Prevalence of High-Risk Human Papillomavirus in Tonsil Tissue in Healthy Adults and Colocalization in Biofilm of Tonsillar Crypts.

IMPORTANCE: The pathogenesis of human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma is currently an important topic of elucidation. The presence of latent HPV infection in tonsil tissue of healthy adults may provide an explanation for a component of this process and contribute to the understanding of HPV-associated squamous cell carcinoma oncogenesis of the oropharynx. OBJECTIVE: To determine the prevalence of oropharyngeal HPV and to determine the spatial relationship between the virus and crypt biofilm in tonsil tissue. DESIGN, SETTING, AND PARTICIPANTS: A retrospective, cross-sectional study was carried out using samples obtained from tonsils that were archived at a university hospital following elective nononcologic tonsillectomy from 2012 to 2015. Samples consisted of formalin-fixed paraffin embedded samples of tumor-free tonsil tissue from 102 adults between the ages of 20 and 39 years. EXPOSURES: Human papillomavirus status was assessed by polymerase chain reaction, and high-risk subtypes 16 and 18 were assessed with quantitative polymerase chain reaction assay. Samples that demonstrated presence of HPV were then analyzed by in situ hybridization to localize the viral capsid protein. These samples were then stained with concanavalin A to establish biofilm presence and morphology. These samples were also stained with diamidino-phenylindole (DAPI) to visualize location of the virus in relation to cell nuclei. These data were then assembled for aggregate analysis to colocalize HPV in the biofilm of the tonsillar crypts. MAIN OUTCOMES AND MEASURES: Outcome measurements were determined prior to data collection and include prevalence of high-risk HPV types 16 and 18 in tonsil tissue of otherwise healthy adults, as well as demonstration with immunohistochemistry of HPV in tonsillar crypt biofilm. RESULTS: In 102 otherwise healthy adults (55 [53.9%] female; age range, 20-39 years), the overall prevalence of HPV in tonsils was 4.9% (n = 5); and high-risk type 16 or 18, 3.9% (n = 4). In this sample population, in situ hybridization colocalized HPV virus to the biofilm of the tonsillar crypts. CONCLUSIONS AND RELEVANCE: Biofilm is present in the tonsillar crypts in a considerable proportion of tonsil tissues and may be reproducibly identified. Human papillomavirus is demonstrated to colocalize to the crypt biofilm. This has important implications with respect to the determination of HPV prevalence rates in the oropharynx. It may also play a role in the pathogenesis of HPV-related oropharyngeal carcinoma.

A Novel Bromodomain Inhibitor Reverses HIV-1 Latency through Specific Binding with BRD4 to Promote Tat and P-TEFb Association.

While combinatory antiretroviral therapy (cART) can effectively reduce HIV-1 viremia, it cannot eliminate HIV-1 infection. In the presence of cART, viral reservoirs remain latent, impeding the cure of HIV-1/AIDS. Recently, latency-reversing agents (LRAs) have been developed with the intent of purging latent HIV-1, providing an intriguing strategy for the eradication of the residual viral reservoirs. Our earlier studies show that the first-generation, methyl-triazolo bromodomain, and extra-terminal domain inhibitor (BETi), JQ1, facilitates the reversal of HIV-1 latency. BETis have emerged as a new class of compounds that are promising for this HIV-1 "shock and kill" eradication approach. However, when used as a single drug, JQ1 only modestly reverses HIV-1 latency, which complicates studying the underlining mechanisms. Meanwhile, it has been widely discussed that the induction of latent proviruses is stochastic (Ho et al., 2013). Thus, new BETis are currently under active development with focus on improving potency, ease of synthesis and structural diversity. Using fluorous-tagged multicomponent reactions, we developed a novel second-generation, 3,5-dimethylisoxazole BETi based on an imidazo[1,2-a] pyrazine scaffold, UMB-32. Furthermore, we screened 37 UMB-32 derivatives and identified that one, UMB-136, reactivates HIV-1 in multiple cell models of HIV-1 latency with better efficiency than either JQ1 or UMB-32. UMB-136 enhances HIV-1 transcription and increases viral production through the release of P-TEFb. Importantly, UMB-136 enhances the latency-reversing effects of PKC agonists (prostratin, bryostatin-1) in CD8-depleted PBMCs containing latent viral reservoirs. Our results illustrate that structurally improved BETis, such as UMB-136, may be useful as promising LRAs for HIV-1 eradication.

