Human Papillomavirus Drives Tumor Development Throughout the Head and Neck: Improved Prognosis Is Associated With an Immune Response Largely Restricted to the Oropharynx

Molecular patterns and mechanisms of tumorigenesis in HPV-associated and HPV-independent sinonasal squamous cell carcinoma

Mechanisms of tumorigenesis in sinonasal squamous cell carcinoma (SNSCC) remain poorly described due to its rare nature. A subset of SNSCC are associated with the human papillomavirus (HPV); however, it is unknown whether HPV is a driver of HPV-associated SNSCC tumorigenesis or merely a neutral bystander. We hypothesized that performing the first large high-throughput sequencing study of SNSCC would reveal molecular mechanisms of tumorigenesis driving HPV-associated and HPV-independent SNSCC and identify targetable pathways. High-throughput sequencing was performed on 64 patients with HPV-associated and HPV-independent sinonasal carcinomas. Mutation annotation, viral integration, copy number, and pathway-based analyses were performed. Analysis of HPV-associated SNSCC revealed similar mutational patterns observed in HPV-associated cervical and head and neck squamous cell carcinoma, including lack of TP53 mutations and the presence of known hotspot mutations in PI3K and FGFR3. Further similarities included enrichment of APOBEC mutational signature, viral integration at known hotspot locations, and frequent mutations in epigenetic regulators. HPV-associated SNSCC-specific recurrent mutations were also identified including KMT2C , UBXN11 , AP3S1 , MT-ND4 , and MT-ND5 . Mutations in KMT2D and FGFR3 were associated with decreased overall survival. We developed the first known HPV-associated SNSCC cell line and combinatorial small molecule inhibition of YAP/TAZ and PI3K pathways synergistically inhibited tumor cell clonogenicity. In conclusion, HPV-associated SNSCC and HPV-independent SNSCC are driven by molecularly distinct mechanisms of tumorigenesis. Combinatorial blockade of YAP/TAZ and vertical inhibition of the PI3K pathway may be useful in targeting HPV-associated SNSCC whereas targeting MYC and horizontal inhibition of RAS/PI3K pathways for HPV-independent SNSCC.

One Sentence Summary

This study solidifies HPV as a driver of HPV-associated SNSCC tumorigenesis, identifies molecular mechanisms distinguishing HPV-associated and HPV-independent SNSCC, and elucidates YAP/TAZ and PI3K blockade as key targets for HPV-associated SNSCC.

Oral and periodontal manifestation related during human papilloma virus infections: Update on early prognostic factors

Human Papilloma Virus (HPV) is considered one of the most common sexually transmitted infections and has been shown to play an important role in the pathogenesis of squamous cell carcinomas (SCC) of the cervix and head and neck. Manifestations of HPV infections can be manifold, ranging from asymptomatic infections to benign or potentially malignant lesions to intraepithelial neoplasms and invasive carcinomas. The heterogeneity of clinical manifestations from HPV infection depends on the interactions between the viral agent and the host, a direct consequence of the ability on the part of HPV is to remain silent and to evade and convey the action of the host immune system. The oral mucosa represents one of the tissues for which HPV has a distinct tropism and is frequently affected by infection. While much information is available on the role that HPV infection plays in the development of SCC in the oral cavity, there is less information on asymptomatic infections and benign HPV-induced oral lesions. Therefore, the purpose of this review is to analyze, in light of current knowledge, the early clinical and bio-humoral prognostic features related to the risk of HPV malignant transformation, focusing on subclinical conditions, benign lesions, and the correlation between oral infection and infection in other districts. The data show that the main risk associated with HPV infection is related to malignant transformation of lesions. Although HPV-driven OPSCC is associated with a better prognosis than non-HPV-driven OPSCC, primary prevention and early detection of the infection and affected genotype are essential to reduce the risk of malignant neoplastic complications and improve the prognosis.

Metabolic pathway-based subtypes associate glycan biosynthesis and treatment response in head and neck cancer

Head and Neck Squamous Cell Carcinoma (HNSCC) is a heterogeneous malignancy that remains a significant challenge in clinical management due to frequent treatment failures and pronounced therapy resistance. While metabolic dysregulation appears to be a critical factor in this scenario, comprehensive analyses of the metabolic HNSCC landscape and its impact on clinical outcomes are lacking. This study utilized transcriptomic data from four independent clinical cohorts to investigate metabolic heterogeneity in HNSCC and define metabolic pathway-based subtypes (MPS). In HPV-negative HNSCCs, MPS1 and MPS2 were identified, while MPS3 was enriched in HPV-positive cases. MPS classification was associated with clinical outcome post adjuvant radio(chemo)therapy, with MPS1 consistently exhibiting the highest risk of therapeutic failure. MPS1 was uniquely characterized by upregulation of glycan (particularly chondroitin/dermatan sulfate) metabolism genes. Immunohistochemistry and pilot mass spectrometry imaging analyses confirmed this at metabolite level. The histological context and single-cell RNA sequencing data identified the malignant cells as key contributors. Globally, MPS1 was distinguished by a unique transcriptomic landscape associated with increased disease aggressiveness, featuring motifs related to epithelial-mesenchymal transition, immune signaling, cancer stemness, tumor microenvironment assembly, and oncogenic signaling. This translated into a distinct histological appearance marked by extensive extracellular matrix remodeling, abundant spindle-shaped cancer-associated fibroblasts, and intimately intertwined populations of malignant and stromal cells. Proof-of-concept data from orthotopic xenotransplants replicated the MPS phenotypes on the histological and transcriptome levels. In summary, this study introduces a metabolic pathway-based classification of HNSCC, pinpointing glycan metabolism-enriched MPS1 as the most challenging subgroup that necessitates alternative therapeutic strategies.

Risk factors for immune-related adverse effects during CPI therapy in patients with head and neck malignancies - a single center study

Introduction

Checkpoint inhibitors, such as PD1 inhibitors, represent an important pillar in the therapy of advanced malignancies of the head and neck region. The most relevant complications are immune-related adverse effects (irAEs), which represent an immense burden for patients. Currently, no sufficient stratification measures are available to identify patients at increased risk of irAEs. The aim of this retrospective study was to examine whether demographic, histopathological, clinical, or laboratory values at the start of CPI therapy represent a risk factor for the later occurrence of autoimmune complications.

Material and methods

Data from 35 patients between 2018 and 2021 who received therapy with nivolumab or pembrolizumab for head and neck malignancy were analyzed and assessed for any associations with the subsequent occurrence of irAEs.

Results

IrAE developed in 37% of patients, with pneumonitis being the most common form (14%). Pneumonitis was found in patients with an average significantly lower T-stage of primary tumors. An increase in basophilic leukocytes was found in patients with dermatitis later in the course. When thyroiditis developed later, the patients had a higher CPS score and lower monocyte levels.

Discussion

Even though individual laboratory values at the beginning of therapy might show a statistical association with the later occurrence of irAEs, neither demographic, histopathological, nor laboratory chemistry values seem to be able to generate a sound and reliable risk profile for this type of complication. Therefore, patients need to be educated and sensitized to irAEs, and regular screening for irAEs should be carried out.

DNA-methylome-derived epigenetic fingerprint as an immunophenotype indicator of durable clinical immunotherapeutic benefits in head and neck squamous cell carcinoma

BACKGROUND

Cancer immunotherapy provides durable response and improves survival in a subset of head and neck squamous cell carcinoma (HNSC) patients, which may due to discriminative tumor microenvironment (TME). Epigenetic regulations play critical roles in HNSC tumorigenesis, progression, and activation of functional immune cells. This study aims to identify an epigenetic signature as an immunophenotype indicator of durable clinical immunotherapeutic benefits in HNSC patients.

METHODS

Unsupervised consensus clustering approach was applied to distinguish immunophenotypes based on five immune signatures in The Cancer Genome Atlas (TCGA) HNSC cohort. Two immunophenotypes (immune 'Hot' and immune 'Cold') that had different TME features, diverse prognosis, and distinct DNA methylation patterns were recognized. Immunophenotype-related methylated signatures (IPMS) were identified by the least absolute shrinkage and selector operation algorithm. Additionally, the IPMS score by deconvolution algorithm was constructed as an immunophenotype classifier to predict clinical outcomes and immunotherapeutic response.

RESULTS

The 'Hot' HNSC immunophenotype had higher immunoactivity and better overall survival (p = 0.00055) compared to the 'Cold' tumors. The immunophenotypes had distinct DNA methylation patterns, which was closely associated with HNSC tumorigenesis and functional immune cell infiltration. 311 immunophenotype-related methylated CpG sites (IRMCs) was identified from TCGA-HNSC dataset. IPMS score model achieved a strong clinical predictive performance for classifying immunophenotypes. The area under the curve value (AUC) of the IPMS score model reached 85.9% and 89.8% in TCGA train and test datasets, respectively, and robustness was verified in five HNSC validation datasets. It was also validated as an immunophenotype classifier for predicting durable clinical benefits (DCB) in lung cancer patients who received anti-PD-1/PD-L1 immunotherapy (p = 0.017) and TCGA-SKCM patients who received distinct immunotherapy (p = 0.033).

CONCLUSIONS

This study systematically analyzed DNA methylation patterns in distinct immunophenotypes to identify IPMS with clinical prognostic potential for personalized epigenetic anticancer approaches in HNSC patients. The IPMS score model may serve as a reliable epigenome prognostic tool for clinical immunophenotyping to guide immunotherapeutic strategies in HNSC.

