Association of Estrogen Receptor Alpha Expression With Survival in Oropharyngeal Cancer Following Chemoradiation Therapy

Exogenous Estrogen in the Development of Head and Neck Cancer

Importance

Sex differences in head and neck cancer (HNC) incidence suggest a potential contribution of sex hormones.

Objective

To assess the role of exogenous estrogen exposure in the development of HNC in female patients.

Design, Settings, and Participants

This large multicenter cohort study using clinical records from the TriNetX real-world database included 20 years of data (through May 31, 2023) from 87 health care organizations. The TriNetX database was searched for medical records for female patients with and without exogenous estrogen exposure according to their chronological age. Cohort 1 included 731 366 female patients aged 18 to 45 years old with regular oral contraceptive (OC) intake and cohort 2 included 3 886 568 patients in the same age group who did not use OC. Cohort 3 comprised 135 875 female patients at least 50 years old receiving hormone replacement therapy (HRT), whereas cohort 4 included 5 875 270 patients at least 50 years old without HRT. Propensity score matching was performed for the confounders age, alcohol dependence, and nicotine dependence. Data analyses were performed in May 2023.

Main Outcome and Measures

Diagnosis of HNC (International Statistical Classification of Diseases and Related Health Problems, Tenth Revision: C00-C14), and after propensity score matching (1:1 nearest-neighbor greedy matching), a risk analysis to investigate risk differences and risk ratios (RRs) with a 95% CI.

Results

Among the 718 101 female patients in each of cohorts 1 and 2 (mean [SD] age at diagnosis, 25.9 [6.7] years), those with OC intake had a higher risk of an HNC diagnosis (RR, 1.47; 95% CI, 1.21-1.78) than those without OC use. Among the 131 835 female patients in each of cohorts 3 and 4 (mean [SD] age, 67.9 [12.0] years), those with postmenopausal HRT intake had a lower risk of an HNC diagnosis (RR, 0.77; 95% CI, 0.64-0.92) than those without HRT use.

Conclusions and Relevance

The findings of this cohort study illustrate a positive association between OC and a negative association between HRT and the development of HNC in female patients. Given the limitations of the TriNetX database, future research should include detailed information on the intake of OC and HRT and reproductive health information (eg, age at menarche/menopause, number of pregnancies) to more accurately define the strength and direction of the possible association between exogeneous estrogen exposure and the development of HNC in female patients.

The Role of Estrogen and Estrogen Receptors in Head and Neck Tumors

Head and neck squamous cell carcinoma (HNSCC) is the most common histological form of head and neck tumors (HNTs), which originate from the epithelium of the lips and oral cavity, pharynx, larynx, salivary glands, nasal cavity, and sinuses. The main risk factors include consumption of tobacco in all forms and alcohol, as well as infections with high-risk human papillomaviruses or the Epstein-Barr virus. Regardless of the etiological agent, the risk of developing different types of HNTs is from two to more than six times higher in males than in females. The reason for such disparities probably lies in a combination of both biological and psychosocial factors. Therefore, it is hypothesized that exposure to female sex hormones, primarily estrogen, provides women with protection against the formation and metastasis of HNTs. In this review, we synthesized available knowledge on the role of estrogen and estrogen receptors (ERs) in the development and progression of HNTs, with special emphasis on membrane ERs, which are much less studied. We can summarize that in addition to epidemiologic studies unequivocally pointing to the protective effect of estrogen in women, an increased expression of both nuclear ERs, ERα, and ERβ, and membrane ERs, ERα36, GPER1, and NaV1.2, was present in different types of HNSCC, for which anti-estrogens could be used as an effective therapeutic approach.

Current and Emerging Diagnostic, Prognostic, and Predictive Biomarkers in Head and Neck Cancer

Head and neck cancers (HNC) are a biologically diverse set of cancers that are responsible for over 660,000 new diagnoses each year. Current therapies for HNC require a comprehensive, multimodal approach encompassing resection, radiation therapy, and systemic therapy. With an increased understanding of the mechanisms behind HNC, there has been growing interest in more accurate prognostic indicators of disease, effective post-treatment surveillance, and individualized treatments. This chapter will highlight the commonly used and studied biomarkers in head and neck squamous cell carcinoma.