Disease-Specific Survival with Spindle Cell Carcinoma of the Head and Neck.

OBJECTIVES: (1) Determine factors influencing survival in patients diagnosed with spindle cell carcinoma (SpCC), a rare variant of head and neck squamous cell carcinoma (SCC). (2) Compare survival of patients with SpCC to those with conventional SCC. STUDY DESIGN: Retrospective cohort study. SETTING: Surveillance, Epidemiology, and End Results 18 database (years 2004-2009). SUBJECTS AND METHODS: Among patients receiving treatment for a single primary in the oral cavity, oropharynx, hypopharynx, or larynx, 118 subjects with SpCC and 18,298 subjects with SCC were identified with complete data for the variables of age, sex, grade, tumor size, stage group, and TNM stage. Disease-specific survival curves were compared. Univariate and multivariate analyses were used to examine the effects of each factor on survival over all sites and within each of 3 sites. RESULTS: Univariate analysis of the combination of the 3 anatomic subsites showed survival with SpCC was worse than with conventional SCC (P < .001). Three-year disease-specific survival with SpCC was 49.5%, and 5-year disease-specific survival was 40.2%. Compared with conventional SCC, survival was worse for SpCC of the oral cavity (P < .001) and oropharynx (P < .001) but no different for the larynx and hypopharynx site (P = .15). Multivariate analysis identified age (P = .02), tumor size (P = .006), and M stage (P < .001) as the only variables significantly affecting survival with SpCC. All variables significantly affected survival with conventional SCC. CONCLUSIONS: Spindle cell carcinoma carries a worse prognosis than SCC. Larger tumor size, older age, and metastatic disease portend worse survival with SpCC of the head and neck.

The effect of antibiotics on the microbiome in acute exacerbations of chronic rhinosinusitis.

BACKGROUND: Current treatment of acute exacerbations of chronic rhinosinusitis (CRS) is driven by identification of predominant bacteria using culture-based methods and determination of antibiotic sensitivities. The objective of this study was to evaluate the response of the sinonasal microbiome to antibiotic therapy in the setting of an acute exacerbation of CRS. METHODS: Aspirate and swab samples for culture and DNA analysis were collected bilaterally from 8 CRS patients presenting with acute exacerbations. Patients were started on a 2-week course of a culture-directed antibiotic after sensitivities were determined. Repeat samples were taken immediately on the completion of treatment. DNA was extracted from each sample, amplified using bacterial 16S primers and sequenced. Bacterial abundance was determined by quantitative polymerase chain reaction (qPCR). Diversity metrics of the microbiota between pretreatment and posttreatment samples were calculated. RESULTS: There was significantly more bacterial DNA present in the pretreatment group than in the posttreatment group. An increase in α-diversity was found in the posttreatment group relative to the pretreatment group (p < 0.05 in each comparison) with swab sampling, but not by aspirate sampling. The predominant organism identified by 16S sequencing correlated with the culture-identified bacteria genus in each patient. CONCLUSION: Significant differences exist in the diversity of bacteria populations during acute exacerbations of CRS and after antimicrobial treatment. After therapy, the increase in diversity is accompanied by a decrease in the total of abundance of the bacterial population.

Human papillomavirus-active head and neck cancer and ethnic health disparities.