Lidocaine induces apoptosis in head and neck squamous cell carcinoma through activation of bitter taste receptor T2R14

Head and neck squamous cell carcinomas (HNSCCs) have high mortality and significant treatment-related morbidity. It is vital to discover effective, minimally invasive therapies that improve survival and quality of life. Bitter taste receptors (T2Rs) are expressed in HNSCCs, and T2R activation can induce apoptosis. Lidocaine is a local anesthetic that also activates bitter taste receptor 14 (T2R14). Lidocaine has some anti-cancer effects, but the mechanisms are unclear. Here, we find that lidocaine causes intracellular Ca2+ mobilization through activation of T2R14 in HNSCC cells. T2R14 activation with lidocaine depolarizes mitochondria, inhibits proliferation, and induces apoptosis. Concomitant with mitochondrial Ca2+ influx, ROS production causes T2R14-dependent accumulation of poly-ubiquitinated proteins, suggesting that proteasome inhibition contributes to T2R14-induced apoptosis. Lidocaine may have therapeutic potential in HNSCCs as a topical gel or intratumor injection. In addition, we find that HPV-associated (HPV+) HNSCCs are associated with increased TAS2R14 expression. Lidocaine treatment may benefit these patients, warranting future clinical studies.

Diffusion MRI correlation with p16 status and prediction for tumor progression in locally advanced head and neck cancer

Purpose

To investigate p16 effects on diffusion image metrics and associations with tumor progression in patients with locally advanced head and neck cancers.

Methods

Diffusion images pretreatment and after 20 Gy (2wk) of RT were analyzed in patients with cT4/N3 p16+ oropharynx cancer (OPSCC) (N=51) and locoregionally advanced head and neck squamous cell carcinoma (LAHNSCC) (N=28), enrolled onto a prospective adaptive RT trial. Mean ADC values, subvolumes with ADC <1.2 um2/ms (TVLADC), and peak values of low (µL) and high (µH) components of ADC histograms in primary and total nodal gross tumor volumes were analyzed for prediction of freedom from local, distant, or any progression (FFLP, FFDP or FFLRDP) using multivariate Cox proportional-hazards model with clinical factors. P value with false discovery control <0.05 was considered as significant.

Results

With a mean follow up of 36 months, 18 of LAHNSCC patients and 16 of p16+ OPSCC patients had progression. After adjusting for p16, small µL and ADC values, and large TVLADC of primary tumors pre-RT were significantly associated with superior FFLRDP, FFLP and FFDP in the LAHNSCC (p<0.05), but no diffusion metrics were significant in p16+ oropharynx cancers. Post ad hoc analysis of the p16+ OPSCC only showed that large TVLADC of the total nodal burden pre-RT was significantly associated with inferior FFDP (p=0.05).

Conclusion

ADC metrics were associated with different progression patterns in the LAHNSCC and p16+ OPSCC, possibly explained by differences in cancer biology and morphology. A deep understanding of ADC metrics is warranted to establish imaging biomarkers for adaptive RT in HNSCC.

HPV-Negative and HPV-Positive Oral Cancer Cells Stimulate the Polarization of Neutrophils towards Different Functional Phenotypes In Vitro

High-risk human papillomavirus (HPV) infection is one of the leading causes of oropharyngeal squamous cell carcinoma (OPSCC), while the correlation between HPV and oral squamous cell carcinoma (OSCC) remains controversial. The inflammatory infiltrate involved in these epithelial neoplasms differs based on their association with HPV. HPV- tumors show higher tumor-associated neutrophil (TAN) infiltration. It is believed that TANs can play a dual role in cancer by exerting either anti-tumorigenic or pro-tumorigenic effects. However, the impact of HPV status on neutrophil polarization remains unknown. Therefore, this study aimed to investigate the effect of OSCC cells, both HPV- and HPV16+, on the functional phenotype of neutrophils. Peripheral blood neutrophils were stimulated with supernatants from OSCC cell lines and non-tumorigenic HaCaT keratinocytes transduced with HPV16 E6/E7 oncogenes. Subsequently, cytokine production, cell viability, metabolism, expression of degranulation markers, and PD-L1 expression were evaluated. Our findings demonstrate that in contrast to UPCI:SCC154 (HPV+ OSCC) cells, the SCC-9 (HPV- OSCC) cell line induced a highly activated functional state in neutrophils, which is potentially associated with a pro-tumorigenic effect. The HaCaT 16-E7 supernatant only stimulated the activation of some neutrophil functions. Understanding the complex interplay between neutrophils and their microenvironment has the potential to identify TANs as viable therapeutic targets.

Novel Immunotherapeutic Approaches to Treating HPV-Related Head and Neck Cancer

Head and neck cancer (HNC) is the seventh most common malignancy, with oropharyngeal squamous cell carcinoma (OPSCC) accounting for a majority of cases in the western world. While HNC accounts for only 5% of all cancers in the United States, the incidence of a subset of OPSCC caused by human papillomavirus (HPV) is increasing rapidly. The treatment for OPSCC is multifaceted, with a recently emerging focus on immunotherapeutic approaches. With the increased incidence of HPV-related OPSCC and the approval of immunotherapy in the management of recurrent and metastatic HNC, there has been rising interest in exploring the role of immunotherapy in the treatment of HPV-related OPSCC specifically. The immune microenvironment in HPV-related disease is distinct from that in HPV-negative OPSCC, which has prompted further research into various immunotherapeutics. This review focuses on HPV-related OPSCC, its immune characteristics, and current challenges and future opportunities for immunotherapeutic applications in this virus-driven cancer.

The role of HPV status in patients with overlapping grey zone cancer in oral cavity and oropharynx

PURPOSE

We aimed to explore the clinicodemographic characteristics and prognosis of grey zone squamous cell cancer (GZSCC) located in the overlapping or ambiguous area of oral cavity and oropharynx and to identify valuable factors that would improve its differential diagnosis and prognosis.

METHODS

Information of GZSCC patients in the Surveillance, Epidemiology, and End Results (SEER) database were compared to patients with oral cavity (OCSCC) and oropharyngeal (OPSCC) squamous cell carcinomas with corresponding HPV status, respectively. Kaplan-Meier method with log-rank test and multivariate Cox regression analysis were applied to assess associations between clinical characteristics and overall survival (OS). A predictive model integrating age, gender, marital status, HPV status and staging variables was conducted to classify GZSCC patients into three risk groups and verified internally by tenfold cross validation.

RESULTS

A total of 3318 GZSCC, 10792 OPSCC and 6656 OCSCC patients were identified. HPV-positive GZSCC patients had the best 5-year OS as HPV-positive OPSCC (81% vs. 82%). However, the 5-year OS of HPV-negative/unknown GZSCC (43%/42%) were the worst among all groups, indicating that HPV status and the overlapping nature of tumors were valuable prognostic predictors in GZSCC patients. Compared with the strategy of dividing GZSCC into two groups by HPV status, the predictive model integrating more variables could additionally identify a unique high-risk GZSCC group with the lowest OS rate.

CONCLUSIONS

GZSCC patients had distinct clinical characteristics and prognosis compared with OPSCC and OCSCC, integrating HPV status and other clinical factors could help distinguish GZSCC and predict their prognosis.

CD161 Characterizes an Inflamed Subset of Cytotoxic T Lymphocytes Associated with Prolonged Survival in Human Papillomavirus-Driven Oropharyngeal Cancer

Human papillomavirus (HPV)-driven oropharyngeal carcinoma (OPSCC) is distinct from tobacco- or alcohol-associated OPSCC and has a unique immune landscape. Studies have supported the heterogeneity of T cells, accompanied by a broad repertoire of T-cell responses, within tumors driven by HPV infection. However, the phenotype and function of these HPV-related T cells remain unclear. Using a combination of single-cell RNA sequencing, flow cytometry, pharmacologic inhibition, and immunofluorescence staining, we explored the prognostic implication of HPV-related T cells and further validated our findings in two independent cohorts. Cytotoxic T lymphocytes (CTL) within OPSCC displayed a spectrum of transcriptional signatures. Among which, we identified CD161 receptor, encoded by KLRB1, as a potential marker to distinguish the CTL subsets in HPV-positive OPSCC with a divergent evolutionary trajectory. In-depth analysis revealed that CD161+ CTLs exhibited a more robust immune response over the CD161- counterparts and a T cell-inflamed phenotype that could be further reinvigorated by immune-checkpoint blockade. Despite the high expression of exhaustion markers, reinforcement of CD161+ CTL reactivity was expected to boost immune responses, considering their functional reversibility. We further confirmed that the high level of intratumoral CD161+ CTLs associated with a favorable treatment response and prolonged overall survival. Therefore, our research not only provides an insight into the immune landscape of HPV-driven OPSCC but also sheds light on a special subset of CTLs with prognostic and therapeutic significance.

Transcriptional analysis links B cells and TERT expression to favorable prognosis in head and neck cancer

Telomerase reverse transcriptase (TERT) is a conserved self-tumor antigen overexpressed in ∼85% of tumor cells and is immunogenic in cancer patients. The effect of TERT expression on the regulation of intratumor adaptive immunity has not yet been investigated. We used RNA sequencing data from The Cancer Genome Atlas (TCGA) in 11 solid tumor types to investigate potential interactions between TERT expression, and B and T cell infiltrate in the tumor microenvironment. We found a positive correlation between TERT expression, B and T cells in four cancer types with the strongest association in head and neck squamous cell carcinoma (HSNCC). In HNSCC a Bhigh/TERThigh signature was associated with improved progression-free survival (PFS) (P = 0.0048). This effect was independent of HPV status and not shared in comparable analysis by other conserved tumor antigens (NYESO1, MUC1, MAGE, and CEA). Bhigh/TERThigh HNSCC tumors also harbored evidence of tertiary lymphoid structure (TLS) such as signatures for germinal center (GC) and switched memory B cells, central memory CD4 and effector memory CD8 T cells. Bhigh/TERThigh HNSCC tumors also showed an up-regulation of genes and pathways related to B and T cell activation, proliferation, migration, and cytotoxicity, while factors associated with immunosuppression and cancer cell invasiveness were down-regulated. In summary, our study uncovers a new association between high TERT expression and high B cell infiltrate in HNSCC, suggesting a potential benefit from therapeutic strategies that invigorate intratumor TERT-mediated T-B cooperation.