An ESR1-Related Gene Signature Identifies Head and Neck Squamous Cell Carcinoma with Imputed Susceptibility to Endocrine Therapy

Head and neck squamous cell carcinoma (HNSCC) is associated with high morbidity and mortality. New personalized treatment strategies represent an unmet medical need to improve the overall survival and the quality of life of patients, which are often limited by the toxicity of established multimodal treatment protocols. Several studies have reported an increased expression of the estrogen receptor 1 (ESR1) in HNSCC, but its potential role in the disease outcome of these tumors remains elusive. Using an integrative analysis of multiomics and clinical data from The Cancer Genome Atlas (TCGA)-HNSC, we established a prognostic risk model based on an ESR1-related 25-gene set. The prognostic value was confirmed in an independent cohort of HNSCC and other solid tumors from TCGA. Finally, we performed in silico drug sensitivity modeling to explore potential vulnerabilities for both risk groups. This approach predicted a higher sensitivity for HNSCC, with prominent ESR1 pathway activity under treatment with specific estrogen receptor modulators. In conclusion, our data confirm the involvement of ESR1-related pathway activity in the progression of a defined subset of HNSCC, provide compelling evidence that these tumors share a specific vulnerability to endocrine therapy, and pave the way for preclinical studies and clinical trials to demonstrate the efficacy of this new therapeutic option.

Noncanonical HPV carcinogenesis drives radiosensitization of head and neck tumors

We analyzed transcriptional data from 104 HPV+ (Human papillomavirus) HNSCC (head and neck squamous cell carcinoma) tumors together with two publicly available sources to identify highly robust transcriptional programs (modules) which could be detected consistently despite heterogeneous sequencing and quantification methodologies. Among 22 modules identified, we found a single module that naturally subclassifies HPV+ HNSCC tumors based on a bimodal pattern of gene expression, clusters all atypical features of HPV+ HNSCC biology into a single subclass, and predicts patient outcome in four independent cohorts. The subclass-defining gene set was strongly correlated with Nuclear factor kappa B (NF-κB) target expression. Tumors with high expression of this NF-κB module were rarely associated with activating PIK3CA alterations or viral integration, and also expressed higher levels of HPHPV E2 and had decreased APOBEC mutagenesis. Alternatively, they harbored inactivating alterations of key regulators of NF-κB, TNF receptor associated factor 3 (TRAF3), and cylindromatosis (CYLD), as well as retinoblastoma protein (RB1). HPV+ HNSCC cells in culture with experimental depletion of TRAF3 or CYLD displayed increased expression of the subclass-defining genes, as well as robust radio-sensitization, thus recapitulating both the tumor transcriptional state and improved treatment response observed in patient data. Across all gene sets investigated, methylation to expression correlations were the strongest for the subclass-defining, NF-κB-related genes. Increased tumor-infiltrating CD4+ T cells and increased Estrogen receptors alpha (ERα) expression were identified in NF-κB active tumors. Based on the relatively high rates of cure in HPV+ HNSCC, deintensification of therapy to reduce treatment-related morbidity is being studied at many institutions. Tumor subclassification based on oncogenic subtypes may help guide the selection of therapeutic intensity or modality for patients with HPV+ HNSCC.

Tumor Cell Extrinsic Synaptogyrin 3 Expression as a Diagnostic and Prognostic Biomarker in Head and Neck Cancer

Over 70% of oropharyngeal head and neck squamous cell carcinoma (HNSC) cases in the United States are positive for human papillomavirus (HPV) yet biomarkers for stratifying oropharyngeal head and neck squamous cell carcinoma (HNSC) patient risk are limited. We used immunogenomics to identify differentially expressed genes in immune cells of HPV(+) and HPV(-) squamous carcinomas. Candidate genes were tested in clinical specimens using both quantitative RT-PCR and IHC and validated by IHC using the Carolina Head and Neck Cancer Study (CHANCE) tissue microarray of HNSC cases. We performed multiplex immunofluorescent staining to confirm expression within the immune cells of HPV(+) tumors, receiver operating characteristic (ROC) curve analyses, and assessed survival outcomes. The neuronal gene Synaptogyrin-3 (SYNGR3) is robustly expressed in immune cells of HPV(+) squamous cancers. Multiplex immunostaining and single cell RNA-seq analyses confirmed SYNGR3 expression in T cells, but also unexpectedly in B cells of HPV(+) tumors. ROC curve analyses revealed that combining SYNGR3 and p16 provides more sensitivity and specificity for HPV detection compared to p16 IHC alone. SYNGR3-high HNSC patients have significantly better prognosis with five-year OS and DSS rates of 60% and 71%, respectively. Moreover, combining p16 localization and SYNGR3 expression can further risk stratify HPV(+) patients such that high cytoplasmic, low nuclear p16 do significantly worse (Hazard Ratio, 8.6; P = 0.032) compared to patients with high cytoplasmic, high nuclear p16. SYNGR3 expression in T and B cells is associated with HPV status and enhanced survival outcomes of HNSC patients.

