inter- and intra-observer agreement. Assay robustness and reproducibility demonstrated agreement estimates above 85% with values for lower bound 95% confidence intervals calculated above 85%. Conclusions: These studies demonstrate that the PD-L1 IHC 28-8 pharmDx assay is reproducible and robust when used for automated detection of PD-L1 protein in FFPE human SCCHN specimens using Autostainer Link 48.

Association between phosphorylated AMP-activated protein kinase and acetyl-CoA carboxylase expression and outcome in patients with squamous cell carcinoma of the head and neck.

BackgroundEpidemiological studies have indicated that impaired glucose metabolism may increase the risk of squamous cell carcinoma of the head and neck (SCCHN). AMP-activated protein kinase (AMPK) regulates glucose and lipid metabolism via the phosphorylation and subsequent inactivation of its downstream target acetyl-CoA carboxylase (ACC).Thus, we analyzed the expression of pAMPK and its downstream target phosphorylated acetyl-CoA carboxylase (pACC), as well as their impact on the survival of patients with resected SCCHN.MethodsOne hundred eighteen patients with surgically resected SCCHN were enrolled. Immunohistochemical (IHC) staining for pAMPK and pACC was performed using tissue microarrays of operative specimens of SCCHN. The expression was divided into two or three groups according to the IHC score [pAMPK: negative (0), positive (1–3); pACC: negative (0), low expression (1, 2), and high expression (3)]. Statistical analysis was performed to determine the association of pAMPK expression with clinicopathological features and pACC and pErk expression.ResultsThe positive rates of pAMPK and pACC expression were 64.4% (76/118) and 68.6% (81/118), respectively. pAMPK was significantly higher in patients aged younger than 60 years (P = 0.024; χ2test) and those with early-stage (T1/T2; P = 0.02; χ2 test) and oral cavity (P = 0.026; Fisher’s exact test) tumors. In multivariate analysis, pAMPK expression was not significantly correlated with overall survival (OS) (adjusted hazard ratio [HR]: 0.66; 95% confidence interval [CI]: 0.35–1.23), whereas high pACC expression was independently associated with worse OS in node-positive patients (adjusted HR: 17.58; 95% CI: 3.50–88.18).ConclusionsStrong expression of pACC was found to be an independent prognostic marker for patients with node-positive SCCHN. Our results suggest that pACC may play a role in tumor progression of SCCHN and may help to identify patient subgroups at high risk for poor disease outcome.

Acetylated Tubulin (AT) as a Prognostic Marker in Squamous Cell Carcinoma of the Head and Neck

Acetylated tubulin (AT) expression has been proposed as a marker for sensitivity to taxane chemotherapy. We wanted to explore AT as a prognostic marker in squamous cell carcinoma of the head and neck (SCCHN). We assessed AT expression in archival tissue from our institutional tissue bank of primary SCCHN specimens. We also examined AT expression on pre-therapy tissues of patients with SCCHN receiving induction chemotherapy with docetaxel, cisplatin and 5FU (TPF IC). AT expression was assessed on archival cases of SCCHN with (N = 63) and without (N = 82) locoregional lymph node metastases (LNM). The predominant tumor site was oral cavity (52 %). Immunohistochemistry staining was based on staining intensity and percentage of tumor cells stained to create a weighted index (WI). A total of nine patients who received TPF IC were evaluable for response by RECIST and also had pre-therapy tissues available. A significant independent correlation between AT and tumor grade (p = 0.001) and primary location (p = 0.008) was noted. There was a trend of higher AT in patients with presence of LNM (p = 0.052) and a trend in improved OS for patients with an AT WI below the median compared to those above the median for patients with no LNM (p = 0.054). For patients treated with induction TPF, we observed an inverse correlation between AT expression and response to TPF IC (p = 0.0071). AT expression is correlated with tumor grade and primary site. There was an observed trend correlating AT with presence nodal metastases. The observed inverse correlation with response to taxane based chemotherapy needs validation in a larger sample size.