How Risk Factors Affect Head and Neck Squamous Cell Carcinoma (HNSCC) Tumor Immune Microenvironment (TIME): Their Influence on Immune Escape Mechanisms and Immunotherapy Strategy

Most head and neck squamous cell carcinomas (HNSCCs) are caused by lifestyle, such as cigarette smoking, or by viruses, such as human papillomavirus (HPV) and Epstein–Barr virus (EBV). HNSCC remains a clinical challenge, notwithstanding the improvements observed in the past years, involving surgery, radiotherapy, and chemotherapy. Recurrent/metastatic (R/M) disease represents an unmet clinical need. Immunotherapy has improved the prognosis of a small proportion of these patients, but most still do not benefit. In the last decade, several preclinical and clinical studies have explored the HNSCC tumor immune microenvironment (TIME), identifying important differences between smoking-associated and virus-associated HNSCCs. This review aims to present how different etiologies affect the HNSCC TIME, affecting immune escape mechanisms and sensitivity to immunotherapy.

HPV E6 regulates therapy responses in oropharyngeal cancer by repressing the PGC-1α/ERRα axis

Therapy with radiation plus cisplatin kills HPV+ oropharyngeal squamous cell carcinomas (OPSCCs) by increasing reactive oxygen species beyond cellular antioxidant capacity. To explore why these standard treatments fail for some patients, we evaluated whether the variation in HPV oncoprotein levels among HPV+ OPSCCs affects mitochondrial metabolism, a source of antioxidant capacity. In cell line and patient-derived xenograft models, levels of HPV full-length E6 (fl-E6) inversely correlated with oxidative phosphorylation, antioxidant capacity, and therapy resistance, and fl-E6 was the only HPV oncoprotein to display such correlations. Ectopically expressing fl-E6 in models with low baseline levels reduced mitochondrial mass, depleted antioxidant capacity, and sensitized to therapy. In this setting, fl-E6 repressed the peroxisome proliferator-activated receptor gamma co-activator 1α/estrogen-related receptor α (PGC-1α/ERRα) pathway for mitochondrial biogenesis by reducing p53-dependent PGC-1α transcription. Concordant observations were made in 3 clinical cohorts, where expression of mitochondrial components was higher in tumors of patients with reduced survival. These tumors contained the lowest fl-E6 levels, the highest p53 target gene expression, and an activated PGC-1α/ERRα pathway. Our findings demonstrate that E6 can potentiate treatment responses by depleting mitochondrial antioxidant capacity and provide evidence for low E6 negatively affecting patient survival. E6's interaction with the PGC-1α/ERRα axis has implications for predicting and targeting treatment resistance in OPSCC.

Low expression of TMPRSS2–a SARS-CoV-2 internalization protease–associates with basal subtype of head and neck squamous cell carcinoma

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ACE2 and TMPRSS2, which are utilized for the COVID-19 entry into human cells, are expressed throughout the head and neck tissues.

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Different subtypes of HNSCC patients have different expression pattern of genes utilized by the COVID-19 to enter human cells.

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HPV-negative HNSCC patients have significantly lower expression of TMPRSS2 while significantly higher expression of ACE2 and FURIN.

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The basal subtype of HNSCC patients show significantly lower expression of TMPRSS2 but significantly higher expression of FURIN.

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We predict that the HNSCC patients of the basal subtype would be less susceptible to COVID-19 infection compared to the patients of other subtypes.

SARS-CoV-2 is a single-stranded RNA virus that has caused the ongoing COVID-19 pandemic. ACE2 and other genes utilized by SARS-CoV-2 to enter human cells have been shown to express in Head and Neck Squamous Cell Carcinoma (HNSCC) patients. However, their expression pattern in different subtypes has not been investigated. Hence, in the current study, we have analyzed the expression of ACE2, TMPRSS2 and FURIN in 649 HNSCC patients from two independent cohorts. Our analysis showed significantly lower expression of TMPRSS2 while significantly increased expression of ACE2 and FURIN in HPV-negative HNSCC. Comparison of expression of these genes in the three subtypes of HNSCC patients (basal, classical and inflamed/mesenchymal) showed no significant difference in the expression of ACE2 among the three subtypes; however, the basal subtype showed significantly reduced expression of TMPRSS2 but significantly increased expression of FURIN. Comparison of expression of these genes between the HPV-negative patients of basal subtype vs all others confirmed significantly lower expression of TMPRSS2 in HPV-negative patients of basal subtype as compared to all others. Our study shows that the different subtypes of HNSCC patients have different expression patterns of genes utilized by the SARS-CoV-2 to enter human cells, and hence, their susceptibility to SARS-CoV-2 may also be different. As the expression of TMPRSS2 is significantly lower in the HNSCC patients of the basal subtype, we predict that these patients would be less susceptible to SARS-CoV-2 infection than the patients of other subtypes. However, these findings need to be further validated.

The association between inflammatory biomarkers and statin use among patients with head and neck squamous cell carcinoma

BACKGROUND

Tumor-infiltrating lymphocytes (TILs) and cytokines are associated with prognosis among patients with head and neck squamous cell carcinoma (HNSCC). Statins (cholesterol-lowering drugs) may improve HNSCC prognosis, particularly in human papillomavirus (HPV)-positive cases, but the mechanism remains unclear.

METHODS

Statin use was collected from medical records for HNSCC cases (2008-2014). TILs were counted in tumor tissue, and a total weighted score (TILws) was created. Cytokines were measured in blood. The associations between statins and biomarkers were estimated using logistic (biomarker categories: <median, ≥median) and linear regression models (log-transformed continuous biomarkers) adjusted for age, smoking, and comorbidities.

RESULTS

We observed a positive association between statins and TILs among HPV-positive patients (TILws odds ratio [OR] = 2.80; 95% CI = 1.03-7.61), but no association among HPV-negative patients. We observed no association between statins and cytokines.

CONCLUSIONS

Statins may influence TILs in HPV-positive patients. This may be the mechanism through which they improve prognosis in HPV-positive HNSCC patients.

Non-homologous dsODN increases the mutagenic effects of CRISPR-Cas9 to disrupt oncogene E7 in HPV positive cells

Genome editing tools targeting high-risk human papillomavirus (HPV) oncogene could be a promising therapeutic strategy for the treatment of HPV-related cervical cancer. We aimed to improve the editing efficiency and detect off-target effects concurrently for the clinical translation strategy by using CRISPR-Cas9 system co-transfected with 34nt non-homologous double-stranded oligodeoxynucleotide (dsODN). We firstly tested this strategy on targeting the Green Fluorescent Protein (GFP) gene, of which the expression is easily observed. Our results showed that the GFP+ cells were significantly decreased when using GFP-sgRNAs with dsODN, compared to using GFP-sgRNAs without donors. By PCR and Sanger sequencing, we verified the dsODN integration into the break sites of the GFP gene. And by amplicon sequencing, we observed that the indels% of the targeted site on the GFP gene was increased by using GFP-sgRNAs with dsODN. Next, we went on to target the HPV18 E7 oncogene by using single E7-sgRNA and multiplexed E7-sgRNAs respectively. Whenever using single sgRNA or multiplexed sgRNAs, the mRNA expression of HPV18 E7 oncogene was significantly decreased when adding E7-sgRNAs with dsODN, compared to E7-sgRNAs without donor. And the indels% of the targeted sites on the HPV18 E7 gene was markedly increased by adding dsODN with E7-sgRNAs. Finally, we performed GUIDE-Seq to verify that the integrated dsODN could serve as the marker to detect off-target effects in using single or multiplexed two sgRNAs. And we detected fewer on-target reads and off-target sites in multiplexes compared to the single sgRNAs when targeting the GFP and the HPV18 E7 genes. Together, CRISPR-Cas9 system co-transfected with 34nt dsODN concurrently improved the editing efficiency and monitored off-target effects, which might provide new insights in the treatment of HPV infections and related cervical cancer.

HPV16 and HPV18 Genome Structure, Expression, and Post-Transcriptional Regulation

Human papillomaviruses (HPV) are a group of small non-enveloped DNA viruses whose infection causes benign tumors or cancers. HPV16 and HPV18, the two most common high-risk HPVs, are responsible for ~70% of all HPV-related cervical cancers and head and neck cancers. The expression of the HPV genome is highly dependent on cell differentiation and is strictly regulated at the transcriptional and post-transcriptional levels. Both HPV early and late transcripts differentially expressed in the infected cells are intron-containing bicistronic or polycistronic RNAs bearing more than one open reading frame (ORF), because of usage of alternative viral promoters and two alternative viral RNA polyadenylation signals. Papillomaviruses proficiently engage alternative RNA splicing to express individual ORFs from the bicistronic or polycistronic RNA transcripts. In this review, we discuss the genome structures and the updated transcription maps of HPV16 and HPV18, and the latest research advances in understanding RNA cis-elements, intron branch point sequences, and RNA-binding proteins in the regulation of viral RNA processing. Moreover, we briefly discuss the epigenetic modifications, including DNA methylation and possible APOBEC-mediated genome editing in HPV infections and carcinogenesis.