NF-κB over-activation portends improved outcomes in HPV-associated head and neck cancer

Evolving understanding of head and neck squamous cell carcinoma (HNSCC) is leading to more specific diagnostic disease classifications. Among HNSCC caused by the human papilloma virus (HPV), tumors harboring defects in TRAF3 or CYLD are associated with improved clinical outcomes and maintenance of episomal HPV. TRAF3 and CYLD are negative regulators of NF-κB and inactivating mutations of either leads to NF-κB overactivity. Here, we developed and validated a gene expression classifier separating HPV+ HNSCCs based on NF-κB activity. As expected, the novel classifier is strongly enriched in NF-κB targets leading us to name it the NF-κB Activity Classifier (NAC). High NF-κB activity correlated with improved survival in two independent cohorts. Using NAC, tumors with high NF-κB activity but lacking defects in TRAF3 or CYLD were identified; thus, while TRAF3 or CYLD gene defects identify the majority of tumors with NF-κB activation, unknown mechanisms leading to NF-kB activity also exist. The NAC correctly classified the functional consequences of two novel CYLD missense mutations. Using a reporter assay, we tested these CYLD mutations revealing that their activity to inhibit NF-kB was equivalent to the wild-type protein. Future applications of the NF-κB Activity Classifier may be to identify HPV+ HNSCC patients with better or worse survival with implications for treatment strategies.

Like Brothers in Arms: How Hormonal Stimuli and Changes in the Metabolism Signaling Cooperate, Leading HPV Infection to Drive the Onset of Cervical Cancer

Despite all precautionary actions and the possibility of using vaccinations to counteract infections caused by human papillomaviruses (HPVs), HPV-related cancers still account for approximately 5% of all carcinomas. Worldwide, many women are still excluded from adequate health care due to their social position and origin. Therefore, immense efforts in research and therapy are still required to counteract the challenges that this disease entails. The special thing about an HPV infection is that it is not only able to trick the immune system in a sophisticated way, but also, through genetic integration into the host genome, to use all the resources available to the host cells to complete the replication cycle of the virus without activating the alarm mechanisms of immune recognition and elimination. The mechanisms utilized by the virus are the metabolic, immune, and hormonal signaling pathways that it manipulates. Since the virus is dependent on replication enzymes of the host cells, it also intervenes in the cell cycle of the differentiating keratinocytes and shifts their terminal differentiation to the uppermost layers of the squamocolumnar transformation zone (TZ) of the cervix. The individual signaling pathways are closely related and equally important not only for the successful replication of the virus but also for the onset of cervical cancer. We will therefore analyze the effects of HPV infection on metabolic signaling, as well as changes in hormonal and immune signaling in the tumor and its microenvironment to understand how each level of signaling interacts to promote tumorigenesis of cervical cancer.

Expression of Sex Hormones in Oral Squamous Cell Carcinoma: A Systematic Review on Immunohistochemical Studies

Oral squamous cell carcinoma (OSCC) is the most widespread oral malignancy. In the western world, smoking and alcohol remain the most common risk factors, whereas smokeless tobacco and areca nut consumption are the prevalent etiological factors in South Asia. Numerous markers were studied till date to identify the disease. However, the role of sex hormones in OSCC is poorly defined. Hormonal receptors play a role in breast cancer, prostate cancer, and human papillomavirus (HPV) driven oropharyngeal cancers. It is proven that the expression of estrogen receptor-α improved the overall survival of the patient with HPV-positive oropharyngeal cancer. Thus, this review article aims to determine the expression of sex hormones by immunohistochemistry in OSCC.

This systematic review was performed with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement Criteria 2020. Relevant articles were collected from the electronic database in PubMed and Cochrane till 2021. Immunohistochemical studies on sex hormones and their role in OSCC published in English literature were included. We excluded case reports, case series, and abstract-only articles. The sample size of the selected studies varied, and these studies measured the parameters such as sex hormones and OSCC. Furthermore, all the studies used different sex hormones and their association with oral cancer through the immunohistochemical process. Thus, this review summarizes that sex hormones influence the biopathology of oral cancer and have a prognostic significance in the tumor subgroups.

Comparison of next generation sequencing, droplet digital PCR, and quantitative real-time PCR for the earlier detection and quantification of HPV in HPV-positive oropharyngeal cancer

BACKGROUND

Human papillomavirus (HPV) causes nearly 80% of oropharynx cancers diagnosed in the United States, with incidence increasing each year. Analysis of cfDNA in plasma and oral rinse has the potential to detect these cases earlier than their typical presentation, but their utility and the best method to detect HPV in plasma and oral rinse samples is unknown.

