Highlights • The majority of head and neck cancers display high effector immune cell infiltration. • Head and neck cancer cells utilize many defined mechanisms to escape immune elimination. • An ...immunosuppressive immune infiltrate contributes heavily to local immune suppression. • Modulation of immune escape mechanisms may enhance responses to standard and immune therapies.
Checkpoint inhibitors are relatively inefficacious in head and neck cancers, despite an abundance of genetic alterations and a T-cell-inflamed phenotype. One significant barrier to efficacy may be ...the recruitment of myeloid-derived suppressor cells (MDSC) into the tumor microenvironment. Here we demonstrate functional inhibition of MDSC with IPI-145, an inhibitor of PI3Kδ and PI3Kγ isoforms, which enhances responses to PD-L1 blockade. Combination therapy induced CD8
T lymphocyte-dependent primary tumor growth delay and prolonged survival only in T-cell-inflamed tumor models of head and neck cancers. However, higher doses of IPI-145 reversed the observed enhancement of anti-PD-L1 efficacy due to off-target suppression of the activity of tumor-infiltrating T lymphocytes. Together, our results offer a preclinical proof of concept for the low-dose use of isoform-specific PI3Kδ/γ inhibitors to suppress MDSC to enhance responses to immune checkpoint blockade.
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Local immunosuppression remains a critical problem that limits clinically meaningful response to checkpoint inhibition in patients with head and neck cancer. Here, we assessed the impact of MDSC ...elimination on responses to CTLA-4 checkpoint inhibition.
Murine syngeneic carcinoma immune infiltrates were characterized by flow cytometry. Granulocytic MDSCs (gMDSCs) were depleted and T-lymphocyte antigen-specific responses were measured. Tumor-bearing mice were treated with MDSC depletion and CTLA-4 checkpoint blockade. Immune signatures within the human HNSCC datasets from The Cancer Genome Atlas (TCGA) were analyzed and differentially expressed genes from sorted human peripheral MDSCs were examined.
gMDSCs accumulated with tumor progression and correlated with depletion of effector immune cells. Selective depletion of gMDSC restored tumor and draining lymph node antigen-specific T-lymphocyte responses lost with tumor progression. A subset of T-cell inflamed tumors responded to CTLA-4 mAb alone, but the addition of gMDSC depletion induced CD8 T-lymphocyte-dependent rejection of established tumors in all treated mice that resulted in immunologic memory. MDSCs differentially expressed chemokine receptors. Analysis of the head and neck cancer TCGA cohort revealed high CTLA-4 and MDSC-related chemokine and an MDSC-rich gene expression profile with a T-cell inflamed phenotype in > 60% of patients. CXCR2 and CSF1R expression was validated on sorted peripheral blood MDSCs from HNSCC patients.
MDSCs are a major contributor to local immunosuppression that limits responses to checkpoint inhibition in head and neck cancer. Limitation of MDSC recruitment or function represents a rational strategy to enhance responses to CTLA-4-based checkpoint inhibition in these patients.
To study the geographic utilization of videolaryngostroboscopy (VLS) with the hypothesis that office-based voice care is unevenly distributed across the United States.
This is a cross-sectional ...database analysis of Medicare beneficiaries. The Centers for Medicare and Medicaid Services Provider Utilization and Payment Data Physician and Other Supplier Public Use File from 2012 to 2017 was analyzed to evaluate VLS utilization. VLS distribution was assessed by calculating the density of VLS in each of the 306 hospital referral regions (HRRs) nationally. Associations between VLS density and population demographics and health system factors were assessed using Pearson correlation and multivariate regression analyses.
In total, 957,648 outpatient VLS were billed to Medicare part B between 2012 and 2017. The annual VLS density per HRR ranged from 0 to 38.2 per 1,000 enrollees. Pearson correlation revealed positive correlations between VLS density and number of Medicare enrollees (r = 0.2584, P < 0.001), income (r = 0.1913, P = 0.0008), education (r = 0.2089, P = 0.0002), and density of otolaryngologists (r = 0.1589, P = 0.0053) and medical specialists (r = 0.2326, P < 0.0001). A negative Pearson correlation was observed between VLS density and percent male (r = −0.1338, P = 0.0192) and Medicare mortality rate (r = −0.1628, P = 0.0043). On multivariate regression positive associations between VLS and number of Medicare enrollees (P = 0.002) and otolaryngologists (P = 0.049), and negative association with Medicare mortality rates (P = 0.032) remained significant.
The distribution of office-based voice care varies widely across the country, even when analysis by HRR should have homogenized access to specialty care. Greater availability of VLS is seen in HRRs with more Medicare enrollees, greater density of otolaryngologists, and lower mortality rates.
Objectives
Laryngotracheal stenosis (LTS) is a fibrotic condition of the upper airway. Recent evidence suggests dysregulated host immunity plays a role in LTS development and progression. The ...programmed death‐1 (PD‐1)/programmed death‐ligand 1 (PD‐L1) axis, targeted by paradigm‐shifting immunotherapies for cancer treatment, has also recently been implicated in the pathogenesis of fibrotic pulmonary disease. However, a role for the PD‐1/PD‐L1 axis in the proximal airway fibrosis seen in LTS patients has not been explored.
