Theresa Guo

Human Papillomavirus-Related Carcinomas of the Sinonasal Tract

High-risk human papillomavirus (HPV) is an established cause of head and neck carcinomas arising in the oropharynx. The presence of HPV has also been reported in some carcinomas arising in the sinonasal tract, but little is known about their overall incidence or their clinicopathologic profile. The surgical pathology archives of The Johns Hopkins Hospital were searched for all carcinomas arising in the sinonasal tract from 1995 to 2011, and tissue microarrays were constructed. p16 immunohistochemical analysis and DNA in situ hybridization for high-risk types of HPV were performed. Demographic and clinical outcome data were extracted from patient medical records. Of 161 sinonasal carcinomas, 34 (21%) were positive for high-risk HPV DNA, including type 16 (82%), type 31/33 (12%), and type 18 (6%). HPV-positive carcinomas consisted of 28 squamous cell carcinomas and variants (15 nonkeratinizing or partially keratinizing, 4 papillary, 5 adenosquamous, 4 basaloid), 1 small cell carcinoma, 1 sinonasal undifferentiated carcinoma, and 4 carcinomas that were difficult to classify but exhibited adenoid cystic carcinoma-like features. Immunohistochemistry for p16 was positive in 59/161 (37%) cases, and p16 expression strongly correlated with the presence of HPV DNA: 33 of 34 (97%) HPV-positive tumors exhibited high p16 expression, whereas only 26 of 127 (20%) HPV-negative tumors were p16 positive (P<0.0001). The HPV-related carcinomas occurred in 19 men and 15 women ranging in age from 33 to 87 years (mean, 54 y). A trend toward improved survival was observed in the HPV-positive group (hazard ratio=0.58, 95% confidence interval [0.26, 1.28]). The presence of high-risk HPV in 21% of sinonasal carcinomas confirms HPV as an important oncologic agent of carcinomas arising in the sinonasal tract. Although nonkeratinizing squamous cell carcinoma is the most common histologic type, there is a wide morphologic spectrum of HPV-related disease that includes a variant that resembles adenoid cystic carcinoma. The distinctiveness of these HPV-related carcinomas of the sinonasal tract with respect to risk factors, clinical behavior, and response to therapy remains to be clarified.

Detection of somatic mutations and HPV in the saliva and plasma of patients with head and neck squamous cell carcinomas

Tumor DNA in saliva and plasma can provide a noninvasive biomarker for head and neck squamous cell carcinoma. A cancer test that’s worth a spit Head and neck squamous cell carcinoma is one of the most common cancers worldwide, and its incidence is increasing. This is a difficult-to-treat cancer for which few targeted agents are available, and there are no biomarkers for monitoring therapeutic progress. Wang et al. discovered that tumor DNA can be detected and analyzed in the blood of most patients with head and neck cancers, as well as in the saliva of those with cancers of the oral cavity. Moreover, they found preliminary evidence suggesting that tumor DNA may be detectable in saliva before clinical evidence of tumor recurrence, which may be useful for patient monitoring if this result is confirmed in larger studies. To explore the potential of tumor-specific DNA as a biomarker for head and neck squamous cell carcinomas (HNSCC), we queried DNA from saliva or plasma of 93 HNSCC patients. We searched for somatic mutations or human papillomavirus genes, collectively referred to as tumor DNA. When both plasma and saliva were tested, tumor DNA was detected in 96% of 47 patients. The fractions of patients with detectable tumor DNA in early- and late-stage disease were 100% (n = 10) and 95% (n = 37), respectively. When segregated by site, tumor DNA was detected in 100% (n = 15), 91% (n = 22), 100% (n = 7), and 100% (n = 3) of patients with tumors of the oral cavity, oropharynx, larynx, and hypopharynx, respectively. In saliva, tumor DNA was found in 100% of patients with oral cavity cancers and in 47 to 70% of patients with cancers of the other sites. In plasma, tumor DNA was found in 80% of patients with oral cavity cancers, and in 86 to 100% of patients with cancers of the other sites. Thus, saliva is preferentially enriched for tumor DNA from the oral cavity, whereas plasma is preferentially enriched for tumor DNA from the other sites. Tumor DNA in saliva was found postsurgically in three patients before clinical diagnosis of recurrence, but in none of the five patients without recurrence. Tumor DNA in the saliva and plasma appears to be a potentially valuable biomarker for detection of HNSCC.