MATERIALS AND METHODS

We directly compared next generation sequencing (NGS), droplet digital PCR (ddPCR), and quantitative real-time PCR (qPCR) for their ability to detect HPV16 DNA in plasma and oral rinse from 66 patients diagnosed with HPV16-positive oropharyngeal cancer (HPV16-OPC).

RESULTS

HPV DNA detection by NGS and ddPCR in plasma samples both had good sensitivity (70%) for HPV16-OPC compared to 20.6% sensitivity by qPCR (p < 0.001). In oral rinse, NGS demonstrated a superior sensitivity of 75.0% as compared to both ddPCR (8.3%, p < 0.001) and qPCR (2.1%, p < 0.001). In a limited cohort of follow up patients, HPV levels detected in plasma by NGS but not ddPCR or qPCR reflected disease remission or progression.

CONCLUSIONS

These results suggest that NGS has the best sensitivity for detecting HPV in both plasma and oral rinse and may play a role in monitoring patients for disease recurrence. Additional studies are needed to define the specificity of NGS for similar patient cohorts.

Investigating immune and non-immune cell interactions in head and neck tumors by single-cell RNA sequencing

Head and neck squamous cell carcinoma (HNSCC) is characterized by complex relations between stromal, epithelial, and immune cells within the tumor microenvironment (TME). To enable the development of more efficacious therapies, we aim to study the heterogeneity, signatures of unique cell populations, and cell-cell interactions of non-immune and immune cell populations in 6 human papillomavirus (HPV)+ and 12 HPV- HNSCC patient tumor and matched peripheral blood specimens using single-cell RNA sequencing. Using this dataset of 134,606 cells, we show cell type-specific signatures associated with inflammation and HPV status, describe the negative prognostic value of fibroblasts with elastic differentiation specifically in the HPV+ TME, predict therapeutically targetable checkpoint receptor-ligand interactions, and show that tumor-associated macrophages are dominant contributors of PD-L1 and other immune checkpoint ligands in the TME. We present a comprehensive single-cell view of cell-intrinsic mechanisms and cell-cell communication shaping the HNSCC microenvironment.

3p Arm Loss and Survival in Head and Neck Cancer: An Analysis of TCGA Dataset

Loss of the 3p chromosome arm has previously been reported to be a biomarker of poorer outcome in both human papillomavirus (HPV)-positive and HPV-negative head and neck cancer. However, the precise operational measurement of 3p arm loss is unclear and the mutational profile associated with the event has not been thoroughly characterized. We downloaded the clinical, single nucleotide variation (SNV), copy number aberration (CNA), RNA sequencing, and reverse phase protein assay (RPPA) data from The Cancer Genome Atlas (TCGA) and The Cancer Proteome Atlas HNSCC cohorts. Survival data and hypoxia scores were downloaded from published studies. In addition, we report the inclusion of an independent Memorial Sloan Kettering cohort. We assessed the frequency of loci deletions across the 3p arm separately in HPV-positive and -negative disease. We found that deletions on chromosome 3p were almost exclusively an all or none event in the HPV-negative cohort; patients either had <1% or >97% of the arm deleted. 3p arm loss, defined as >97% deletion in HPV-positive patients and >50% in HPV-negative patients, had no impact on survival (p > 0.05). However, HPV-negative tumors with 3p arm loss presented at a higher N-category and overall stage and developed more distant metastases (p < 0.05). They were enriched for SNVs in TP53, and depleted for point mutations in CASP8, HRAS, HLA-A, HUWE1, HLA-B, and COL22A1 (false discovery rate, FDR < 0.05). 3p arm loss was associated with CNAs across the whole genome (FDR < 0.1), and pathway analysis revealed low lymphoid-non-lymphoid cell interactions and cytokine signaling (FDR < 0.1). In the tumor microenvironment, 3p arm lost tumors had low immune cell infiltration (FDR < 0.1) and elevated hypoxia (FDR < 0.1). 3p arm lost tumors had lower abundance of proteins phospho-HER3 and ANXA1, and higher abundance of miRNAs hsa-miR-548k and hsa-miR-421, which were all associated with survival. There were no molecular differences by 3p arm status in HPV-positive patients, at least at our statistical power level. 3p arm loss is largely an all or none phenomenon in HPV-negative disease and does not predict poorer survival from the time of diagnosis in TCGA cohort. However, it produces tumors with distinct molecular characteristics and may represent a clinically useful biomarker to guide treatment decisions for HPV-negative patients.