Study Design
Controlled ex vivo study.
Methods
Expression of PD‐1, PD‐L1, CD4, and CD8 were evaluated using immunohistochemical staining of cricotracheal resection specimens from postintubation iatrogenic laryngotracheal stenosis (iLTS), idiopathic subglottic stenosis (iSGS) patients, and normal controls derived from rapid autopsy (n = 8 per group). Fibroblasts derived from iLTS scar were also treated with transforming growth factor beta 1 (TGFβ1) and analyzed for PD‐L1 expression by quantitative real‐time polymerase chain reaction (n = 6).
Results
iLTS specimens exhibited increased expression of PD‐1, PD‐L1, and CD4 (all P < .0167) compared to controls, whereas iSGS specimens exhibited increased expression of PD‐1 and CD4 (P < .0167) compared to controls. PD‐1, PD‐L1, and CD4 showed periepithelial patterns of expression in both disease cohorts. TGFβ1 treatment of iLTS fibroblasts increased expression of PD‐L1 (the cognate ligand for PD‐1).
Conclusion
Expression of both PD‐1 and its ligand PD‐L1 are significantly greater in patients with iLTS compared to controls, and PD‐1 expression is also elevated in patients with iSGS. Given published evidence implicating the PD‐1/PD‐L1 axis in pulmonary fibrosis, this suggests a possible role for checkpoint inhibitors targeting the PD‐1/PD‐L1 axis for the treatment of LTS.
Level of Evidence
N/A Laryngoscope, 131:967–974, 2021
To describe laryngeal findings and voice quality in patients with suspected lung cancer, relative to voice quality and possible laryngeal pathology.
Prospective cohort study.
Tertiary care center.
...Patients with known or suspected lung cancer were approached before planned thoracic surgery, and they completed acoustic analysis, the Voice-Related Quality of Life (V-RQOL) questionnaire, and stroboscopy. The prevalence of dysphonia, V-RQOL and Cepstral Spectral Index of Dysphonia (CSID) scores, and laryngeal findings were examined and compared between patients ultimately found to have lung cancer and those without cancer.
Sixty-one patients (45 cancer, 16 noncancer) were analyzed. Patients with cancer were older than those without (mean ± SD, 72.3 ± 9.94 vs 62.6 ± 9.30 years;
= .001). Otherwise, the distribution of stroboscopy findings, acoustic measures, and self-reported voice handicap were similar between the cancer and noncancer cohorts. Prior to surgery, no patients had vocal cord paralysis or obvious neoplasm, though 4 (6.56%) had leukoplakia and 28 (45.9%) had vocal fold movement asymmetry on stroboscopy. Overall, 21 patients (35.0%) had average CSID scores >19, and 13 (21.7%) had CSID scores >24; however, only 4 self-described their voice as not working as it should, and only 2 had a V-RQOL score <85.
Patients with suspected lung cancer have moderate dysphonia on acoustic measures, though self-reported impact on quality of life is low. While leukoplakia was seen in 4 patients, obvious neoplasm and occult paralysis were not seen in this cohort. Together, these findings suggest that patients with suspected lung cancer should be assessed for subjective voice dysfunction, but routine laryngeal screening may otherwise be unnecessary.
Objectives
Recent translational scientific efforts in subglottic stenosis (SGS) support a disease model where epithelial alterations facilitate microbiome displacement, dysregulated immune ...activation, and localized fibrosis. Yet despite recent advances, the genetic basis of SGS remains poorly understood. We sought to identify candidate risk genes associated with an SGS phenotype, investigate their biological function, and identify the cell types enriched for their expression.
Methods
The Online Mendelian Inheritance in Man (OMIM) database was queried for single gene variants associated with an SGS phenotype. The functional intersections and molecular roles of the identified genes were explored using pathway enrichment analysis (PEA) computational methods. Cellular localization of the candidate risk genes was measured via transcriptional quantification in an established single cell RNA sequencing (scRNA‐seq) atlas of the proximal airway.
Results
Twenty genes associated with SGS phenotype were identified. PEA resulted in 24 significantly enriched terms including “cellular response to TGF‐β,” “epithelial‐to‐mesenchymal transition,” and “adherens junctions.” Mapping the 20 candidate risk genes to the scRNA‐seq atlas found 3 (15%) genes were enriched in epithelial cells, 3 (15%) in fibroblasts, and 3 (15%) in endothelial cells. 11 (55%) genes were expressed ubiquitously among tissue types. Interestingly, immune cells were not significantly enriched for candidate risk genes.
Conclusion
We identify and provide biologic context for 20 genes associated with fibrotic disease of the proximal airway and form the foundation for future detailed genetic study.
Level of evidence
N/A Laryngoscope, 133:3049–3056, 2023
Despite recent advances, the genetic basis of subglottic stenosis (SGS) remains poorly understood. We identify 20 candidate risk genes associated with an SGS phenotype, investigate their biological function, and determine the cell types enriched for their expression in a single‐cell RNA sequencing atlas. Our results offer new insights into the genetic architecture underlying fibrotic disease of the proximal airway.