A polymorphism in IRF4 affects human pigmentation through a tyrosinase-dependent MITF/TFAP2A pathway.

Sequence polymorphisms linked to human diseases and phenotypes in genome-wide association studies often affect noncoding regions. A SNP within an intron of the gene encoding Interferon Regulatory Factor 4 (IRF4), a transcription factor with no known role in melanocyte biology, is strongly associated with sensitivity of skin to sun exposure, freckles, blue eyes, and brown hair color. Here, we demonstrate that this SNP lies within an enhancer of IRF4 transcription in melanocytes. The allele associated with this pigmentation phenotype impairs binding of the TFAP2A transcription factor that, together with the melanocyte master regulator MITF, regulates activity of the enhancer. Assays in zebrafish and mice reveal that IRF4 cooperates with MITF to activate expression of Tyrosinase (TYR), an essential enzyme in melanin synthesis. Our findings provide a clear example of a noncoding polymorphism that affects a phenotype by modulating a developmental gene regulatory network.

Surgical salvage improves overall survival for patients with HPV‐positive and HPV‐negative recurrent locoregional and distant metastatic oropharyngeal cancer

Human papillomavirus (HPV) tumor status and surgical salvage are associated with improved prognosis for patients with recurrent oropharyngeal squamous cell carcinoma (OPSCC). Current data regarding types of surgery and the impact of surgery for patients with distant metastatic disease are limited.

Antagonistic cross-regulation between Sox9 and Sox10 controls an anti-tumorigenic program in melanoma.

Melanoma is the most fatal skin cancer, but the etiology of this devastating disease is still poorly understood. Recently, the transcription factor Sox10 has been shown to promote both melanoma initiation and progression. Reducing SOX10 expression levels in human melanoma cells and in a genetic melanoma mouse model, efficiently abolishes tumorigenesis by inducing cell cycle exit and apoptosis. Here, we show that this anti-tumorigenic effect functionally involves SOX9, a factor related to SOX10 and upregulated in melanoma cells upon loss of SOX10. Unlike SOX10, SOX9 is not required for normal melanocyte stem cell function, the formation of hyperplastic lesions, and melanoma initiation. To the contrary, SOX9 overexpression results in cell cycle arrest, apoptosis, and a gene expression profile shared by melanoma cells with reduced SOX10 expression. Moreover, SOX9 binds to the SOX10 promoter and induces downregulation of SOX10 expression, revealing a feedback loop reinforcing the SOX10 low/SOX9 high ant,m/ii-tumorigenic program. Finally, SOX9 is required in vitro and in vivo for the anti-tumorigenic effect achieved by reducing SOX10 expression. Thus, SOX10 and SOX9 are functionally antagonistic regulators of melanoma development.

The potential impact of prophylactic human papillomavirus vaccination on oropharyngeal cancer

The incidence of oropharyngeal cancer (OPC) is significantly increasing in the United States. Given that these epidemiologic trends are driven by human papillomavirus (HPV), the potential impact of prophylactic HPV vaccines on the prevention of OPC is of interest. The primary evidence supporting the approval of current prophylactic HPV vaccines is from large phase 3 clinical trials focused on the prevention of genital disease (cervical and anal cancer, as well as genital warts). These trials reported vaccine efficacy rates of 89% to 98% for the prevention of both premalignant lesions and persistent genital infections. However, these trials were designed before the etiologic relationship between HPV and OPC was established. There are differences in the epidemiology of oral and genital HPV infection, such as differences in age and sex distributions, which suggest that the vaccine efficacy observed in genital cancers may not be directly translatable to the cancers of the oropharynx. Evaluation of vaccine efficacy is challenging in the oropharynx because no premalignant lesion analogous to cervical intraepithelial neoplasia in cervical cancer has yet been identified. To truly investigate the efficacy of these vaccines in the oropharynx, additional clinical trials with feasible endpoints are needed. Cancer 2016;122:2313–2323.