Abstract 554: Qualification of a p16INK4A immunohistochemistry (IHC) assay for determination of HPV status in archival Squamous Cell Carcinoma of the Head and Neck (SCCHN) formalin fixed paraffin embedded (FFPE) specimens from a randomized phase 3 trial

Abstract Introduction: HPV positive SCCHN has a distinct set of molecular alterations and a better prognosis in the locally advanced setting. When HPV is integrated into the host cell genome, HPV protein E7 degrades host retinoblastoma protein, an inhibitor of p16INK4A transcription. Thus, in persistent HPV gene expressing tumors, elevated p16INK4A RNA and protein levels serve as a surrogate of HPV infection applicable to FFPE archival tumor specimens. Our aim was to qualify an existing IHC assay for reliable detection of active HPV expression in SCCHN archival FFPE tumor samples from a randomized phase 3 trial in the recurrent/metastatic (R/M) treatment setting. Methods: The CINtec™ p16INK4A Histology Kit is a semi quantitative, immunocytochemical assay for the evaluation of p16INK4A protein expression in FFPE sections. Banked SCCHN specimens were examined for p16INK4A expression to establish repeatability, reproducibility, and long term analyte stability (blocks and slides). Comparative studies were performed with a p16INK4A reverse transcription quantitative polymerase chain reaction (RT qPCR) assay and an HPV in situ hybridization assay to examine intra assay concordance. Results: 101 banked SCCHN FFPE tumor specimens were utilized for the qualification study. 42 of 101 (42%) SCCHN specimens (all sites) and 17 of 41 (41%) oropharyngeal specimens were HPV positive by p16INK4A. Five slides from each of 6 SCCHN specimens ranging in the percentage of cells expressing p16INK4A (positive, low positive, and negative) were tested on a single day to demonstrate inter assay repeatability. Serial sections from 6 tumors were tested on 3 consecutive working days using multiple automated staining instruments run by different technicians to determine intra assay reproducibility. Inter pathologist scoring, blinded to run, was demonstrably consistent. Positive p16INK4A staining was demonstrated in blocks stored up to 19 years. Analyte stability was demonstrated in cut sections prepared 27 months in advance. Comparative assay studies yielded consistent, though not identical, results. These results led to the design and implementation of a detailed imaging scoring guideline. Conclusions: The CINtecTM p16INK4A Histology Kit was qualified for use as a surrogate for HPV infection in SCCHN specimens. This assay was then utilized to test banked specimens from a randomized, phase 3 study of the anti EGFR antibody panitumumab in patients with HPV positive R/M SCCHN tumors. In this study, patients with HPV positive tumors did not benefit from the addition panitumumab to a platinum + 5 fluorouracil chemotherapy regimen whereas there was a significant improvement in overall survival in the HPV negative group (Vermorken et al., European Multidisciplinary Cancer Congress 2011). Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 554. doi:1538-7445.AM2012-554

Effects of epidermal growth factor receptor and insulin‐like growth factor 1 receptor inhibition on proliferation and intracellular signaling in cutaneous SCCHN: Potential for dual inhibition as a therapeutic modality

Combined inhibition of epidermal growth factor receptor (EGFR) and insulin-like growth factor-1 receptor (IGF-1R) has been proposed as a therapy for cutaneous squamous cell carcinoma of the head and neck (SCCHN). Receptor expression and downstream signaling were assessed in cutaneous squamous cell carcinoma (SCC) cell lines and patient samples. EGFR and IGF-1R signaling was inhibited in cutaneous SCC cell lines using erlotinib and/or picropodophyllin. EGFR and IGF-1R were overexpressed in cutaneous SCCHN specimens relative to normal skin. Dual inhibition of both receptors prevented cell growth and decreased activation of Akt and p42/44 mitogen-activated protein kinase (MAPK) more effectively than either inhibitor alone. Dual inhibition of EGFR and IGF-1R is effective at blocking cell growth, and is correlated with inhibition of Akt and p42/44 MAPK, suggesting that this may be a promising treatment for cutaneous SCCHN.