Subclass-specific Prognosis and Treatment Efficacy Inference in Head and Neck Squamous Carcinoma

Exploring the prognostic classification and biomarkers in Head and Neck Squamous Carcinoma (HNSC) is of great clinical significance. We hybridized three prominent strategies to comprehensively characterize the molecular features of HNSC. We constructed a 15-gene signature to predict patients death risk with an average AUC of 0.744 for 1-, 3-, and 5-year on TCGA-HNSC training set, and average AUCs of 0.636, 0.584, 0.755 in GSE65858, GSE-112026, CPTAC-HNSCC datasets, respectively. By combined with NMF clustering and consensus clustering of fraction of tumor immune cell infiltration (ICI) in the tumor microenvironment (TME), we captured a more refined biological characteristics of HNSC, and observed a prognosis heterogeneity in high tumor immunity patients. By matching tumor subset-specific expression signatures to drug-induced cell line expression profiles from large-scale pharmacogenomic databases in the OCTAD workspace, we identified a group of HNSC patients featured with poor prognosis and demonstrated that the individuals in this group are likely to receive increased drug sensitivity to reverse differentially expressed disease signature genes. This trend is especially highlighted among those with higher death risk and tumour immunity.

YAP1 activation by human papillomavirus E7 promotes basal cell identity in squamous epithelia

Persistent human papillomavirus (HPV) infection of stratified squamous epithelial cells causes nearly 5% of cancer cases worldwide. HPV-positive oropharyngeal cancers harbor few mutations in the Hippo signaling pathway compared to HPV-negative cancers at the same anatomical site, prompting the hypothesis that an HPV-encoded protein inactivates the Hippo pathway and activates the Hippo effector yes-associated protein (YAP1). The HPV E7 oncoprotein is required for HPV infection and for HPV-mediated oncogenic transformation. We investigated the effects of HPV oncoproteins on YAP1 and found that E7 activates YAP1, promoting YAP1 nuclear localization in basal epithelial cells. YAP1 activation by HPV E7 required that E7 binds and degrades the tumor suppressor protein tyrosine phosphatase non-receptor type 14 (PTPN14). E7 required YAP1 transcriptional activity to extend the lifespan of primary keratinocytes, indicating that YAP1 activation contributes to E7 carcinogenic activity. Maintaining infection in basal cells is critical for HPV persistence, and here we demonstrate that YAP1 activation causes HPV E7 expressing cells to be retained in the basal compartment of stratified epithelia. We propose that YAP1 activation resulting from PTPN14 inactivation is an essential, targetable activity of the HPV E7 oncoprotein relevant to HPV infection and carcinogenesis.

The ‘epithelial’ cells that cover our bodies are in a constant state of turnover. Every few weeks, the outermost layers die and are replaced by new cells from the layers below. For scientists, this raises a difficult question. Cells infected by human papillomaviruses, often known as HPV, can become cancerous over years or even decades. How do infected cells survive while the healthy cells around them mature and get replaced?

One clue could lie in PTPN14, a human protein which many papillomaviruses eliminate using their viral E7 protein; this mechanism could be essential for the virus to replicate and cause cancer. To find out the impact of losing PTPN14, Hatterschide et al. used human epithelial cells to make three-dimensional models of infected tissues. These experiments showed that, when papillomaviruses destroy PTPN14, a human protein called YAP1 turns on in the lowest, most long-lived layer of the tissue. Cells in which YAP1 is activated survive while those that carry the inactive version mature and die. This suggests that papillomaviruses turn on YAP1 to remain in tissues for long periods.

Papillomaviruses cause about five percent of all human cancers. Finding ways to stop them from activating YAP1 has the potential to prevent disease. Overall, the research by Hatterschide et al. also sheds light on other epithelial cancers which are not caused by viruses.

HPV-associated oropharyngeal cancer: epidemiology, molecular biology and clinical management

Human papillomavirus (HPV)-positive (HPV⁺) oropharyngeal squamous cell carcinoma (OPSCC) has one of the most rapidly increasing incidences of any cancer in high-income countries. The most recent (8th) edition of the UICC/AJCC staging system separates HPV⁺ OPSCC from its HPV-negative (HPV⁻) counterpart to account for the improved prognosis seen in the former. Indeed, owing to its improved prognosis and greater prevalence in younger individuals, numerous ongoing trials are examining the potential for treatment de-intensification as a means to improve quality of life while maintaining acceptable survival outcomes. In addition, owing to the distinct biology of HPV⁺ OPSCCs, targeted therapies and immunotherapies have become an area of particular interest. Importantly, OPSCC is often detected at an advanced stage owing to a lack of symptoms in the early stages; therefore, a need exists to identify and validate possible diagnostic biomarkers to aid in earlier detection. In this Review, we provide a summary of the epidemiology, molecular biology and clinical management of HPV⁺ OPSCC in an effort to highlight important advances in the field. Ultimately, a need exists for improved understanding of the molecular basis and clinical course of this disease to guide efforts towards early detection and precision care, and to improve patient outcomes.

The incidence of human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) is increasing rapidly in most developed countries. In this Review, the authors provide an overview of the epidemiology, molecular biology and treatment of HPV-positive OPSCC, including discussions of the role of treatment de-escalation and emerging novel therapies.

The incidence of human papillomavirus-associated oropharyngeal cancer (HPV⁺ OPSCC) is expected to continue to rise over the coming decades until the benefits of gender-neutral prophylactic HPV vaccination begin to become manifest.

The incidence of HPV⁺ OPSCC appears to be highest in high-income countries, although more epidemiological data are needed from low- and middle-income countries, in which HPV vaccination coverage remains low.

The substantially better prognosis of patients with HPV⁺ OPSCC compared to those with HPV^– OPSCC has been recognized in the American Joint Committee on Cancer TNM8 staging guidelines, which recommend stratification by HPV status to improve staging.

The molecular biology and genomic features of HPV⁺ OPSCC are similar to those of other HPV-associated malignancies, with HPV oncogenes (E6 and E7) acting as key drivers of pathogenesis.

Treatment de-intensification is being pursued in clinical trials, although identifying the ~15% of patients with HPV⁺ OPSCC who have recurrent disease, and who therefore require more intensive treatment, remains a key challenge.

Immunotherapy Approaches in HPV-Associated Head and Neck Cancer

Immunotherapy approaches for head and neck squamous cell carcinoma (HNSCC) are rapidly advancing. Human papillomavirus (HPV) has been identified as a causative agent in a subset of oropharyngeal cancers (OPC). HPV-positive OPC comprises a distinct clinical and pathologic disease entity and has a unique immunophenotype. Immunotherapy with anti-PD1 checkpoint inhibitors has exhibited improved outcomes for patients with advanced HNSCC, irrespective of HPV status. To date, the clinical management of HPV-positive HNSCC and HPV-negative HNSCC has been identical, despite differences in the tumor antigens, immune microenvironment, and immune signatures of these two biologically distinct tumor types. Numerous clinical trials are underway to further refine the application of immunotherapy and develop new immunotherapy approaches. The aim of this review is to highlight the developing role of immunotherapy in HPV-positive HNSCC along with the clinical evidence and preclinical scientific rationale behind emerging therapeutic approaches, with emphasis on promising HPV-specific immune activators that exploit the universal presence of foreign, non-self tumor antigens.

Association of Tumor Site With the Prognosis and Immunogenomic Landscape of Human Papillomavirus-Related Head and Neck and Cervical Cancers

Importance

Human papillomavirus (HPV)-positive status in patients with oropharyngeal squamous cell carcinoma (OPSCC) is associated with improved survival compared with HPV-negative status. However, it remains controversial whether HPV is associated with improved survival among patients with nonoropharyngeal and cervical squamous cell tumors.

Objective

To investigate differences in the immunogenomic landscapes of HPV-associated tumors across anatomical sites (the head and neck and the cervix) and their association with survival.

Design, Setting, and Participants

This cohort study used genomic and transcriptomic data from the Cancer Genome Atlas (TCGA) for 79 patients with OPSCC, 435 with nonoropharyngeal head and neck squamous cell carcinoma (non-OP HNSCC), and 254 with cervical squamous cell carcinoma and/or endocervical adenocarcinoma (CESC) along with matched clinical data from TCGA. The data were analyzed from November 2020 to March 2021.

Main Outcomes and Measures

Positivity for HPV was classified by RNA-sequencing reads aligned with the HPV reference genome. Gene expression profiles, immune cell phenotypes, cytolytic activity scores, and overall survival were compared by HPV tumor status across multiple anatomical sites.

Results

The study comprised 768 patients, including 514 (66.9%) with HNSCC (380 male [73.9%]; mean [SD] age, 59.5 [10.8] years) and 254 (33.1%) with CESC (mean [SD] age, 48.7 [14.1] years). Human papillomavirus positivity was associated with a statistically significant improvement in overall survival for patients with OPSCC (adjusted hazard ratio [aHR], 0.06; 95% CI, 0.02-0.17; P < .001) but not for those with non-OP HNSCC (aHR, 0.64; 95% CI, 0.31-1.27; P = .20) or CESC (aHR, 0.50; 95% CI, 0.15-1.67; P = .30). The HPV-positive OPSCCs had increased tumor immune infiltration and immunomodulatory receptor expression compared with HPV-negative OPSCCs. Compared with HPV-positive non-OP HNSCCs, HPV-positive OPSCCs showed greater expression of immune-related metrics including B cells, T cells, CD8+ T cells, T-cell receptor diversity, B-cell receptor diversity, and cytolytic activity scores, independent of tumor variant burden. The immune-related metrics were similar when comparing HPV-positive non-OP HNSCCs and HPV-positive CESCs with their HPV-negative counterparts. The 2-year overall survival rate was significantly higher for patients with HPV-positive OPSCC compared with patients with HPV-negative OPSCC (92.0% [95% CI, 84.8%-99.9%] vs 45.8% [95% CI, 28.3%-74.1%]; HR, 0.10 [95% CI, 0.03-0.30]; P = .009).