OBJECTIVES/HYPOTHESIS: Mortality for black males with head and neck squamous cell carcinoma (HNSCC) is twice that of white males or females. Human papillomavirus (HPV)-active HNSCC, defined by the concurrent presence of high-risk type HPV DNA and host cell p16(INK4a) expression, is associated with decreased mortality. We hypothesized that prevalence of this HPV-active disease class would be lower in black HNSCC patients compared to white patients. STUDY DESIGN: Multi-institutional retrospective cohort analysis. METHODS: Real-time polymerase chain reaction was used to evaluate for high-risk HPV DNA presence. Immunohistochemistry for p16(INK4a) protein was used as a surrogate marker for HPV oncoprotein activity. Patients were classified as HPV-negative (HPV DNA-negative, p16(INK4a) low), HPV-inactive (HPV DNA-positive, p16(INK4a) low), and HPV-active (HPV DNA-positive, p16(INK4a) high). Overall survival and recurrence rates were compared by Fisher exact test and Kaplan-Meier analysis. RESULTS: There were 140 patients with HNSCC who met inclusion criteria. Self-reported ethnicity was white (115), black (25), and other (0). Amplifiable DNA was recovered from 102/140 patients. The presence of HPV DNA and the level of p16(INK4a) expression were determined, and the results were used to classify these patients as HPV-negative (44), HPV-inactive (33), and HPV-active (25). Patients with HPV-active HNSCC had improved overall 5-year survival (59.7%) compared to HPV-negative and HPV-inactive patients (16.9%) (P = .003). Black patients were less likely to have HPV-active disease (0%) compared to white patients (21%) (P = .017). CONCLUSIONS: The favorable HPV-active disease class is less common in black than in white patients with HNSCC, which appears to partially explain observed ethnic health disparities.

Use of a microscope stage-mounted Nickel-63 microirradiator for real-time observation of the DNA double-strand break response.

Eukaryotic cells begin to assemble discrete, nucleoplasmic repair foci within seconds after the onset of exposure to ionizing radiation. Real-time imaging of this assembly has the potential to further our understanding of the effects of medical and environmental radiation exposure. Here, we describe a microirradiation system for targeted delivery of ionizing radiation to individual cells without the need for specialized facilities. The system consists of a 25-micron diameter electroplated Nickel-63 electrode, enveloped in a glass capillary and mounted in a micromanipulator. Because of the low energy of the beta radiation and the minute total amount of isotope present on the tip, the device can be safely handled with minimum precautions. We demonstrate the use of this system for tracking assembly of individual repair foci in real time in live U2OS human osteosarcoma cells. Results indicate that there is a subset of foci that appear and disappear rapidly, before a plateau level is reached approximately 30 min post-exposure. This subset of foci would not have been evident without real-time observation. The development of a microirradiation system that is compatible with a standard biomedical laboratory expands the potential for real-time investigation of the biological effects of ionizing radiation.

Multi-spectral imaging analysis of HSPB1 expression in head and neck squamous cell carcinoma.

The objective of this study was to obtain more accurate quantitation of HSPB1 expression in HNSCC using a novel quantitative protein expression analysis system based on multispectral imaging. The study was a retrospective laboratory study of HNSCC patients treated at tertiary care academic medical center. Archival tissue samples from forty seven patients with HNSCC were subjected to immunohistochemistry using primary antibody to HSPB1. Seven of the patients had early stage cancers (TNM stage I/II) and forty patients had advanced stage cancers (TNM stage III/IV). HSPB1 expression was increased in advanced stage versus early stage cancers. Further investigation of HSPB1 as a potential biomarker for HNSCC is warranted.

Significance of HSPB1 expression in head and neck squamous cell carcinoma: a meta-analysis of published literatures.

OBJECTIVE: HSPB1 functions to prevent stress-induced cellular damage and has is elevated in multiple cancer types. The significance of HSPB1 in HNSCC remains controversial. We sought to perform a meta-analysis of HSPB1 expression to clarify previous findings. STUDY DESIGN: Meta-analysis of all published studies of HSPB1 in HNSCC patients using IHC techniques. METHODS: A literature review was performed on PubMed and Google Scholar search engines using terms HSP27, HSPB1, Heat Shock Proteins, Cancer, Head and Neck Squamous Cell Carcinoma. Additional studies were added by review of manuscript bibliographies. Means and standard deviations for continuous data were obtained for overall HSPB1 expression (in cancer, normal and dysplasia), nodal status and TNM stage. Chi-square and Cochran's Q test were used to test statistical significance. RESULTS: There were 77 studies identified in the context of HSPB1 and cancer in general. Of these, 7 studies (total patients n=347) met inclusion criteria and reported findings in HNSCC using IHC scoring techniques. For the mean difference in HSPB1 expression; cancer vs. normal, cancer vs. dysplasia, and dysplasia vs. normal all showed significance (p<0.0001) however the difference was not homogeneous across studies for cancer vs. dysplasia and normal. The difference was homogeneous for dysplasia vs. normal. There was no significant difference for HSPB1 expression by nodal status or stage. CONCLUSION: HSPB1 is elevated in HNSCC and may be a useful biomarker for this disease.