Outlier analysis defines zinc finger gene family DNA methylation in tumors and saliva of head and neck cancer patients

Head and Neck Squamous Cell Carcinoma (HNSCC) is the fifth most common cancer, annually affecting over half a million people worldwide. Presently, there are no accepted biomarkers for clinical detection and surveillance of HNSCC. In this work, a comprehensive genome-wide analysis of epigenetic alterations in primary HNSCC tumors was employed in conjunction with cancer-specific outlier statistics to define novel biomarker genes which are differentially methylated in HNSCC. The 37 identified biomarker candidates were top-scoring outlier genes with prominent differential methylation in tumors, but with no signal in normal tissues. These putative candidates were validated in independent HNSCC cohorts from our institution and TCGA (The Cancer Genome Atlas). Using the top candidates, ZNF14, ZNF160, and ZNF420, an assay was developed for detection of HNSCC cancer in primary tissue and saliva samples with 100% specificity when compared to normal control samples. Given the high detection specificity, the analysis of ZNF DNA methylation in combination with other DNA methylation biomarkers may be useful in the clinical setting for HNSCC detection and surveillance, particularly in high-risk patients. Several additional candidates identified through this work can be further investigated toward future development of a multi-gene panel of biomarkers for the surveillance and detection of HNSCC.

Disease-free survival after salvage therapy for recurrent oropharyngeal squamous cell carcinoma

Factors associated with disease‐free survival (DFS) after salvage therapy for recurrent oropharyngeal squamous cell carcinoma (SCC) in the context of human papillomavirus (HPV) are poorly understood.

Characterization of functionally active gene fusions in human papillomavirus related oropharyngeal squamous cell carcinoma.

The Cancer Genome Atlas (TCGA) sequencing analysis of head and neck squamous cell carcinoma (HNSCC) recently reported on gene fusions, however, few human papillomavirus (HPV) positive samples were included, and the functional relevance of identified fusions was not explored. We therefore performed an independent analysis of gene fusions in HPV‐positive oropharyngeal SCC (OPSCC). RNA sequencing was performed on 47 HPV‐positive OPSCC primary tumors and 25 normal mucosal samples from cancer unaffected controls on an Illumina TruSeq platform. MapSplice2 was used for alignment and identification of fusion candidates. Putative fusions with less than five spanning reads, detected in normal tissues, or that mapped to the same gene were filtered out. Selected fusions were validated by RT‐PCR and Sanger sequencing. Within 47 HPV‐positive OPSCC tumors, 282 gene fusions were identified. Most fusions (85.1%) occurred in a single tumor, and the remaining fusions recurred in 2–16 tumors. Gene fusions were associated with significant up regulation of 16 genes (including EGFR and ERBB4) and down regulation of four genes (PTPRT, ZNF750, DLG2, SLCO5A1). Expression of these genes followed similar patterns of up regulation and down regulation in tumors without these fusions compared to normal tissue. Five of six gene fusions selected for validation were confirmed through RT‐PCR and sequencing. This integrative analysis provides a method of prioritizing functionally relevant gene fusions that may be expanded to other tumor types. These results demonstrate that gene fusions may be one mechanism by which functionally relevant genes are altered in HPV‐positive OPSCC.

Molecular Biology and Immunology of Head and Neck Cancer

In recent years, our knowledge and understanding of head and neck squamous cell carcinoma (HNSCC) has expanded dramatically. New high-throughput sequencing technologies have accelerated these discoveries since the first reports of whole-exome sequencing of HNSCC tumors in 2011. In addition, the discovery of human papillomavirus in relationship with oropharyngeal squamous cell carcinoma has shifted our molecular understanding of the disease. New investigation into the role of immune evasion in HNSCC has also led to potential novel therapies based on immune-specific systemic therapies.