Conclusions and Relevance

In this cohort study, tumor site was associated with the immune landscape and survival among patients with HPV-related tumors despite presumed similar biologic characteristics. These tumor site-related findings provide insight on possible outcomes of HPV positivity for tumors in oropharyngeal and nonoropharyngeal sites and a rationale for the stratification of HPV-associated tumors by site and the subsequent development of strategies targeting immune exclusion in HPV-positive nonoropharyngeal cancer.

Prevalence of HPV in Mexican Patients with Head and Neck Squamous Carcinoma and Identification of Potential Prognostic Biomarkers

Simple Summary

Head and neck squamous cell carcinomas (HNSCC) are a heterogeneous group of neoplasms that show diverse clinical and biological characteristics associated with human papillomavirus (HPV). Biological and clinical characterization is essential to stratify patients based on prognostic and predictive factors. The biological features of HNSCC may change according to geography and population characteristics. Studies on the molecular biology of HNSCC in Mexico are scarce. In the present study, we analyzed 414 Mexican patients with HNSCC and determined the presence and genotype of HPV, p16 expression, and global gene expression profiles. Twenty-two percent of total cases were HPV+, and 32% were p16+. We identified genes associated with survival, such as SLIRP, KLF10, AREG, ACT1, and LIMA. In addition, CSF1R, MYC, and SRC genes were identified as potential therapeutic targets. This study offers information that may be relevant for our understanding of the biology of HNSCC and the development of therapeutic strategies.

Abstract

Head and neck squamous cell carcinomas (HNSCC) show a variety of biological and clinical characteristics that could depend on the association with the human papillomavirus (HPV). Biological and clinical characterization is essential to stratify patients based on prognostic and predictive factors. Reports on HNSCC are scarce in Mexico. Herein, we analyzed 414 Mexican patients with HNSCC, including oropharynx (OPSCC), larynx (LASCC), and oral cavity (OCSCC), and identified HPV DNA and p16 expression. Global gene expression profiles were analyzed in 25 HPV+/p16+ vs. HPV−/p16− cases. We found 32.3% p16+ and 22.3% HPV+ samples, HPV 16, 18, 39, 52, and 31 being the most frequent genotypes. For OPSCC, LASCC and OCSCC, 39.2, 14.7, and 9.6% were HPV+/p16+, respectively. High expression of SLIRP, KLF10, AREG, and LIMA was associated with poor survival; in contrast, high expression of MYB and SYCP2 correlated with better survival. In HPV+ cases, high expression of SLC25A39 and GJB2 was associated with poor survival. Likewise, EGFR, IL-1, IL-6, JAK-STAT, WNT, NOTCH, and ESR1 signaling pathways were downregulated in HPV+ cases. CSF1R, MYC, and SRC genes were identified as key hubs and therapeutic targets. Our study offers information regarding the molecular and clinical characteristics of HNSCC in Mexican patients.

T2R bitter taste receptors regulate apoptosis and may be associated with survival in head and neck squamous cell carcinoma

Better management of head and neck squamous cell carcinomas (HNSCCs) requires a clearer understanding of tumor biology and disease risk. Bitter taste receptors (T2Rs) have been studied in several cancers, including thyroid, salivary, and GI, but their role in HNSCC has not been explored. We found that HNSCC patient samples and cell lines expressed functional T2Rs on both the cell and nuclear membranes. Bitter compounds, including bacterial metabolites, activated T2R‐mediated nuclear Ca²⁺ responses leading to mitochondrial depolarization, caspase activation, and ultimately apoptosis. Buffering nuclear Ca²⁺ elevation blocked caspase activation. Furthermore, increased expression of T2Rs in HNSCCs from The Cancer Genome Atlas is associated with improved overall survival. This work suggests that T2Rs are potential biomarkers to predict outcomes and guide treatment selection, may be leveraged as therapeutic targets to stimulate tumor apoptosis, and may mediate tumor‐microbiome crosstalk in HNSCC.

Impact of human papillomavirus on the tumor microenvironment in oropharyngeal squamous cell carcinoma

Increasing evidence has elucidated the clinicopathological significance of tumor microenvironment (TME) cells. However, TME differences associated with human papillomavirus (HPV) infection in oropharyngeal squamous cell carcinoma (OPSCC) have not been well characterized. In our study, we comprehensively determined the TME infiltration patterns in 315 OPSCC patients, and systematically correlated the TME phenotypes with genomic characteristics and clinical features of OPSCCs. In this way, we observed the enrichment of high endothelial cells and adaptive immune cells in HPV-positive (HPV+) OPSCCs, in contrast to the enrichment of fibroblasts and capillary endothelial cells in HPV- negative (HPV-) OPSCCs. By focusing on immune checkpoint genes, we constructed a coexpression network using genes that were differentially expressed between HPV+ and HPV- OPSCCs. Functional analysis of the network indicated that HPV+ OPSCCs had elevated immune activities by promoting adaptive immune response and suppressing activities related to extracellular matrix organization. Subsequently, clinical analysis showed that identified TME-relevant genes were closely associated with the prognosis and therapy response in OPSCC. Importantly, results from the TME analysis were further validated using an independent OPSCC cohort.

Immunotherapy Advances in Locally Advanced and Recurrent/Metastatic Head and Neck Squamous Cell Carcinoma and Its Relationship With Human Papillomavirus

Head and neck cancer (HNC) is the sixth most common malignancy worldwide; head and neck squamous cell carcinoma (HNSCC) account for the most cases of HNC. Past smoking and alcohol consumption are common risk factors of HNSCC; however, an increasing number of cases associated with human papillomavirus (HPV) infection have been reported in recent years. The treatment of HNSCC is integrated and multimodal including traditional surgery, radiotherapy, chemotherapy, and targeted therapy. Since pembrolizumab was approved in 2016, an increasing number of studies have focused on immunotherapy. However, not all of HNSCC patients have a better outcome on immunotherapy. Immunotherapy has been reported to be more effective in HPV-positive patients, but its molecular mechanism is still unclear. Some researchers have proposed that the high proportion of infiltrating immune cells in HPV-positive tumors and the difference in immune checkpoint expression level may be the reasons for their better response. As a result, a series of individualized immunotherapy trials have also been conducted in HPV-positive patients. This paper summarizes the current status of HNSCC immunotherapy, individualized immunotherapy in HPV-positive patients, and immune differences in HPV-positive tumors to provide new insights into HNSCC immunotherapy and try to identify patients who may benefit from immunotherapy.

Prognostic significance of human papillomavirus status and treatment modality in hypopharyngeal cancer

BACKGROUND

Management of hypopharynx cancer is often extrapolated from larynx cancer. This report analyses treatment patterns and survival limited to hypopharynx cancer using the National Cancer Database (NCDB).

METHODS

There are 9314 patients diagnosed with hypopharynx cancer between 2004 and 2016. The association between treatment modality and survival was analyzed using Kaplan-Meier survival curves and multivariable Cox regression.

RESULTS

Five-year overall survival ranged from 45% for stage I to 21% for stage IVB. Treatment modality did not influence survival in stage I/II. For stage III/IV, chemoradiation and surgery + adjuvant therapy were equivalent. Surgery yielded improved survival for T4 disease. Human papillomavirus (HPV)-positive tumors were present in 21% and were associated with improved hazard ratio of death (0.60, p = <0.0001).

CONCLUSIONS

Survival is superior for T4 hypopharynx cancer managed with surgery, while treatment modality does not impact outcomes for other T-stages. HPV-positive tumors are associated with improved survival regardless of treatment.

A MicroRNA Expression Signature as Prognostic Marker for Oropharyngeal Squamous Cell Carcinoma

BACKGROUND

Improved prognostication of oropharyngeal squamous cell carcinoma (OPSCC) may facilitate individualized patient management. The goal of this study was to develop and validate a prognostic signature based on microRNA sequencing (miRNA-seq) analysis.

METHODS

We collected tumor specimens for miRNA-seq analysis from OPSCC patients treated at Washington University in St Louis (n = 324) and Vanderbilt University (n = 130). OPSCC patients (n = 79) from The Cancer Genome Atlas Program were also included for independent validation. Univariate and multivariable Cox regression analyses were performed to identify miRNAs associated with disease outcomes. All statistical tests were 2-sided.

RESULTS

By miRNA-seq profiling analysis, we identified a 26-miRNA signature. Based on computed risk scores of the signature, we classified the patients into low- and high-risk groups. In the training cohort, the high-risk group had much shorter overall survival compared with the low-risk group (hazard ratio [HR] = 3.80, 95% confidence interval [CI] = 2.37 to 6.10, P < .001). Subgroup analysis further revealed that the signature was prognostic for HPV-positive OPSCCs (HR = 3.07, 95% CI = 1.65 to 5.71, P < .001). Multivariable analysis indicated that the signature was independent of common clinicopathologic factors for OPSCCs. Importantly, the miRNA signature was a statistically significant predictor of overall survival in independent validation cohorts (The Cancer Genome Atlas Program cohort: HR = 6.05, 95% CI = 2.10 to 17.37, P < .001; Vanderbilt cohort: HR = 7.98, 95% CI = 3.99 to 15.97, P < .001; Vanderbilt HPV-positive cohort: HR = 8.71, 95% CI = 2.70 to 28.14, P < .001).

CONCLUSIONS

The miRNA signature is a robust and independent prognostic tool for risk stratification of OPSCCs including HPV-positive OPSCCs.

Pathogenic Role of Immune Evasion and Integration of Human Papillomavirus in Oropharyngeal Cancer

The incidence of oropharyngeal cancer (OPC) is increasing remarkably among all head and neck cancers, mainly due to its association with the human papillomavirus (HPV). Most HPVs are eliminated by the host’s immune system; however, because HPV has developed an effective immune evasion mechanism to complete its replication cycle, a small number of HPVs are not eliminated, leading to persistent infection. Moreover, during the oncogenic process, the extrachromosomal HPV genome often becomes integrated into the host genome. Integration involves the induction and high expression of E6 and E7, leading to cell cycle activation and increased genomic instability in the host. Therefore, integration is an important event in oncogenesis, although the associated mechanism remains unclear, especially in HPV-OPC. In this review, we summarize the current knowledge on HPV-mediated carcinogenesis, with special emphasis on immune evasion and integration mechanisms, which are crucial for oncogenesis.