Single-cell immunoblotting resolves estrogen receptor-α isoforms in breast cancer

An array of isoforms of the nuclear estrogen receptor alpha (ER-α) protein contribute to heterogeneous response in breast cancer (BCa); yet, a single-cell analysis tool that distinguishes the full-length ER-α66 protein from the activation function-1 deficient ER-α46 isoform has not been reported. Specific detection of protein isoforms is a gap in single-cell analysis tools, as the de facto standard immunoassay requires isoform-specific antibody probes. Consequently, to scrutinize hormone response heterogeneity among BCa tumor cells, we develop a precision tool to specifically measure ER-α66, ER- α46, and eight ER-signaling proteins with single-cell resolution in the highly hetero-clonal MCF-7 BCa cell line. With a literature-validated pan-ER immunoprobe, we distinguish ER-α66 from ER-α46 in each individual cell. We identify ER-α46 in 5.5% of hormone-sensitive (MCF-7) and 4.2% of hormone-insensitive (MDA-MB-231) BCa cell lines. To examine whether the single-cell immunoblotting can capture cellular responses to hormones, we treat cells with tamoxifen and identify different sub-populations of ER-α46: (i) ER-α46 induces phospho-AKT at Ser473, (ii) S6-ribosomal protein, an upstream ER target, activates both ER-α66 and ER-α46 in MCF-7 cells, and (iii) ER-α46 partitions MDA-MB-231 subpopulations, which are responsive to tamoxifen. Unlike other single-cell immunoassays, multiplexed single-cell immunoblotting reports–in the same cell–tamoxifen effects on ER signaling proteins and on distinct isoforms of the ER-α protein.

Biologic and behavioral associations of estrogen receptor alpha positivity in head and neck squamous cell carcinoma

OBJECTIVES

Tumor HPV status is an established independent prognostic marker for oropharynx cancer (OPC). Recent studies have reported that tumor estrogen receptor alpha (ERα) positivity is also associated with prognosis independent of HPV. Little is known about the biologic and behavioral predictors of ERα positivity in head and neck squamous cell cancer (HNSCC). We therefore explored this in a multicenter prospective cohort study.

MATERIALS AND METHODS

Participants with HNSCC completed a survey and provided a blood sample. Tumor samples were tested for ERα using immunohistochemistry. ERα positivity was defined as ≥1%, standardized by the American Society of Clinical Oncology/College of American Pathologists in breast cancer. Characteristics were compared with χ² and Fisher's exact test. Odds ratios (OR) were calculated using logistic regression.

RESULTS

Of 318 patients with HNSCC, one third had ERα positive tumors (36.2%, n = 115). Odds of ERα expression were significantly increased in those with HPV-positive tumors (OR = 27.5, 95% confidence interval[CI] 12.1-62), smaller tumors (≤T2, OR = 3.6, 95% CI 1.9-7.1), male sex (OR = 2.0, 95% CI 1.1-3.6), overweight/obesity (BMI ≥ 25, OR = 1.9, 95% CI 1.1-3.3), and those married/living with a partner (OR = 1.7, 95% CI 1.0-3.0). In a multivariate model, HPV-positivity (aOR = 27.5, 95% CI 11.4-66) and small tumor size (≤T2, aOR = 2.2, 95% CI 1.0-4.8) remained independently associated with ERα status. When restricted to OPC (n = 180), tumor HPV status (aOR = 17.1, 95% CI 2.1-137) and small tumor size (≤T2, aOR = 4.0 95% CI 1.4-11.3) remained independently associated with ERα expression.

CONCLUSION

Tumor HPV status and small tumor size are independently associated with ERα expression in HNSCC.

A combination of intra-tumor genetic heterogeneity, estrogen receptor alpha and human papillomavirus status predicts outcomes in head and neck squamous cell carcinoma following chemoradiotherapy

BACKGROUND

Previous work indicates that mutant-allele tumor heterogeneity (MATH), estrogen receptor alpha (ERα) expression, and human papillomavirus (HPV) status provide prognostic utility in head and neck squamous cell carcinoma (HNSCC). We sought to assess whether the combination of these three objective biomarkers could provide better prognostication for patients who receive chemoradiotherapy (CRT).

METHODS

156 patients (75 oral cavity, 44 oropharyngeal and 37 laryngeal squamous cell carcinoma cancer patients) who received CRT as primary therapy or adjuvant to surgery were identified from The Cancer Genome Atlas (TCGA). MATH values were calculated from TCGA whole exome sequencing data, HPV status was determined by mapping RNA-seq reads, and ERα expression was determined from ESR1 mRNA expression data. Relationships among clinical characteristics were assessed by Fisher exact tests. Relationships of clinical characteristics and MATH, ERα and HPV to overall survival were evaluated with Cox proportional hazard analysis.