Correlation of NF-κB signal pathway with tumor metastasis of human head and neck squamous cell carcinoma

BackgroundNuclear factor-kappa B (NF-κB) signaling constitutes a key event in the multistep process of carcinogenesis, progression and treatment in many cancer types. However, the significance of NF-κB pathway for complex and tissue-specific aspects of head and neck cancer progression, such as invasion and metastasis, is less understood.MethodsThe expression of NF-κB p65 in squamous cell carcinoma of the head and neck (SCCHN) clinical specimens by immunohistochemistry. The role of NF-κB activity in head and neck squamous cell carcinoma was determined by western blot, reporter assay and EMSA analysis in vitro and metastasis assays in vivo in different metastatic potential tumor cells. Furthermore, the apoptosis rate and expression of metastasis-related protein such as MMP9 and VEGF were examined by Annexin V/PI staining and Western blot, respectively.ResultsA higher level of active nuclear-localized NF-κB was observed in the metastatic SCCHN specimens group (p < 0.01). The NF-κB activities of SCCHN cell lines with different metastatic potentials were then determined and in excellent agreement with results found in SCCHN specimens, highly metastatic SCCHN cell lines expressed high level of NF-κB activity. The treatment of highly metastatic SCCHN cells with NF-κB inhibitors reduced the in vitro cell invasion capacity of the cells without affecting the apoptotic rate. Additionally, the NF-κB inhibitors significantly inhibited the experimental lung metastasis of Tb cells and lymph node metastasis of TL cells in nude mice. Furthermore, the expression of metastasis-related proteins, such as matrix metalloproteinase 9 and vascular endothelial growth factor, was inhibited by pyrrolidine dithiocarbonate.ConclusionsThis study suggests that NF-κB activity significantly contributes to tumor hematologic and lymphatic metastases and may aid in the development of early detection methods or therapies targeting non-conventional molecular targets.

Abstract A126: Analysis of excision repair cross complementing group 1 (ERCC1) expression in squamous cell carcinoma of the head and neck (SCCHN)

Abstract Introduction: ERCC1 is a key enzyme in the nucleotide excision repair pathway and increased expression of ERCC1 is associated with cisplatin resistance in some cancers. Given the widespread use of platinum therapy for the treatment of SCCHN, we characterized the range of ERCC1 expression in SCCHN specimens using an immunofluorescence-based assay (automated quantitative analysis-tissue microarray [AQUA-TMA]). There is currently inadequate data regarding the range of ERCC1 expression in SCCHN, and how ERCC1 levels correlates with treatment outcomes, ERCC1 has been studied in SCCHN by standard immunohistochemistry, however, this method is limited by variability of techniques and subjectivity of interpretation, Therefore, there is a need for a highly quantitative technique which can be accomplished on formalin fixed paraffin embedded tissue and small samples, Our goal is to develop a reproducible assay that can eventually be incorporated into standard patient care practice. Methods: Tissue microarrays containing head and neck squamous cell carcinoma samples obtained from patients treated at Fox Chase Cancer Center from 1999–2006 were constructed. Slides were stained by a modified indirect immunofluorescence method. Sections were incubated with ERCC1 antibody (8F1, Lab Vision) and wide-spectrum screening rabbit cytokeratin antibody (Dako Z0622). Prolong Gold mounting medium (P36931; Molecular Probes) containing 4,6-Diamidino-2-phenylindole (DAPI) was used to define tissue nuclei. A binary image (tumor mask) was created from the cytokeratin image of each histospot. ERCC1 levels were measured using fluorescent immunohistochemistry on the HistoRx PM-2000 image analysis platform and the data analyzed using AQUA algorithms. The in situ biomarker profiling system generated quantitative measurements of patient protein levels based on AQUA scores derived from fluorescent output of labeled markers. Both nuclear and non-nuclear (i.e., non-membrane/cytoplasmic) ERCC1 expression was measured Results: 41 SCCHN specimens (24 oral cavity, 7 oropharynx, 5 glottic tumors, 3 unknown primary, 2 other) were analyzed. There were 25 males and 16 females and age at diagnosis ranged from 25 to 80 years (mean 64). The majority of patients were treated primarily by surgery. The range of AQUA scores was 33.66 to 1696.39 (mean 501.78, stnd deviation 284). The 25th percentile was 337.35, and the 75th percentile was 639.37. ERCC1 was predominantly nuclear (i.e., non-membrane/cytoplasmic) in the SCCHN tissue samples. Conclusions: 1) It is feasible to determine a quantitative value of ERCC1 expression with AQUA. 2) There is a wide range of ERCC1 expression in SCCHN. 3) ERCC1 is predominantly localized to the nuclear compartment. 4) Ongoing work is being done to correlate ERCC1 levels with clinical features, sensitivity to platinum therapy, and survival. Citation Information: Mol Cancer Ther 2009;8(12 Suppl):A126.

