Faculty Bibliography

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.

Despite the success of immune checkpoint blockade therapy, few strategies sufficiently overcome immunosuppression within the tumor microenvironment (TME). Targeting regulatory T cells (T_regs) is challenging, because perturbing intratumoral T_reg function must be specific enough to avoid systemic inflammatory side effects. Thus, no T_reg-targeted agents have proven both safe and efficacious in patients with cancer. Neuropilin-1 (NRP1) is recognized for its role in supporting intratumoral T_reg function while being dispensable for peripheral homeostasis. Nonetheless, little is known about the biology of human NRP1⁺ T_regs and the signals that regulate NRP1 expression. Here, we report that NRP1 is preferentially expressed on intratumoral T_regs across six distinct cancer types compared to healthy donor peripheral blood [peripheral blood lymphocyte (PBL)] and site-matched, noncancer tissue. Furthermore, NRP1⁺ T_reg prevalence is associated with reduced progression-free survival in head and neck cancer. Human NRP1⁺ T_regs have broad activation programs and elevated suppressive function. Unlike mouse T_regs, we demonstrate that NRP1 identifies a transient activation state of human T_regs driven by continuous T cell receptor (TCR) signaling through the mitogen-activated protein kinase pathway and interleukin-2 exposure. The prevalence of NRP1⁺ T_regs in patient PBL correlates with the intratumoral abundance of NRP1⁺ T_regs and may indicate higher disease burden. These findings support further clinical evaluation of NRP1 as a suitable therapeutic target to enhance antitumor immunity by inhibiting T_reg function in the TME.

OBJECTIVES:To determine which surgical factors are associated with quality-of-life (QOL) outcomes in oral cavity cancer survivors after free flap reconstruction of the oral cavity. PATIENTS AND METHODS:A cross-sectional study was conducted from a multidisciplinary head and neck cancer (HNC) survivorship clinic. Oral cavity cancer survivors with at least 6-months of postoperative follow-up from ablation and free flap reconstruction were included. Primary outcome measures were validated patient-reported outcome measures (PROMs) including the Eating Assessment Tool-10 (EAT-10) measure of swallowing-specific QOL, University of Washington Quality of Life (UW-QOL) physical and social-emotional subscale scores and feeding tube dependence. RESULTS:Extent of tongue resection was associated with EAT-10 and the UW-QOL Physical subscale scores. Patients with oral tongue defects reported worse scores than with composite defects in the EAT-10 and UW-QOL physical domain (p = 0.0004, 0.0025, respectively). This association no longer applies when controlling for differences in extent of tongue resection. Patients with anterior composite resections reported worse EAT-10 scores than lateral resections (p = 0.024). This association no longer applies when controlling for extent of tongue resection (p = 0.46). Gastric tube dependence demonstrates similar trends to PROMs. CONCLUSION:Extent of tongue resection was strongly associated with poor QOL outcomes after free tissue reconstruction of the oral cavity and mediates the associations between other defect characteristics and QOL. These findings demonstrate the need for emphasis on expected oral tongue defects when counseling patients and highlight the need to address QOL in a multidisciplinary fashion post-operatively.

PURPOSE:Human papillomavirus (HPV) infection drives the development of some head and neck squamous cell carcinomas (HNSCC). This disease is rapidly increasing in incidence worldwide. Although these tumors are sensitive to treatment, approximately 10% of patients fail therapy. However, the mechanisms that underlie treatment failure remain unclear. EXPERIMENTAL DESIGN:, (ii) oxidative phosphorylation (OXPHOS) inhibition using IACS-010759 on NRF2-dependent cells, and (iii) combination of cisplatin and OXPHOS inhibition. RESULTS:The OXPHOS pathway is enriched in recurrent HPV-associated HNSCC and may contribute to treatment failure. NRF2-enriched HNSCC samples from The Cancer Genome Atlas (TCGA) with enrichment in OXPHOS, fatty-acid metabolism, Myc, Mtor, reactive oxygen species (ROS), and glycolytic signaling networks exhibited worse survival. HPV-positive HNSCC cells demonstrated sensitivity to the OXPHOS inhibitor, in a NRF2-dependent manner. Further, using murine xenograft models, we identified NRF2 as a driver of tumor growth. Mechanistically, NRF2 drives ROS and mitochondrial respiration, and NRF2 is a critical regulator of redox homeostasis that can be crippled by disruption of OXPHOS. NRF2 also mediated cisplatin sensitivity in endogenously overexpressing primary HPV-related HNSCC cells. CONCLUSIONS:These results unveil a paradigm-shifting translational target harnessing NRF2-mediated metabolic reprogramming in HPV-related HNSCC.

The epidermal growth factor receptor (EGFR) inhibitor cetuximab is the only FDA-approved oncogene-targeting therapy for head and neck squamous cell carcinoma (HNSCC). Despite variable treatment response, no biomarkers exist to stratify patients for cetuximab therapy in HNSCC. Here, we applied unbiased hierarchical clustering to reverse-phase protein array molecular profiles from patient-derived xenograft (PDX) tumors and revealed 2 PDX clusters defined by protein networks associated with EGFR inhibitor resistance. In vivo validation revealed unbiased clustering to classify PDX tumors according to cetuximab response with 88% accuracy. Next, a support vector machine classifier algorithm identified a minimalist biomarker signature consisting of 8 proteins - caveolin-1, Sox-2, AXL, STING, Brd4, claudin-7, connexin-43, and fibronectin - with expression that strongly predicted cetuximab response in PDXs using either protein or mRNA. A combination of caveolin-1 and Sox-2 protein levels was sufficient to maintain high predictive accuracy, which we validated in tumor samples from patients with HNSCC with known clinical response to cetuximab. These results support further investigation into the combined use of caveolin-1 and Sox-2 as predictive biomarkers for cetuximab response in the clinic.

BACKGROUND:Insufficient exposure may require termination of procedure in transoral robotic surgery (TORS). The aim of study was to develop a "Pharyngoscore" to quantify the risk of difficult oropharyngeal exposure (DOE) before TORS. METHODS:Three-hundred six patients undergoing any surgical procedure at one Academic Hospital were prospectively enrolled. Oropharynx was exposed with Feyh-Kastenbauer retractor. Exposure was evaluated by direct and endoscopic visualization of the four oropharyngeal subsites. Preoperative clinical/anthropometric parameters were studied in good oropharyngeal exposure and DOE groups. Logistic regression was performed to explore association between clinical/anthropometric parameters and DOE. Statistically significant parameters at multivariate analysis were incorporated into a nomogram. RESULTS:Sixty-five (21.2%) subjects were characterized by DOE. Variables associated with DOE at univariate analysis were male (p = 0.031), modified Mallampati Class (MMC) ≥ III (p < 0.001), smaller interincisor gap (p < 0.001), and larger neck circumference (p = 0.006). MMC, interincisor gap, and neck circumference were significant at multivariate analysis and were presented with a nomogram for creating the Pharyngoscore. CONCLUSIONS:The Pharyngoscore is a promising tool for calculating DOE probability before TORS.

The neck dissection is an integral component of comprehensive oncologic care for patients with head and neck cancer. Modern robotic surgical platforms are being utilized within otolaryngology for a growing number of indications, including, robot-assisted neck dissections. The proposed benefits of robot-assisted include improved cosmesis and reductions in post-operative lymphedema. Early data suggests that oncologic control following robot-assisted neck dissection is comparable to the gold-standard, open technique. Here we present review of the surgical techniques involved in a robot-assisted neck dissection as well as a review of perioperative care.