RESULTS

The combination of poor-prognosis values for all 3 biomarkers (high MATH, low ERα and HPV-negative status) has a predicted hazard ratio of 28.2 (95% CI: 5.4-148, p = 0.0001) versus the combination of their good-prognosis values (low MATH, high ERα and HPV-positive status). Addition of N classification to the combination of these three biomarkers added further prognostic value.

CONCLUSIONS

A combination of these three biomarkers, readily determined on pretreatment biopsy specimens, can stratify patients into prognostic groups. Their application potentially offers numerous opportunities to optimize treatment or explore de-intensification strategies in the clinical trial setting.

Single-Cell Deconvolution of Head and Neck Squamous Cell Carcinoma

Complexities in cell-type composition have rightfully led to skepticism and caution in the interpretation of bulk transcriptomic analyses. Recent studies have shown that deconvolution algorithms can be utilized to computationally estimate cell-type proportions from the gene expression data of bulk blood samples, but their performance when applied to tumor tissues, including those from head and neck, remains poorly characterized. Here, we use single-cell data (~6000 single cells) collected from 21 head and neck squamous cell carcinoma (HNSCC) samples to generate cell-type-specific gene expression signatures. We leverage bulk RNA-seq data from >500 HNSCC samples profiled by The Cancer Genome Atlas (TCGA), and using single-cell data as a reference, apply two newly developed deconvolution algorithms (CIBERSORTx and MuSiC) to the bulk transcriptome data to quantitatively estimate cell-type proportions for each tumor in TCGA. We show that these two algorithms produce similar estimates of constituent/major cell-type proportions and that a high T-cell fraction correlates with improved survival. By further characterizing T-cell subpopulations, we identify that regulatory T-cells (Tregs) were the major contributor to this improved survival. Lastly, we assessed gene expression, specifically in the Treg population, and found that TNFRSF4 (Tumor Necrosis Factor Receptor Superfamily Member 4) was differentially expressed in the core Treg subpopulation. Moreover, higher TNFRSF4 expression was associated with greater survival, suggesting that TNFRSF4 could play a key role in mechanisms underlying the contribution of Treg in HNSCC outcomes.

Identification of Prognosis-related Hub RNA Binding Proteins Function through Regulating Metabolic Processes in Tongue Cancer

RNA binding proteins (RBPs) are dysregulated and associated with the occurrence and development in various malignant tumors. However, the role of RBPs in tongue cancer are largely unclear. Here, by integrating the differential gene expression analysis and the Weighted Gene Co-expression Network Analysis (WGCNA) of TCGA-retrieved RNA-seq data, we identified a total of 171 differential co-expression RBPs. Then, in a protein-protein interaction (PPI) network containing 134 nodes (RBPs) and 315 network edges (RBP-RBP interacting networks), the top 30 hub RBPs were identified using the CytoHubba plugin of Cytoscape. Furthermore, we investigated the expression and prognostic value of these RBPs and their highly correlated networks. Among them, six RBPs (PGK1, SLC20A1, LEPR, CYP19A1, ZC3H12D, and PFKM) were shown to be the prognosis-related hub RBPs (prhRBPs). Based on these hub RBPs, we constructed a prognostic model and found that the patients in the high-risk group had dramatically poor overall survival compared to those in low-risk group. In addition, we validated the prognostic model in GSE41613, another tongue cancer patient cohort from GEO datasets. The time-dependent receiver operating characteristic (ROC) analysis of the prognostic model further confirmed the predictive capability of the risk model for tongue cancer. As suggested in functional annotation analysis, we found an intensive enrichment of these prhRBPs in metabolic pathways, including AMPK, HIF-1 signaling pathway, Glycolysis, and steroid hormone biosynthesis. Together, our study revealed the underlying role of RBP in tongue cancer biology and potentially unveiled novel targets for cancer therapy.

Estrogen receptor α as a predictive biomarker for survival in human papillomavirus-positive oropharyngeal squamous cell carcinoma

Background

Although oropharyngeal squamous cell carcinoma (OPSCC) with human papillomavirus (HPV) infection has a good prognosis, the accurate prediction of survival and risk of treatment failure is essential to design deintensification regimens. Here, we investigated estrogen receptor α (ERα) as a prognostic biomarker with therapeutic implications in OPSCC alongside factors associated with HPV infection.

Methods

We performed immunohistochemistry for ERα and p53 using formalin-fixed, paraffin-embedded tissues and assessed the HPV status using p16 immunohistochemistry and HPV DNA testing in 113 consecutive patients with OPSCC treated with surgical resection or radiotherapy/chemoradiotherapy.