Expression of a novel marker, Ubc9, in squamous cell carcinoma of the head and neck

Ubiquitin-conjugating enzyme (Ubc9) is a novel enzyme involved in posttranslational modification of cellular proteins. The objective of this study was to determine the expression of Ubc9 in squamous cell carcinoma of the head and neck (SCCHN). SCCHN specimens were stained with anti-Ubc9 antibodies, scored using a semiquantitative method, and statistically analyzed. Forty-six tumors were stained, 26 of which included adjacent mucosa. Ubc9 was significantly upregulated in the malignant and peritumoral tissues compared with mucosa from normal individuals. In peritumoral tissues, Ubc9 expression was detected in the basal and suprabasal epithelial layers. No Ubc9 was detected in epithelial cells in normal mucosa. These differences in Ubc9 expression were statistically significant (p < .0001). Tumor Ubc9 expression significantly correlated with clinical and pathologic stage. Ubc9 is significantly overexpressed in the primary SCCHN tumors and peritumoral mucosa compared with normal epithelial cells. These findings suggest that Ubc9 may play an important role in tumorigenesis and tumor progression of SCCHN.

Distinctive E‐cadherin and epidermal growth factor receptor expression in metastatic and nonmetastatic head and neck squamous cell carcinoma

The authors investigated whether coexpression and localization of E-cadherin (E-cad) and epidermal growth factor receptor (EGFR) had predictive and/or prognostic correlations with lymph node metastasis and/or survival in patients with squamous cell carcinoma of the head and neck (SCCHN). Immunohistochemistry (IHC) of archival tissue was performed to measure expression of EGFR and E-cad in surgical specimens of SCCHN (n = 143) that included primary tumors (PTs) with positive lymph nodes (Tu+Met) and their paired lymph node metastases (LnMet), PTs with negative lymph nodes (Tu(-Met)), and benign tissue biopsies as normal controls. IHC staining was quantified as a weighted index and as the ratio of membrane to cytoplasmic staining. Correlative expression between EGFR and E-cad also was examined in SCCHN cell lines by immunoblotting and immunofluorescence analyses. Three distinct expression patterns of EGFR and E-cad were observed. Membrane localization of E-cad was significantly lower in the Tu+Met group than in the Tu(-Met) group (P = .01) and was associated inversely with lymph node status (P = .009). Wilcoxon analysis of the combined markers demonstrated that expression and/or membrane localization of EGFR and E-cad were correlated with disease-free survival and overall survival in patients with SCCHN. The study of SCCHN cell lines demonstrated that cells with positive but low EGFR expression and with negative E-cad expression were relatively resistant to the EGFR tyrosine kinase inhibitor erlotinib. The current study suggested that examining not only the expression but also the localization of EGFR and E-cad simultaneously may have clinical relevance in predicting lymph node metastasis, patient survival, and response to EGFR-targeted therapy in patients with SCCHN.

Effects of the Integrin-Linked Kinase Inhibitor QLT0267 on Squamous Cell Carcinoma of the Head and Neck

To study the expression of integrin-linked kinase (ILK) in human squamous cell carcinoma of the head and neck (SCCHN) tumor specimens and cell lines and the efficacy of the novel small molecule QLT0267. Immunohistochemical analysis of 17 SCCHN tumor tissue specimens and 3 normal tongue tissue specimens for ILK expression and in vitro analysis of the effectiveness of QLT0267 on SCCHN cells. Academic medical center. Expression levels of ILK in SCCHN tumor specimens and cell lines and the efficacy of QLT0267 in inhibiting cell growth and inducing apoptosis in SCCHN cell lines. Most SCCHN tumor specimens stained for ILK, whereas none of the 3 normal tongue tissue specimens stained for ILK. Integrin-linked kinase was expressed in all 6 SCCHN cell lines tested. In 4 pairs of normal and SCCHN tumor specimens, ILK expression and activity were higher in most tumor samples tested. A kinase assay showed that QLT0267 inhibited the ILK activity of 2 SCCHN cell lines (TU167 and MDA1986). Modified tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, DNA fragmentation ladder, and TUNEL (terminal deoxynucleotidyl transferase-mediated biotin-deoxyuridine triphosphate nick-end()labeling) assays showed that QLT0267 inhibited cell growth and induced apoptosis in these 2 cell lines. A dose-dependent decrease in Akt phosphorylation was observed for these 2 cell lines on treatment with QLT0267. Integrin-linked kinase is overexpressed in SCCHN tumor specimens. Targeting ILK with the small-molecule ILK inhibitor QLT0267 inhibits cell growth and induces apoptosis in SCCHN cell lines by reducing ILK activity and Akt phosphorylation. Integrin-linked kinase may be an attractive target for molecular therapy with which to enhance treatment of SCCHN.