Characterization of Molecular Markers Indicative of Cervical Cancer Progression.

Cervical cancer originates with human papillomavirus (HPV) infection and progresses via histologically-defined premalignant stages. Here we compare normal cervical epithelium and patient-matched high grade squamous intraepithelial lesions (HSIL) with cervical carcinoma tissue from the same patient population (n=10 per group). Specimens were analyzed by combined laser capture microdissection and 2D-DIGE. Significant expression changes were seen with 53 spots resulting in identification of 23 unique proteins at the molecular level. These include eight that uniquely distinguish normal epithelium and HSIL and four that uniquely distinguish HSIL and carcinoma. In addition, one protein, cornulin, distinguishes all three states. Other identified proteins included differentiation markers, oncogene DJ-1, serpins, stress and interferon-responsive proteins, detoxifying enzymes, and serum transporters. A literature review, performed for all identified proteins, allowed most changes to be assigned to one of three causes: direct or indirect HPV oncoprotein interactions, growth selection during latency, or interactions in the lesion microenvironment. Selected findings were confirmed by immunohistochemistry using either frozen sections from the same cohort or formalin fixed paraffin embedded samples from a tissue microarray. Novel markers described here have potential applications for increasing the predictive value of current screening methods.

2D-DIGE proteomic characterization of head and neck squamous cell carcinoma.

OBJECTIVE: Identify proteins that are differentially expressed between head and neck squamous cell cancer (HNSCC) and patient-matched normal adjacent tissue, and validate findings in a separate patient cohort. STUDY DESIGN: Cross-sectional study of surgical specimens. SETTING: Tertiary care academic medical center. SUBJECTS AND METHODS: Laser capture microdissection and two-dimensional difference gel electrophoresis were used previously to establish proteomic profiles for tumor and normal adjacent tissue from 14 patients. Here, significance analysis of microarray was used to rank candidate biomarkers. Spots meeting statistical and biological criteria of significance were analyzed by liquid chromatography and tandem mass spectrometry to obtain protein identifications. The expression pattern of the highest-ranked candidate biomarker (cornulin) was validated in a larger, independent patient cohort (n = 68) by immunohistochemical staining of a tissue microarray. RESULTS: Of 732 spots, 117 (15.9%) met criteria for significance. Identities were obtained for 39 spots, representing 17 different proteins. Four proteins were novel in the context of HNSCC: glutathione synthetase, which was upregulated; and cornulin (squamous epithelial heat shock protein 53), guanylate binding protein 6, and heat shock 70 kDa protein 5 (glucose-regulated protein, 78 kDa), which were downregulated. Cornulin functions in the stress response in normal squamous epithelium, and reduced expression has been proposed as a marker of susceptibility to laryngopharyngeal reflux and other stressors. Loss of cornulin expression was confirmed in an independent HNSCC patient cohort (P < 0.001). CONCLUSIONS: Downregulation of cornulin is a prominent feature of the molecular signature of HNSCC identified by comparative proteomics. Cornulin may represent a link between HNSCC and other pathologies arising in stratified squamous epithelium.

Defining molecular phenotypes of human papillomavirus-associated oropharyngeal squamous cell carcinoma: validation of three-class hypothesis.

OBJECTIVE: The purpose of this study was to determine if oropharyngeal squamous cell carcinoma (OSCC) classified into three groups based on human papillomavirus (HPV) 16 DNA presence and p16 expression display different protein expression patterns. STUDY DESIGN: Cross-sectional study. SETTING: A laboratory-based study of patients with OSCC treated at a tertiary care academic medical center. SUBJECTS AND METHODS: Paraffin-embedded OSCC specimens from 77 patients classified into the three-class model (HPV negative, HPV inactive [HPV16+/p16-], and HPV active [HPV16+/p16+]) were queried for the expression of 14 tumor progression proteins using AQUA (HistoRx, New Haven CT). Protein expression between groups was assessed by analysis of variance. Global expression patterns were determined by unsupervised hierarchical clustering. RESULTS: There were significant differences in expression of beta-catenin (P = 0.009), epidermal growth factor receptor (P = 0.009), and vascular endothelial growth factor (P = 0.028) between groups. HPV-active tumors had overexpression of beta-catenin. Hierarchical clustering showed HPV-negative and HPV-inactive tumors displayed association patterns distinct from HPV-active tumors. CONCLUSIONS: Tumors classified by HPV DNA presence and p16 expression have different molecular phenotypes. This is the first demonstration of overexpression of beta-catenin (also found in HPV-caused cervical cancer) in HPV-active OSCC. HPV-active OSCC may share a similar ontogeny to HPV-caused cervical cancer.