Results

ERα expression and p53 alteration was observed in 35.4% and 21.2% OPSCCs; 45.6% and 1.3% p16+/HPV+ OPSCCs; and 11.5% and 76.9% p16− OPSCCs, respectively. These data suggest that OPSCC pathogenesis varies with HPV status. Furthermore, ERα expression was associated with improved overall survival (OS) in both HPV+ (p16+/HPV+ OPSCC) and p16+ (p16+ OPSCC irrespective of HPV status) models (p = 0.005 and p = 0.006, respectively) and with improved OS adjusted for stage (p = 0.037, hazard ratio: 0.109, 95% confidence interval 0.013–0.871) in the p16+ model.

Conclusions

ERα is a potential predictive biomarker for improved survival in both HPV+ and p16+ OPSCC models.

The Relationship between Estrogen-Related Signaling and Human Papillomavirus Positive Cancers

High risk-human papillomaviruses (HPVs) are known carcinogens. Numerous reports have linked the steroid hormone estrogen, and the expression of estrogen receptors (ERs), to HPV-related cancers, although the exact nature of the interactions remains to be fully elucidated. Here we will focus on estrogen signaling and describe both pro and potentially anti-cancer effects of this hormone in HPV-positive cancers. This review will summarize: (1) cell culture-related evidence, (2) animal model evidence, and (3) clinical evidence demonstrating an interaction between estrogen and HPV-positive cancers. This comprehensive review provides insights into the potential relationship between estrogen and HPV. We suggest that estrogen may provide a potential therapeutic for HPV-related cancers, however additional studies are necessary.

Estrogen Attenuates the Growth of Human Papillomavirus-Positive Epithelial Cells

Human papillomaviruses cause around 5% of all human cancers, yet there are no specific antiviral therapeutic approaches available for combatting these cancers. These cancers are currently treated with standard chemoradiation therapy (CRT). Specific antiviral reagents are desperately required, particularly for HPV+HNSCC whose incidence is increasing and for which there are no diagnostic tools available for combatting this disease. Using data from The Cancer Genome Atlas (TCGA), we and others determined that the estrogen receptor alpha (ERα) is overexpressed in HPV+HNSCC and that elevated levels are associated with an improved disease outcome. This has led to the proposal that estrogen treatment could be a novel therapeutic approach for combatting HPV+cancers. Here, we demonstrate that estrogen attenuates the growth of HPV+epithelial cells using multiple mechanisms, supporting the idea that estrogen has potential as a therapeutic agent for the treatment of HPV+HNSCC.

Human papillomaviruses (HPVs) are small, double-stranded DNA viruses that are significant risk factors in the development of cancer, and HPV accounts for approximately 5% of all worldwide cancers. Recent studies using data from The Cancer Genome Atlas (TCGA) have demonstrated that elevated levels of estrogen receptor alpha (ERα) are associated with improved survival in oropharyngeal cancers, and these elevated receptor levels were linked with human papillomavirus-positive cancers (HPV+cancers). There has been a dramatic increase in HPV-related head and neck squamous cell carcinomas (HPV+HNSCCs) over the last 2 decades, and therapeutic options for this ongoing health crisis are a priority; currently, there are no antiviral therapeutics available for combatting HPV+cancers. During our TGCA studies on head and neck cancer, we had also discovered the overexpression of ERα in HPV+cancers. Here, we demonstrate that 17β-estradiol (estrogen) attenuates the growth/cell viability of HPV+cancers in vitro, but not HPV-negative cancer cells. In addition, N/Tert-1 cells (foreskin keratinocytes immortalized with human telomerase reverse transcriptase [hTERT]) containing human papillomavirus 16 (HPV16) have elevated levels of ERα and growth sensitivity after estrogen treatment compared with parental N/Tert-1 cells. Finally, we demonstrate that there are potentially two mechanisms contributing to the attenuation of HPV+ cell growth following estrogen treatment. First, estrogen represses the viral transcriptional long control region (LCR) downregulating early gene expression, including E6/E7. Second, expression of E6 and E7 by themselves sensitizes cells to estrogen. Overall, our results support the recent proposal that estrogen could be exploited therapeutically for the treatment of HPV-positive oral cancers.