P16 gene alterations in locally advanced squamous cell carcinoma of the head and neck

We previously documented the presence of mutations/deletions in the tumor suppressor gene p16 in squamous cell carcinoma of the head and neck (SCCHN). However, the association of these p16 alterations with clinical outcome is unknown. In this study, RNA was isolated from 19 frozen SCCHN from 19 patients who were previously enrolled in the OSU intensification regimen 2. Quantitative real-time RT-PCR and direct sequencing analysis was then performed on the specimens to detect p16 gene alterations. Clinical outcome for each patient was updated and correlated with the p16 alterations found. Five tumor specimens were found to have no or very low expression of p16 when compared with normal tissue. The remaining 14 tumor samples demonstrated overexpression of p16 relative to the level of expression in normal tissue. Sequence analysis of the p16 RT-PCR product from these specimens allowed identification of mutational changes in the coding sequence of p16 in four of the SCCHN specimens. Subsequent analysis of clinical outcome associated with locoregional/distant failure demonstrated no correlation with either altered expression of p16 or mutational status of p16. Results from this study indicate that p16 alterations are frequently found in this cohort of SCCHN. However, p16 alterations alone do not appear to be associated with clinical outcome.

Epstein-Barr virus detected in a head and neck squamous cell carcinoma cell line derived from an immunocompromised patient.

DNA tumor viruses potentially play a role in the development of squamous cell carcinoma of the head and neck (SCCHN). Human papillomavirus is found in up to 50% of SCCHN specimens, and Epstein-Barr virus (EBV) has been detected in nasopharyngeal carcinoma, Burkitt lymphoma, and other lymphomas. However, the role of EBV in nonnasopharyngeal SCCHN has not been thoroughly investigated. Twenty-one SCCHN cell lines derived from tumors of various subsites were used to screen for EBV DNA as well as latent viral protein expression. The method of EBV DNA detection was polymerase chain reaction with 3 independent primer sets from distinct regions of the genome. Expression of the viral protein EBNA-1, critical for the maintenance of the viral episome, was monitored by immunofluorescence using an antibody specific for EBNA-1. In addition, 12 paraffin-embedded tumor specimens and adjacent normal tissues were analyzed by polymerase chain reaction. These tumor specimens were further characterized by immunohistochemistry with the use of a mouse monoclonal antibody that recognizes EBNA-1. Little or no EBV DNA was detected in 20 of 21 cell lines or in any of the tumor specimens, while detecting approximately 40 genome copies in a control reaction. Accordingly, these cell lines and specimens were negative for EBNA-1 expression. In 1 cell line derived from an immunosuppressed patient, EBV DNA was detected, and on further examination a small percentage of cells expressed EBNA-1 as shown by immunofluorescence. Although EBV may not be a major cofactor contributing to the proliferation of SCCHN, the limited initial evidence suggests that EBV may be involved in development of SCCHN in immunosuppressed patients.

Fluorescence in situ hybridization for detecting TP16MTS1/CDK41 gene deletions in squamous cell carcinoma of the head and neck

We have previously shown TP16 MTS1/CDK41 gene deletion in more than 50% of a cohort of squamous cell carcinoma of the head and neck (SCCHN) patients using polymerase chain reaction (PCR). We have performed fluorescence in situ hybridization (FISH) on paraffin-embedded SCCHN specimens from the same cohort to identify the deletion of TP16 MTS1/CDK41CDK41 gene. Twenty normal and 19 SCCHN specimens were studied. An α-satellite DNA probe specific for chromosome 9 and a cosmid probe for the TP16 MTS1/CDK41CDK41 gene were used. Of the 19 tumors examined by FISH, 6 had homozygous deletions, 7 were hemizygously deleted, and the remaining 6 showed no evidence of deletion of the TP16 MTS1/CDK41 gene. None of the normal specimens showed TP16 gene deletion. Data obtained from FISH highly correlated with the PCR results for the identification of TP16 MTS1/CDK41 gene deletions. Patients with deletion of the TP16 MTS1/CDK41 gene show a greater tendency toward the development of recurrence and metastasis.