Large-scale analysis of protein expression changes in human keratinocytes immortalized by human papilloma virus type 16 E6 and E7 oncogenes.

BACKGROUND: Infection with high-risk type human papilloma viruses (HPVs) is associated with cervical carcinomas and with a subset of head and neck squamous cell carcinomas. Viral E6 and E7 oncogenes cooperate to achieve cell immortalization by a mechanism that is not yet fully understood. Here, human keratinocytes were immortalized by long-term expression of HPV type 16 E6 or E7 oncoproteins, or both. Proteomic profiling was used to compare expression levels for 741 discrete protein features. RESULTS: Six replicate measurements were performed for each group using two-dimensional difference gel electrophoresis (2D-DIGE). The median within-group coefficient of variation was 19-21%. Significance of between-group differences was tested based on Significance Analysis of Microarray and fold change. Expression of 170 (23%) of the protein features changed significantly in immortalized cells compared to primary keratinocytes. Most of these changes were qualitatively similar in cells immortalized by E6, E7, or E6/7 expression, indicating convergence on a common phenotype, but fifteen proteins (~2%) were outliers in this regulatory pattern. Ten demonstrated opposite regulation in E6- and E7-expressing cells, including the cell cycle regulator p16INK4a; the carbohydrate binding protein Galectin-7; two differentially migrating forms of the intermediate filament protein Cytokeratin-7; HSPA1A (Hsp70-1); and five unidentified proteins. Five others had a pattern of expression that suggested cooperativity between the co-expressed oncoproteins. Two of these were identified as forms of the small heat shock protein HSPB1 (Hsp27). CONCLUSION: This large-scale analysis provides a framework for understanding the cooperation between E6 and E7 oncoproteins in HPV-driven carcinogenesis.

Use of combination proteomic analysis to demonstrate molecular similarity of head and neck squamous cell carcinoma arising from different subsites.

OBJECTIVE: To evaluate head and neck squamous cell carcinomas (HNSCCs) for differences in protein expression between oral cavity, oropharynx, larynx, and hypopharynx subsites. DESIGN: Retrospective proteomic analysis using tissue microarray (TMA) and 2-dimensional difference gel electrophoresis (2D-DIGE). For the TMA, automated quantitative protein expression analysis was used to interrogate levels of 4 cell-cycle regulatory proteins chosen for their known roles in cancer (cyclin D1, p53, Rb, and p14). For the 2D-DIGE, lesional and normal adjacent tissues were enriched by laser capture microdissection. Total protein was extracted, analyzed by 2D-DIGE with saturation dye labeling, and evaluated for relative abundance levels of individual protein spots. SETTING: Two tertiary-care academic medical centers. PATIENTS: Seventy-one patients with HNSCC for TMA, and 14 patients with HNSCC with frozen tumor and normal tissue for 2D-DIGE. RESULTS: The automated quantitative analysis of protein expression analysis revealed no difference between subsite for cyclin D1, p53, Rb, or p14 expression. The 2D-DIGE study was based on 28 gels (14 cancer gels and 14 adjacent normal gels), and 732 spots were identified as matching across more than 90% of gels. Significance was evaluated based on false discovery rate (FDR) estimated from permuted data sets. There were no significant differences in protein expression between subsites (FDR greater than or equal to 30% in all instances). CONCLUSIONS: Observed differences in outcomes between HNSCCs from different subsites may not reflect differences in tumor biologic characteristics between subsites. Rather, it is possible that observed clinical heterogeneity among HNSCCs may be based on other factors, such as viral vs chemical carcinogenesis.