To describe technical aspects and surgical outcomes of endoscopic resection and mucosal reconstitution with epidermal grafting (ie, the Maddern procedure) in the treatment of idiopathic subglottic ...stenosis.
Medical record abstraction.
Johns Hopkins Hospital.
Retrospective series of 9 adults with idiopathic subglottic stenosis who underwent the Maddern procedure by a single surgeon over a 5-year period. Prespecified outcomes included (1) perioperative outcomes (Clavien-Dindo grade 4/5 complications, need for staged tracheostomy, hospital length of stay), (2) postoperative outcomes (peak expiratory flow rate PEFR, need for subsequent airway surgery, tracheostomy at follow-up), and (3) patient-reported quality-of-life outcomes (Clinical COPD Questionnaire, Voice Handicap Index-10, Eating Assessment Tool-10, and 12-Item Short Form Version 2). Wilcoxon matched-pairs signed rank test and Kaplan-Meier analysis were performed.
There were no Clavien-Dindo grade 4/5 complications; 2 patients required unplanned staged tracheostomy; and the median length of stay was 3 days. Following endoscopic resection and stent removal, a median of 2 laser resurfacing procedures were required. Two patients developed recurrent stenosis requiring cricotracheal resection (CTR). There were significant improvements in PEFR, Clinical COPD Questionnaire, and Voice Handicap Index-10, without significant difference in Eating Assessment Tool-10. The 12-Item Short Form Version 2 approximated the population norm. Kaplan-Meier analysis demonstrated significant improvement in time to surgery after the final laser resurfacing.
The Maddern procedure has a low complication rate and offers durable physiologic improvement in PEFR, limiting need for additional procedures. Risks included need for CTR salvage, temporary tracheostomy, phlegm accumulation, and laryngospasm. It is a surgical option for patients with short dilation intervals who prefer to avoid the risks of CTR.
Objective
Characterize and quantify epithelium in multiple etiologies of laryngotracheal stenosis (LTS) to better understand its role in pathogenesis.
Study Design
Controlled in vitro cohort study.
...Methods
Endoscopic brush biopsy samples of both normal (non‐scar) and scar were obtained in four patients with idiopathic subglottic stenosis (iSGS) and four patients with iatrogenic LTS (iLTS). mRNA expression of basal, ciliary, and secretory cell markers were evaluated using quantitative PCR. Cricotracheal resection tissue samples (n = 5 per group) were also collected, analyzed using quantitative immunohistochemistry, and compared with rapid autopsy tracheal samples.
Results
Both iSGS and iLTS‐scar epithelium had reduced epithelial thickness compared with non‐scar control epithelium (P = .0009 and P = .0011, respectively). Basal cell gene and protein expression for cytokeratin 14 was increased in iSGS‐scar epithelium compared with iLTS or controls. Immunohistochemical expression of ciliary tubulin alpha 1, but not gene expression, was reduced in both iSGS and iLTS‐scar epithelium compared with controls (P = .0184 and P = .0125, respectively). Both iSGS and iLTS‐scar had reductions in Mucin 5AC gene expression (P = .0007 and P = .0035, respectively), an epithelial goblet cell marker, with reductions in secretory cells histologically (P < .0001).
Conclusions
Compared with non‐scar epithelium, the epithelium within iSGS and iLTS is morphologically abnormal. Although both iSGS and iLTS have reduced epithelial thickness, ciliary cells, and secretory cells, only iSGS had significant increases in pathological basal cell expression. These data suggest that the epithelium in iSGS and iLTS play a common role in the pathogenesis of fibrosis in these two etiologies of laryngotracheal stenosis.
Setting
Tertiary referral center (2017–2020).
Level of Evidence
NA Laryngoscope, 132:2194–2201, 2022
Myeloid-derived suppressor cells (MDSCs) have garnered much attention in recent years as a potential target for altering the immunosuppressive tumor microenvironment in a variety of solid tumor ...types. The ability to accurately assess the immunosuppressive capacity of MDSCs is fundamental to the development of therapeutic approaches aimed at disabling these immunosuppressive functions. In this article we provide evidence that the use of CD3/28 coated microbeads leads to artefactual T-lymphocyte suppression due to sequestration of beads by MDSCs isolated from the spleens of wild-type mice bearing subcutaneous syngeneic, carcinogen-induced oral cavity carcinomas. Mechanisms of this finding may include early MDSC death and acquisition of phagocytic capacity. These artefactual findings were avoided by eliminating the use of microbeads and instead using plate bound CD3/28 antibody as the T-lymphocyte stimulus. We propose model-specific validation of microbead-based MDSC assays, or use of an alternative stimulation approach such as plate bound CD3/28 antibodies.
•Sorted myeloid derived suppressor cells (MDSCs) rapidly gained phagocytic capacity before losing viability in culture•CD3/28 coated microbeads were sequestered away from target T-lymphocytes resulting in artefactual suppression•Utilizing plate bound CD3/28 antibodies allowed assessment of physiologic T-lymphocyte suppression by MDSCs
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