Allelic imbalance at the DNA mismatch repair loci, hMSH2, hMLH1, hPMS1, hPMS2 and hMSH3, in squamous cell carcinoma of the head and neck

Background: Squamous cell carcinoma of the head and neck (SCCHN) is one of the 10 most frequently occurring cancers in the world. Defective mismatch repair, as exhibited by the phenomenon of microsatellite instability, has been observed in SCCHN although no reports of mismatch repair gene mutations or altered protein expression have been published. In a variety of microsatellite instability (MSI) positive cancers where mutations in the mismatch repair (MMR) genes were not observed, allelic imbalance at the loci of the MMR genes was prevalent. Objective: To investigate whether allelic imbalance at the MMR genetic loci contributes to the development of SCCHN. Materials and Methods: 35 matched normal/tumour SCCHN pairs were studied using 29 microsatellite markers located within and adjacent to six known DNA mismatch repair genes. In addition, mutational analysis and protein expression of hMSH2 and hMLH1 were investigated. Results and conclusions: We demonstrated that 36 and 17% of the analysed SCCHN specimens exhibited allele imbalance at the hMLH1 and hMSH3 genetic loci, respectively. Allelic instability at these two loci was found to be correlated with the MSI status of the SCCHN tumours. Allelic instability was found to be uncommon at the other MMR gene loci analysed. One mutation was found in hMSH2 and none in hMLH1 in this series of tumours. 23 of 24 (96%) of the examined SCCHN tumours showed reduced expression of either hMSH2 or hMCH1 genes. Allelic instability in the MMR genes, hMLH1 and hMSH3, is proposed to be involved in the aetiology of SCCHN tumours.

Human papillomavirus and p53 mutational status as prognostic factors in head and neck carcinoma.

Mutations of the p53 tumor-suppressor gene are common in squamous cell carcinoma of the head and neck (SCCHN) and may portend a worse prognosis. Human papillomavirus (HPV) represents another potential prognostic factor for SCCHN. The oncogenic potential of HPV may be due to the ability of its E6 oncoprotein to promote degradation of wild-type p53 protein. We wish to determine whether there is a lower incidence of p53 mutations in HPV-positive versus HPV-negative tumors, and if HPV and/or p53 status has an impact on survival. Thirty-two SCCHN specimens were analyzed for mutations of the p53 gene using single-strand conformational polymorphism (SSCP) analysis followed by DNA sequencing. The HPV status of all specimens was evaluated by use of polymerase chain reaction with HPV consensus primers and Southern blot hybridization. Pertinent clinical information was obtained from chart review. Nonsilent p53 mutations were present in 2 of 15 (13%) of HPV-positive tumors compared with 6 of 17 (35%) of HPV-negative tumors (p =.229; Fisher's exact test, odds ratio.28). A survival advantage was found between HPV-positive compared with HPV-negative specimens (p =.0264) and between p53 wild type compared with p53 mutant specimens (p =.01) by univariate log rank analysis. When stratified according to both HPV and p53 status, a statistically significant survival difference was observed largely because of a 100% survival for the HPV-positive/p53 wild-type group (p =.003). This preliminary study supports the notion that the presence of HPV confers a survival advantage among HNSCC patients, particularly when p53 is wild type.

Mutational status of overexpressed p16 in head and neck cancer: evidence for germline mutation of p16/p14ARF.