Implementation of Double Immune Checkpoint Blockade Increases Response Rate to Induction Chemotherapy in Head and Neck Cancer

Simple Summary

The study compares the effects on complete remission rate (CR) of a single dose of durvalumab/tremelimumab immediately after a single-cycle platinum and docetaxel as part of induction therapy for a controlled trial in head and neck cancer with chemotherapy alone from a historical collective. The CR rate was 60.3% after induction chemoimmunotherapy (ICIT; induction chemotherapy plus double immune checkpoint blockade) compared with 40.3% after induction chemotherapy (IC) alone. Patients with HPV-positive oropharyngeal cancer may benefit the most from additive double checkpoint inhibition, which is presumably due to the higher amount of infiltrating immune cells. Patients older than 60 years without HPV-positive oropharyngeal cancer are unlikely to benefit.

Abstract

To determine whether a single dose of double immune checkpoint blockade (induction chemoimmunotherapy (ICIT)) adds benefit to induction single-cycle platinum doublet (induction chemotherapy (IC)) in locally advanced head and neck squamous cell carcinoma (HNSCC), patients treated with cisplatin 30 mg/m² d1-3 and docetaxel 75 mg/m² d1 combined with durvalumab 1500 mg fixed dose d5 and tremelimumab 75 mg fixed dose d5 (ICIT) within the CheckRad-CD8 trial were compared with a retrospective cohort receiving the same chemotherapy (IC) without immunotherapy. The endpoint of this analysis was the complete response rate (CR). A total of 53 patients were treated with ICIT and 104 patients with IC only. CR rates were 60.3% for ICIT and 40.3% for IC (p = 0.018). In the total population (n = 157), the most important predictor to achieve a CR was treatment type (OR: 2.21 for ICIT vs. IC; p = 0.038, multivariate analysis). The most diverse effects in CR rates between ICIT and IC were observed in younger (age ≤ 60) patients with HPV-positive OPSCCs (82% vs. 33%, p = 0.176), while there was no difference in older patients without HPV-positive OPSCCs (53% vs. 48%). The analysis provides initial evidence that ICIT could result in higher CR rates than IC. Young patients with HPV-positive OPSCCs may have the greatest benefit from additional immune checkpoint inhibitors.

Factors Affecting Outcomes in Patients With Stage III & IV Squamous Cell Carcinoma of Oropharynx: The Importance of p16 Status, BMI, and Race

Objective

To identify racial disparities in survival outcomes among Stage III & IV patients with squamous cell carcinomas (SCCa) of the oropharynx treated with definitive radiation therapy (RT), with concurrent chemotherapy.

Method

This is a retrospective analysis of patients with stage III & IV SCCa of oropharynx treated with definitive RT at the State Academic Medical Center. All patients were treated to 70 Gy utilizing intensity-modulated radiation treatment (IMRT), and received concurrent chemotherapy with weekly cisplatin or cetuximab. Chi-square test was used to test the goodness of fit, overall survival (OS), and locoregional control (LRC) comparing races were generated by using Log-rank test & Kaplan-Meier method. The covariables associated with the OS and LRC were determined by the Cox regression model. A p-value of less than 0.05 was considered statistically significant. The SPSS 24.0 software (IBM Corp., Armonk, NY) was used.

Results

In the total 73 eligible patients, 54.8% were black, and 45.2% white patients. Stage distribution (per American Joint Committee on Cancer-AJCC 8^th Ed) between black patients vs. white patients, Stage III (45.5% vs. 54.5%) and for Stage IV (56.5% vs. 43.5%); p=0.499. Median follow-up for the entire group was 41 months (range: 4-144 months). In the univariate analysis, variables p16 status, body mass index (BMI), alcohol history and tumor subsite were found to be significant. In the multivariate analysis, only BMI has shown to be significant.

Three-year LRC for black patients was 37.8% vs.66.8% in white patients (p=0.354) and three-year OS for black patients was 51.8% vs. 80.9% for white patients (p=0.063), respectively. Five-year OS for p16 positive patients was 69.7% vs. 43% for p16 negative patients (p=0.034). Five-year OS for Stage IV black patients was 34% vs. 69.5% for Stage IV white patients (p=0.014).

Conclusion

Among all the co-variables examined, only BMI has shown affecting the OS outcomes; gender and BMI shown to be affecting the LRC. Racial factor appears to be significant in Stage IV patients.

Complex Interaction Among Immune, Inflammatory, and Carcinogenic Mechanisms in the Head and Neck Squamous Cell Carcinoma

Inflammation is deeply involved in the development of most types of cancer. Many studies focus on the interaction between immune-inflammatory mechanisms and tumorigenesis in the head and neck squamous cell carcinoma (HNSCC). In this chapter, we emphasize the complexity of processes underlying this interaction and discuss the mechanisms of carcinogenesis in HNSCC with a special focus on metabolic changes, inflammation, and the immune landscape. Unveiling complex connections between immuno-inflammatory processes and tumor initiation, promotion, and progression will open new directions in the reliable identification of predictive factors and therapeutic targets in HNSCC.

Survival Outcomes in Human Papillomavirus-Associated Nonoropharyngeal Squamous Cell Carcinomas: A Systematic Review and Meta-analysis

Importance

Although the survival impact of human papillomavirus (HPV) in oropharyngeal squamous cell carcinoma (OPSCC) is well known, there has been conflicting and scarce evidence on the role of HPV in non-OPSCC.

Objective

To undertake a Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA)-compliant systematic review and meta-analysis of all published studies on the association between HPV status and survival outcomes in patients with non-OPSCC, analyzing each site separately.

Data Sources

PubMed, CINAHL, and Embase were searched from 1946 to December 16, 2019, for English-language articles.

Study Selection

Analysis comprised randomized clinical trials or observational studies that each included at least 10 patients with non-OPSCC in which the presence of HPV was analyzed, survival outcomes were reported, and a clinical follow-up of 1 year or more was performed. Studies excluded were those in which data on OPSCC and non-OPSCC were not distinguished between both cohorts and studies on patients with distant metastatic tumors at diagnosis. Final analysis included outcomes that were analyzed in at least 3 studies.

Data Extraction and Synthesis

Two reviewers independently abstracted the data. Risk of bias was estimated with the Newcastle-Ottawa Scale. Meta-analysis was performed using the random-effects model.

Main Outcomes and Measures

The primary end point was overall survival (OS); secondary end points were disease-specific survival (DSS) and disease-free survival (DFS).

Results

Of the 3947 articles screened, a total of 22 observational and 2 randomized clinical trials were included in the analysis, representing 24 854 patients. In oral cavity locations, OS was not significantly associated with HPV positivity (hazard ratio [HR], 1.16; 95% CI, 0.83-1.61; I2 = 71%); however, HPV-positive tumors showed worse DFS (HR, 1.81; 95% CI, 1.12-2.91; I2 = 47%). Laryngeal and hypopharyngeal HPV-positive tumors were associated with improved OS (HR, 0.71; 95% CI, 0.54-0.92; I2 = 38% and HR, 0.60; 95% CI, 0.47-0.76; I2 = 0%), respectively, whereas, in nasopharyngeal locations HPV was not associated with OS (HR, 0.82; 95% CI, 0.49-1.38; I2 = 46%) or DSS (HR, 0.55; 95% CI, 0.22-1.42; I2 = 65%).

Conclusions and Relevance

In this meta-analysis of 24 studies, HPV was associated with improved OS in laryngeal and hypopharyngeal locations but not in the oral cavity and the nasopharynx. This information may be useful for future clinical studies of laryngeal and hypopharyngeal tumors and whether HPV status should be incorporated in prognostication of patients with these cancers.

Low expression of NSD1, NSD2, and NSD3 define a subset of human papillomavirus-positive oral squamous carcinomas with unfavorable prognosis

Background

Frequent mutations in the nuclear receptor binding SET domain protein 1 (NSD1) gene have been observed in head and neck squamous cell carcinomas (HNSCC). NSD1 encodes a histone 3 lysine-36 methyltransferase. NSD1 mutations are correlated with improved clinical outcomes and increased sensitivity to platinum-based chemotherapy agents in human papillomavirus-negative (HPV-) tumors, despite weak T-cell infiltration. However, the role of NSD1 and related family members NSD2 and NSD3 in human papillomavirus-positive (HPV+) HNSCC is unclear.

Methods

Using data from over 500 HNSCC patients from The Cancer Genome Atlas (TCGA), we compared the relative level of mRNA expression of NSD1, NSD2, and NSD3 in HPV+ and HPV- HNSCC. Correlation analyses were performed between T-cell infiltration and the relative level of expression of NSD1, NSD2, and NSD3 mRNA in HPV+ and HPV- HNSCC. In addition, overall survival outcomes were compared for both the HPV+ and HPV- subsets of patients based on stratification by NSD1, NSD2, and NSD3 expression levels.

Results

Expression levels of NSD1, NSD2 or NSD3 were not correlated with altered lymphocyte infiltration in HPV+ HNSCC. More importantly, low expression of NSD1, NSD2, or NSD3 correlated with significantly reduced overall patient survival in HPV+, but not HPV- HNSCC.

Conclusion

These results starkly illustrate the contrast in molecular features between HPV+ and HPV- HNSCC tumors and suggest that NSD1, NSD2, and NSD3 expression levels should be further investigated as novel clinical metrics for improved prognostication and patient stratification in HPV+ HNSCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13027-021-00347-6.