IMPORTANCE Human papillomaviruses cause around 5% of all human cancers, yet there are no specific antiviral therapeutic approaches available for combatting these cancers. These cancers are currently treated with standard chemoradiation therapy (CRT). Specific antiviral reagents are desperately required, particularly for HPV+HNSCC whose incidence is increasing and for which there are no diagnostic tools available for combatting this disease. Using data from The Cancer Genome Atlas (TCGA), we and others determined that the estrogen receptor alpha (ERα) is overexpressed in HPV+HNSCC and that elevated levels are associated with an improved disease outcome. This has led to the proposal that estrogen treatment could be a novel therapeutic approach for combatting HPV+cancers. Here, we demonstrate that estrogen attenuates the growth of HPV+epithelial cells using multiple mechanisms, supporting the idea that estrogen has potential as a therapeutic agent for the treatment of HPV+HNSCC.

Spleen tyrosine kinase expression is correlated with human papillomavirus in head and neck cancer

OBJECTIVES

Spleen tyrosine kinase (SYK) is a promoter of cell survival in a variety of cell types, including normal and cancerous epithelial cells. We hypothesized that SYK would an important therapeutic target to inhibit for the treatment of HNSCC.

MATERIALS AND METHODS

SYK protein abundance in patient tumours was evaluated. SYK protein and mRNA abundance was used to examine patient survival and human papillomavirus (HPV) status. Small-interfering RNAs and gene editing with CRISPR/Cas9 were used to evaluate SYK expression on proliferation in HNSCC cell lines. The potency of SYK inhibitor ER27319 maleate on cellular proliferation was tested using a panel of 28 HNSCC cell lines and in vivo in HNSCC patient-derived xenograft (PDX) models.

RESULTS

Moderate to high protein expression of SYK was observed in 24% of patient tumors and high SYK expression was exclusively observed in HPV-positive samples (p < 0.001). SYK inhibition with RNA interference, gene editing or a SYK inhibitor (ER27319) decreased cell proliferation and migration. Treatment of PDXs with ER27319 maleate was observed to reduce tumour burden in vivo in two of three models.

CONCLUSIONS

HPV-positive HNSCC harbours high SYK protein levels. We demonstrate that proliferation, migration and overall burden of these tumours can be reduced by genetic or pharmacologic inhibition of SYK. Taken together, these data establish SYK as a therapeutic target for HNSCC.

Elemental Zn and its Binding Protein Zinc-α2-Glycoprotein are Elevated in HPV-Positive Oropharyngeal Squamous Cell Carcinoma

Human papillomavirus (HPV)-positive head and neck squamous cell carcinoma (HNSCC) is biologically distinct from HPV-negative HNSCC. Outside of HPV-status, few tumor-intrinsic variables have been identified that correlate to improved survival. As part of exploratory analysis into the trace elemental composition of oropharyngeal squamous cell carcinoma (OPSCC), we performed elemental quanitification by X-ray fluorescence microscopy (XFM) on a small cohort (n = 32) of patients with HPV-positive and -negative OPSCC and identified in HPV-positive cases increased zinc (Zn) concentrations in tumor tissue relative to normal tissue. Subsequent immunohistochemistry of six Zn-binding proteins—zinc-α2-glycoprotein (AZGP1), Lipocalin-1, Albumin, S100A7, S100A8 and S100A9—revealed that only AZGP1 expression significantly correlated to HPV-status (p < 0.001) and was also increased in tumor relative to normal tissue from HPV-positive OPSCC tumor samples. AZGP1 protein expression in our cohort significantly correlated to a prolonged recurrence-free survival (p = 0.029), similar to HNSCC cases from the TCGA (n = 499), where highest AZGP1 mRNA levels correlated to improved overall survival (p = 0.023). By showing for the first time that HPV-positive OPSCC patients have increased intratumoral Zn levels and AZGP1 expression, we identify possible positive prognostic biomarkers in HNSCC as well as possible mechanisms of increased sensitivity to chemoradiation in HPV-positive OPSCC.

Comparison of Squamous Cell Carcinoma of the Tongue between Young and Old Patients

Background

The worldwide incidence of squamous cell carcinoma of the tongue (SCCOT) in young patients has been increasing. We investigated clinicopathologic features of this unique population and compared them with those of SCCOT in the elderly to delineate its pathogenesis.

Methods

We compared clinicopathological parameters between patients under and over 45 years old. Immunohistochemical assays of estrogen receptor, progesterone receptor, androgen receptor, p53, p16, mdm2, cyclin D1, and glutathione S-transferase P1 were also compared between them.

Results

Among 189 cases, 51 patients (27.0%) were under 45 years of age. A higher proportion of women was seen in the young group, but was not statistically significant. Smoking and drinking behaviors between age groups were similar. Histopathological and immunohistochemical analysis showed no significant difference by age and sex other than higher histologic grades observed in young patients.

Conclusions

SCCOT in young adults has similar clinicopathological features to that in the elderly, suggesting that both progress via similar pathogenetic pathways.