Inactivation of the p16 tumor suppressor gene is a common phenomenon in squamous cell carcinoma of the head and neck (SCCHN). Less commonly described is the observation of p16 overexpression in SCCHN. Since overexpression of p16 is a potent predictor of outcome in other cancers, we were interested in determining the level of expression of p16 in our SCCHN specimens as a prerequisite to later prognostic studies. We were also interested in determining the mutational status of p16 in these tumors, in order to determine whether the combination of overexpression and gene alteration may predict a different clinical outcome from overexpression alone. A total of 84 specimens of SCCHN were selected for study. These specimens were obtained from all major sites within the oral cavity, oropharynx, pharynx and larynx. The level of expression of p16 in SCCHN specimens was measured by semi-quantitative RT-PCR. In 35 cases, RNA was also isolated from matched normal tissue obtained from a negative tumor margin. In the other 49 cases, the expression level was compared with the level of expression measured in pooled normal RNA obtained from 10 specimens of normal epithelial tissue. Overexpression of p16 was documented when the level of expression in the tumor specimen was 2-fold or greater above the level of expression found in normal tissue. A total of 46 specimens demonstrated overexpression of p16 (55%). All specimens demonstrating overexpression were then subject to sequence analysis. Thirty specimens (65%) showed p16-specific gene alterations, ranging from intragenic deletions to single point mutations, and 15 of these cases concomitantly affect p14ARF. A single specimen demonstrated a silent point mutation within the p16 reading frame. This mutation produces a stop codon at residue 85 in the context of the p14ARF reading frame, predicting premature termination of p14ARF within a previously determined nucleolar localization signal. This observation suggests that in some cases at least, p14ARF may be a selective target for alteration, independently of p16. Analysis of a normal tissue specimen obtained from a negative tumor margin, and a blood sample obtained approximately five years after surgery indicate that this p14ARF-specific alteration may represent a germline mutation.

Serum level and tissue expression of c-erbB-1 and c-erbB-2 proto-oncogene products in patients with squamous cell carcinoma of the head and neck.

The proto-oncogene products erbB-l (EGF-Receptor) and erbB-2 (HER-2/neu), distinct members of the epidermal growth factor receptor family, are frequently overexpressed in squamous cell carcinoma of the head and neck (SCCHN). The accumulation of these transmembrane proteins may lead to significant amounts of the respective extracellular receptor domains (ECD) that are shed from the tumour cell surface and enter blood circulation, thus representing potential serum tumour markers. For erbB-l and erbB-2, we determined the ECD serum levels with enzyme-linked immunosorbent assays and evaluated the protein expression in tumour tissue by immunohistochemistry. The present study included 49 patients (37 untreated, 12 recurrences) and the same number of age- and sex-matched healthy controls. In 24 patients ECD serum levels were determined before and 6 weeks after surgery. Mean ECD serum levels for erbB-1 and erbB-2 were 54.8+/-1.6 and 153.7+/-6.1 fmol/ml in cancer patients, and 54+/-1.5 and 147.9+/-4.5 fmol/ml in healthy controls, respectively. There was no significant difference between untreated and recurrent disease. Serum ECD follow-ups 6 weeks after surgery revealed a significant 12.3% decline of erbB-1 but no change of erbB-2 values. Immunohistochemistry showed strong staining for erbB-1 in 78% and erbB-2 in 47% of the SCCHN specimens. No correlation was detectable between receptor ECD serum levels and receptor tissue expression, tumour stage, and tumour differentiation. Hence, ECD serum levels of erbB-1 and erbB-2 are not considered to be valuable tumour markers in SCCHN.

Regulation of human head and neck squamous cell carcinoma growth in tissue culture by opioid growth factor.

Squamous cell carcinoma of the head and neck (SCCHN) is the sixth most common malignancy worldwide. Approximately half of the patients afflicted die within 5 years of diagnosis, and surviving patients may be left with severe esthetic and functional compromise. In this study, we discovered that an endogenous opioid peptide, [Met5]-enkephalin, inhibited the growth of human SCCHN in vitro; in view of this pentapeptide's action it has been termed opioid growth factor (OGF). OGF was found to be a constitutively expressed, receptor-mediated growth inhibitory agent that appears to be autocrine produced and secreted. Growth regulation was dose-related, reversible, cytostatic, and independent of serum. All 6 human SCCHN cell lines examined exhibited growth modulation by OGF. Blockade of peptide-receptor interaction by opioid antagonists (naltrexone), or addition of antibody to OGF, resulted in substantial increases in cell number compared to control levels, showing the tonic nature of OGF-zeta activity. Immunocytochemical studies detected both OGF and its related receptor, zeta, in these cells, correlating with earlier findings of peptide and receptor in specimens of SCCHN obtained at surgery. These data suggest that a native opioid peptide, OGF, interacts with a novel opioid receptor, zeta, to tonically arrest the growth of human SCCHN.