Increased Abundance of Tumour-Associated Neutrophils in HPV-Negative Compared to HPV-Positive Oropharyngeal Squamous Cell Carcinoma Is Mediated by IL-1R Signalling

The incidence of human papillomavirus (HPV)-associated cancer is increasing and HPV is now implicated in the aetiology of more than 60% of all oropharyngeal squamous cell carcinomas (OPSCC). In OPSCC, innate immune cells such as neutrophils and macrophages generally correlate with poor prognosis, whilst adaptive immune cells, such as lymphocytes, tend to correlate with improved prognosis. This may, in part, be due to differences in the immune response within the tumour microenvironment leading to the recruitment of specific tumour-associated leukocyte sub-populations. In this study, we aimed to examine if differences exist in the levels of infiltrated leukocyte sub-populations, with particular emphasis on tumour-associated neutrophils (TAN), and to determine the mechanism of chemokine-induced leukocyte recruitment in HPV-positive compared to HPV-negative OPSCC. Immunohistochemical analysis showed that HPV-negative OPSCC contained significantly more neutrophils than HPV-positive tumours, whilst levels of CD68+ macrophages and CD3+ lymphocytes were similar. Using a 3D tissue culture model to represent tumour-stromal interactions, we demonstrated that HPV-negative tumour-stromal co-cultures expressed significantly higher levels of CXCL8, leading to increased neutrophil recruitment compared to their HPV-positive counterparts. HPV-negative OPSCC cells have previously been shown to express higher levels of IL-1 than their HPV-positive counterparts, indicating that this cytokine may be responsible for driving increased chemokine production in the HPV-negative 3D model. Inhibition of IL-1R in the tumour-stromal models using the receptor-specific antagonist, anakinra, dramatically reduced chemokine secretion and significantly impaired neutrophil and monocyte recruitment, suggesting that this tumour-stromal response is mediated by the IL-1/IL-1R axis. Here, we identify a mechanism by which HPV-negative OPSCC may recruit more TAN than HPV-positive OPSCC. Since TAN are associated with poor prognosis in OPSCC, our study identifies potential therapeutic targets aimed at redressing the chemokine imbalance to reduce innate immune cell infiltration with the aim of improving patient outcome.

Radiotherapy and Immunotherapy for Head and Neck Cancer: Current Evidence and Challenges

Immune checkpoint inhibitors (ICI) have revolutionized cancer treatment over the past decade. However, although the immune landscape suggests a strong rationale for the use of these agents in patients with head and neck squamous cell carcinoma, the available clinical evidence indicates that most patients currently do not respond to ICI monotherapy. Radiotherapy is a primary treatment modality for many patients with locally advanced head and neck cancer. While ionizing radiation traditionally has been thought to act in a purely cytotoxic fashion, a growing body of preclinical studies have demonstrated additional profound immunomodulatory effects. Consequently, there has been a surge of interest in the potential synergy between radiotherapy and immunotherapy, both the potential for radiotherapy to augment the systemic anti-tumor immune response and the potential for immunotherapy to improve in-field tumor response to radiation. In this review, we summarize the current preclinical and clinical evidence for radioimmunotherapy, with a particular focus on studies directly relevant to head and neck squamous cell carcinoma, as well as existing challenges and future directions for this emerging field.

HPV Meets APOBEC: New Players in Head and Neck Cancer

Besides smoking and alcohol, human papillomavirus (HPV) is a factor promoting head and neck squamous cell carcinoma (HNSCC). In some human tumors, including HNSCC, a number of mutations are caused by aberrantly activated DNA-modifying enzymes, such as the apolipoprotein B mRNA editing enzyme catalytic polypeptide-like (APOBEC) family of cytidine deaminases. As the enzymatic activity of APOBEC proteins contributes to the innate immune response to viruses, including HPV, the role of APOBEC proteins in HPV-driven head and neck carcinogenesis has recently gained increasing attention. Ongoing research efforts take the cue from two key observations: (1) APOBEC expression depends on HPV infection status in HNSCC; and (2) APOBEC activity plays a major role in HPV-positive HNSCC mutagenesis. This review focuses on recent advances on the role of APOBEC proteins in HPV-positive vs. HPV-negative HNSCC.

Correlation of HPV16 Gene Status and Gene Expression With Antibody Seropositivity and TIL Status in OPSCC

INTRODUCTION

Human papillomavirus 16 (HPV16) is the main cause of oropharyngeal squamous cell carcinoma (OPSCC). To date, the links between HPV16 gene expression and adaptive immune responses have not been investigated. We evaluated the correlation of HPV16 DNA, RNA transcripts and features of adaptive immune response by evaluating antibody isotypes against E2, E7 antigens and density of tumor-infiltrating lymphocytes (TIL).

MATERIAL AND METHODS

FFPE-tissue from 27/77 p16-positive OPSCC patients was available. DNA and RNA were extracted and quantified using qPCR for all HPV16 genes. The TIL status was assessed. Immune responses against E2 and E7 were quantified by ELISA (IgG, IgA, and IgM; 77 serum samples pre-treatment, 36 matched post-treatment).

RESULTS

Amounts of HPV16 genes were highly correlated at DNA and RNA levels. RNA co-expression of all genes was detected in 37% (7/19). E7 qPCR results were correlated with higher anti-E7 antibody (IgG, IgA) level in the blood. Patients with high anti-E2 IgG antibody (>median) had better overall survival (p=0.0311); anti-E2 and anti-E7 IgA levels had no detectable effect. During the first 6 months after treatment, IgA but not IgG increased significantly, and >6 months both antibody classes declined over time. Patients with immune cell-rich tumors had higher levels of circulating antibodies against HPV antigens.

CONCLUSION

We describe an HPV16 qPCR assay to quantify genomic and transcriptomic expression and correlate this with serum antibody levels against HPV16 oncoproteins. Understanding DNA/RNA expression, relationship to the antibody response in patients regarding treatment and outcome offers an attractive tool to improve patient care.

The DNA methylation landscape of PD-1 (PDCD1) and adjacent lncRNA AC131097.3 in head and neck squamous cell carcinoma

Aims: PD-1 expression is associated with DNA methylation in head and neck squamous cell carcinomas (HNSCCs). We performed methylation analysis at single CpG site resolution in order to understand epigenetic regulation. Materials and methods: CpG methylation analysis of PD-1 and long non-coding RNA (lncRNA) AC131097.3 was performed in n = 528 HNSCCs and n = 50 normal adjacent tissues provided by The Cancer Genome Atlas and in isolated leukocytes. Results: PD-1 mRNA and AC131097.3 lncRNA expression correlated inversely with promoter and positively with gene body CpG methylation. PD-1 and AC131097.3 are co-expressed. Methylation was sequence-contextually associated with human papillomavirus prognosis, mutational load, and immune infiltrates. Conclusions: The significance of PD-1 and AC131097.3 methylation is highly sequence-contextual. AC131097.3 might play a role in HNSCC.

The interesting relationship between APOBEC3 deoxycytidine deaminases and cancer: a long road ahead

Cancer is considered a group of diseases characterized by uncontrolled growth and spread of abnormal cells and is propelled by somatic mutations. Apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 3 (APOBEC3) family of enzymes are endogenous sources of somatic mutations found in multiple human cancers. While these enzymes normally act as an intrinsic immune defence against viruses, they can also catalyse 'off-target' cytidine deamination in genomic single-stranded DNA intermediates. The deamination of cytosine forms uracil, which is promutagenic in DNA. Key factors to trigger the APOBEC 'off-target' activity are overexpression in a non-normal cell type, nuclear localization and replication stress. The resulting uracil-induced mutations contribute to genomic variation, which may result in neutral, beneficial or harmful consequences for the cancer. This review summarizes the functional and biochemical basis of the APOBEC3 enzyme activity and highlights their relationship with the most well-studied cancers in this particular context such as breast, lung, bladder, and human papillomavirus-associated cancers. We focus on APOBEC3A, APOBEC3B and APOBEC3H haplotype I because they are the leading candidates as sources of somatic mutations in these and other cancers. Also, we discuss the prognostic value of the APOBEC3 expression in drug resistance and response to therapies.

AKR1C3 is a biomarker and druggable target for oropharyngeal tumors

PURPOSE

Oropharynx squamous cell carcinoma (OPSCC) is a subtype of head and neck squamous cell carcinoma (HNSCC) arising from the base of the tongue, lingual tonsils, tonsils, oropharynx or pharynx. The majority of HPV-positive OPSCCs has a good prognosis, but a fraction of them has a poor prognosis, similar to HPV-negative OPSCCs. An in-depth understanding of the molecular mechanisms underlying OPSCC is mandatory for the identification of novel prognostic biomarkers and/or novel therapeutic targets.

METHODS

14 HPV-positive and 15 HPV-negative OPSCCs with 5-year follow-up information were subjected to gene expression profiling and, subsequently, compared to three extensive published OPSCC cohorts to define robust biomarkers for HPV-negative lesions. Validation of Aldo-keto-reductases 1C3 (AKR1C3) by qRT-PCR was carried out on an independent cohort (n = 111) of OPSCC cases. In addition, OPSCC cell lines Fadu and Cal-27 were treated with Cisplatin and/or specific AKR1C3 inhibitors to assess their (combined) therapeutic effects.

RESULTS

Gene set enrichment analysis (GSEA) on the four datasets revealed that the genes down-regulated in HPV-negative samples were mainly involved in immune system, whereas those up-regulated mainly in glutathione derivative biosynthetic and xenobiotic metabolic processes. A panel of 30 robust HPV-associated transcripts was identified, with AKR1C3 as top-overexpressed transcript in HPV-negative samples. AKR1C3 expression in 111 independent OPSCC cases positively correlated with a worse survival, both in the entire cohort and in HPV-positive samples. Pretreatment with a selective AKR1C3 inhibitor potentiated the effect of Cisplatin in OPSCC cells exhibiting higher basal AKR1C3 expression levels.

CONCLUSIONS

We identified AKR1C3 as a potential prognostic biomarker in OPSCC and as a potential drug target whose inhibition can potentiate the effect of Cisplatin.

[Tumor biology of oropharyngeal carcinoma]

BACKGROUND

Etiologically, oropharyngeal squamous cell carcinoma (OPSCC) can be divided into OPSCC caused by noxious agents and human papillomavirus (HPV)-driven carcinoma. These types differ with regard to clinical features and prognosis-differences which are rooted in the underlying molecular biology of the tumor.

OBJECTIVE

The aim of this work is to provide an overview of the molecular biological characteristics of the genetics, epigenetics, and immunology of OPSCC.

MATERIALS AND METHODS

A literature review was performed on a selection of genetic, epigenetic, and immunological factors characterizing OPSCC.

RESULTS

The understanding of genetic aberrations and their consequences for cancerogenesis and tumor biology is increasing. Epigenetic phenomena are complementing functional relationships. However, epigenetic mechanisms of gene regulation are complex and much research is still required in this field. Immunological aspects of cancer molecular biology have moved into the focus in light of recent advances in the field of immunotherapy.

CONCLUSION

The tumor biology of OPSCC is primarily defined by its HPV status. Additionally, HPV-independent genetic, epigenetic, and immunological signatures are being defined. From these advances, rationales for new treatment concepts may evolve.

Safety and efficacy of single cycle induction treatment with cisplatin/docetaxel/ durvalumab/tremelimumab in locally advanced HNSCC: first results of CheckRad-CD8

Background

To determine safety and efficacy of single cycle induction treatment with cisplatin/docetaxel and durvalumab/tremelimumab in stage III-IVB head and neck cancer.

Methods

Patients received a single cycle of cisplatin 30 mg/m² on days 1–3 and docetaxel 75 mg/m² on day 1 combined with durvalumab 1500 mg fix dose on day 5 and tremelimumab 75 mg fix dose on day 5. Patients with pathologic complete response (pCR) in the rebiopsy after induction treatment or at least 20% increase of intratumoral CD8+ cell density in the rebiopsy compared with baseline entered radioimmunotherapy with concomitant durvalumab/tremelimumab. The objective of this interim analysis was to analyze safety and efficacy of the chemoimmunotherapy-induction treatment before radioimmunotherapy.

Results

A total of 57 patients were enrolled, 56 were treated. Median pretreatment intratumoral CD8+ cell density was 342 cells/mm². After induction treatment, 27 patients (48%) had a pCR in the rebiopsy and further 25 patients (45%) had a relevant increase of intratumoral CD8+ cells (median increase by a factor of 3.0). Adverse event (AE) grade 3–4 appeared in 38 patients (68%) and mainly consisted of leukopenia (43%) and infections (29%). Six patients (11%) developed grade 3–4 immune-related AE. Univariate analysis computed p16 positivity, programmed death ligand 1 immune cell area and intratumoral CD8+ cell density as predictors of pCR. On multivariable analysis, intratumoral CD8+ cell density predicted pCR independently (OR 1.0012 per cell/mm², 95% CI 1.0001 to 1.0022, p=0.016). In peripheral blood CD8+ cells, the coexpression of programmed death protein 1 significantly increased especially in patients with pCR.

Conclusions

Single cycle induction treatment with cisplatin/docetaxel and durvalumab/tremelimumab is feasible and achieves a high biopsy-proven pCR rate.

HNSCC: Tumour Antigens and Their Targeting by Immunotherapy

Head and neck squamous cell carcinomas (HNSCC) are a heterogeneous group of malignant tumours typically caused by alcohol and tobacco consumption, although an increasing number of HNSCC arise due to persistent infection with high-risk human papilloma virus (HPV). The treatment of HNSCC remains challenging, and the first-line setting is focused on surgery and chemoradiotherapy. A substantial proportion of HNSCC patients die from their disease, especially those with recurrent and metastatic disease. Among factors linked with good outcome, immune cell infiltration appears to have a major role. HPV-driven HNSCC are often T-cell rich, reflecting the presence of HPV antigens that are immunogenic. Tumour-associated antigens that are shared between patients or that are unique to an individual person may also induce varying degrees of immune response; studying these is important for the understanding of the interaction between the host immune system and the cancer. The resulting knowledge is critical for the design of better immunotherapies. Key questions are: Which antigens lead to an adaptive immune response in the tumour? Which of these are exploitable for immunotherapy? Here, we review the current thinking regarding tumour antigens in HNSCC and what has been learned from early phase clinical trials.

Immunological Network in Head and Neck Squamous Cell Carcinoma-A Prognostic Tool Beyond HPV Status

Head and neck squamous cell carcinoma (HNSCC) is a highly heterogeneous disease that affects more than 800,000 patients worldwide each year. The variability of HNSCC is associated with differences in the carcinogenesis processes that are caused by two major etiological agents, namely, alcohol/tobacco, and human papillomavirus (HPV). Compared to non-virally induced carcinomas, the oropharyngeal tumors associated with HPV infection show markedly better clinical outcomes and are characterized by an immunologically “hot” landscape with high levels of tumor-infiltrating lymphocytes. However, the standard of care remains the same for both HPV-positive and HPV-negative HNSCC. Surprisingly, treatment de-escalation trials have not shown any clinical benefit in patients with HPV-positive tumors to date, most likely due to insufficient patient stratification. The in-depth analysis of the immune response, which places an emphasis on tumor-infiltrating immune cells, is a widely accepted prognostic tool that might significantly improve both the stratification of HNSCC patients in de-escalation trials and the development of novel immunotherapeutic approaches.

Exceptional Response to PD-1 Blockade as First-Line Therapy in Head and Neck Squamous Cell Carcinoma

The effect of PD-1 blockade as a first-line therapy in nonmetastatic head and neck squamous cell carcinoma (HNSCC) remains unknown. We report a case of an exceptional response to PD-1 blockade as a first-line therapy in a patient with HNSCC and lung cancer. A 59-year-old man presented with cheek swelling and chest pain. He was diagnosed with maxillary sinus carcinoma (squamous cell carcinoma) and lung cancer (non-small-cell lung cancer, not otherwise specified). The maxillary sinus carcinoma was completely resolved after 8 cycles of pembrolizumab. Immune checkpoint blockade warrants further evaluation in previously untreated patients with HNSCC.

Identifying predictors of HPV-related head and neck squamous cell carcinoma progression and survival through patient-derived models

Therapeutic innovation for human papilloma virus-related (HPV+) head and neck squamous cell carcinomas (HNSCCs) is impaired by inadequate preclinical models and the absence of accurate biomarkers. Our study establishes the first well-characterized panel of patient-derived xenografts (PDXs) and organoids from HPV+ HNSCCs while determining fidelity of the models to the distinguishing genetic features of this cancer type. Despite low engraftment rates, whole exome sequencing showed that PDXs retain multiple distinguishing features of HPV+ HNSCC lost in existing cell lines, including PIK3CA mutations, TRAF3 deletion and the absence of EGFR amplifications. Engrafted HPV+ tumors frequently contained NOTCH1 mutations, thus providing new models for a negatively prognostic alteration in this disease. Genotype-phenotype associations in the models were then tested for prediction of tumor progression and survival in published clinical cohorts. Observation of high tumor mutational burdens (TMBs) in the faster-growing models facilitated identification of a novel association between TMB and local progression in both HPV+ and HPV- patients that was prognostic in HPV- cases. In addition, reduced E7 and p16^INK4A levels found in a PDX from an outlier case with lethal outcome led to detection of similar profiles among recurrent HPV+ HNSCCs. Transcriptional data from the Cancer Genome Atlas was used to demonstrate that the lower E2F target gene expression predicted by reduced E7 levels has potential as a biomarker of disease recurrence risk. Our findings bridge a critical gap in preclinical models for HPV+ HNSCCs and simultaneously reveal novel potential applications of quantifying mutational burden and viral oncogene functions for biomarker development.

Fewer tumour-specific PD-1+CD8+ TILs in high-risk "Infiltrating" HPV- HNSCC

BACKGROUND

The prognosis of HPV^- HNSCC was worse than that of HPV⁺ HNSCC. Analysis of tumours and tumour-infiltrating lymphocytes (TILs) may provide insight into the progression of HPV^- HNSCC.

METHODS

The tumour and TIL phenotypic characteristics of 134 HNSCC specimens (HPV^- tumours were classified into "Infiltrating" and "Pushing" subtypes based on their different tumour nest configuration and prognosis) were retrospectively analysed. HNSCC data from the Cancer Genome Atlas (n = 263) were analysed for CD8α, HPV and overall survival (OS). A murine HNSCC model was used to verify the antitumour role of PD-1⁺CD8⁺ TILs.

RESULTS

The "Infiltrating" HPV^- subtype showed shorter OS than the "Pushing" subtype. Moreover, there is a tendency from "Pushing" to "Infiltrating" subtype from the primary to the recurrent lesion. Different from total CD8⁺ TILs, tumour-specific PD-1⁺CD8⁺ TILs were fewer in invasive margin (IM) of "Infiltrating" HPV^- tumours. PD-1⁺CD8⁺ TILs recognised autologous HNSCC cells and showed stronger inhibition of tumour growth in a murine HNSCC model resistant to PD-1 blockade.

CONCLUSIONS

Coevolution of HPV^- HNSCC and TILs is characterised by an "Infiltrating" phenotype and less tumour-specific PD-1⁺CD8⁺ TILs, which may provide a framework for further translational studies and patient stratification.