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Assessment of membranous EGFR expression in PECAPJ49 parental and CTXR#4 treated with and without cetuximab

Schematic representing the generation of acquired cetuximab resistant HNSCC models

Evaluation of RTK and BRD4 expression from clinical HNSCC datasets

Determination and validation of BRD4 expression in acquired cetuximab-resistant HNSCC models.

Lung cancer model of acquired cetuximab resistance display increased RTK expression and sensitivity to BET inhibition

Evaluation of RTK and Ki67 expression in PDX6282 treated with cetuximab and JQ1

Evaluation of basal BRD4 expression in HNSCC cell lines and PDXs.

Cetuximab, the FDA-approved anti-EGFR antibody for head and neck squamous cell carcinoma (HNSCC), has displayed limited efficacy due to the emergence of intrinsic and acquired resistance. We and others have demonstrated that cetuximab resistance in HNSCC is driven by alternative receptor tyrosine kinases (RTK), including HER3, MET, and AXL. In an effort to overcome cetuximab resistance and circumvent toxicities associated with the administration of multiple RTK inhibitors, we sought to identify a common molecular target that regulates expression of multiple RTK. Bromodomain-containing protein-4 (BRD4) has been shown to regulate the transcription of various RTK in the context of resistance to PI3K and HER2 inhibition in breast cancer models. We hypothesized that, in HNSCC, targeting BRD4 could overcome cetuximab resistance by depleting alternative RTK expression. We generated independent models of cetuximab resistance in HNSCC cell lines and interrogated their RTK and BRD4 expression profiles. Cetuximab-resistant clones displayed increased expression and activation of several RTK, such as MET and AXL, as well as an increased percentage of BRD4-expressing cells. Both genetic and pharmacologic inhibition of BRD4 abrogated cell viability in models of acquired and intrinsic cetuximab resistance and was associated with a robust decrease in alternative RTK expression by cetuximab. Combined treatment with cetuximab and bromodomain inhibitor JQ1 significantly delayed acquired resistance and RTK upregulation in patient-derived xenograft models of HNSCC. These findings indicate that the combination of cetuximab and bromodomain inhibition may be a promising therapeutic strategy for patients with HNSCC.Significance: Inhibition of bromodomain protein BRD4 represents a potential therapeutic strategy to circumvent the toxicities and financial burden of targeting the multiple receptor tyrosine kinases that drive cetuximab resistance in HNSCC and NSCLC.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/15/4331/F1.large.jpg. Cancer Res; 78(15); 4331–43. ©2018 AACR.

Response and RTK expression of acquired cetuximab resistant HNSCC models

Objective In small (≤2 cm) oral tongue squamous cell carcinoma (OTSCC), we sought to clarify the contribution of pathologic features including perineural invasion (PNI), lymphovascular invasion (LVI), and worst pattern of invasion-5 (WPOI-5) to clinical outcomes relative to tumor depth of invasion (DOI) of > or ≤ 4 mm. Methods Cases of ≤2 cm OTSCC treated surgically between 2000 and 2017 at an academic cancer center were reviewed, with retrospective pathologic slide review of DOI, LVI, PNI, and WPOI-5. Primary outcome measures included occult nodal positivity, 2-year locoregional recurrence (LRR), disease-specific survival (DSS), and overall survival (OS). Results One hundred tumors were included in analyses; 50 had DOI ≤ 4 mm, while 50 had DOI > 4 mm. When DOI was ≤4 mm, the presence of PNI, LVI, or WPOI-5 was not associated with higher rates of occult cervical metastasis, LRR, or OS. When DOI was >4 mm, there was no difference in rates of occult cervical metastasis or LRR with each feature. On multivariate analysis, only the presence of two or more adverse features was associated with higher LRR (OR 5.7, P = .01) and worse DSS (HR 6.5, P = .02). Conclusion The rate of occult cervical metastases in small (≤2 cm) OTSCC when DOI is ≤4 mm is very low even when PNI, LVI, or WPOI-5 is present, and 2-year LRR is no different. When DOI is >4 mm, the strongest predictor of recurrence and survival on multivariate analysis is the presence of two or more features in the tumor. Level of evidence 4 Laryngoscope, 130:1715-1720, 2020.

Objective: To develop and validate an automated smartphone app that determines bone-conduction pure-tone thresholds. Methods: A novel app, called EarBone, was developed as an automated test to determine best-cochlea pure-tone bone-conduction thresholds using a smartphone driving a professional-grade bone oscillator. Adult, English-speaking patients who were undergoing audiometric assessment by audiologists at an academic health system as part of their prescribed care were invited to use the EarBone app. Best-ear bone-conduction thresholds determined by the app and the gold standard audiologist were compared. Results: Forty subjects with varied hearing thresholds were tested. Sixty-one percent of app-determined thresholds were within 5 dB of audiologist-determined thresholds, and 79% were within 10 dB. Nearly all subjects required assistance with placing the bone oscillator on their mastoid. Conclusion: Best-cochlea bone-conduction thresholds determined by the EarBone automated smartphone audiometry app approximate those determined by an audiologist. This serves as a proof of concept for automated smartphone-based bone-conduction threshold testing. Further improvements, such as the addition of contralateral ear masking, are needed to make the app clinically useful.

Cetuximab, the FDA-approved anti-EGFR antibody for head and neck squamous cell carcinoma (HNSCC), has displayed limited efficacy due to the emergence of intrinsic and acquired resistance. We and others have demonstrated that cetuximab resistance in HNSCC is driven by alternative receptor tyrosine kinases (RTK), including HER3, MET, and AXL. In an effort to overcome cetuximab resistance and circumvent toxicities associated with the administration of multiple RTK inhibitors, we sought to identify a common molecular target that regulates expression of multiple RTK. Bromodomain-containing protein-4 (BRD4) has been shown to regulate the transcription of various RTK in the context of resistance to PI3K and HER2 inhibition in breast cancer models. We hypothesized that, in HNSCC, targeting BRD4 could overcome cetuximab resistance by depleting alternative RTK expression. We generated independent models of cetuximab resistance in HNSCC cell lines and interrogated their RTK and BRD4 expression profiles. Cetuximab-resistant clones displayed increased expression and activation of several RTK, such as MET and AXL, as well as an increased percentage of BRD4-expressing cells. Both genetic and pharmacologic inhibition of BRD4 abrogated cell viability in models of acquired and intrinsic cetuximab resistance and was associated with a robust decrease in alternative RTK expression by cetuximab. Combined treatment with cetuximab and bromodomain inhibitor JQ1 significantly delayed acquired resistance and RTK upregulation in patient-derived xenograft models of HNSCC. These findings indicate that the combination of cetuximab and bromodomain inhibition may be a promising therapeutic strategy for patients with HNSCC. Significance: Inhibition of bromodomain protein BRD4 represents a potential therapeutic strategy to circumvent the toxicities and financial burden of targeting the multiple receptor tyrosine kinases that drive cetuximab resistance in HNSCC and NSCLC. Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/15/4331/F1.large.jpg. Cancer Res; 78(15); 4331–43. ©2018 AACR.

The genomic landscape of head and neck squamous cell carcinoma (HNSCC) has been recently elucidated. Key epigenetic and genetic characteristics of this cancer have been reported and substantiated in multiple data sets, including those distinctive to the growing subset of human papilloma virus (HPV)–associated tumors. This increased understanding of the molecular underpinnings of HNSCC has not resulted in new approaches to treatment. Three Food and Drug Administration–approved molecular targeting agents are currently available to treat recurrent/metastatic disease, but these have exhibited efficacy only in subsets of HNSCC patients, and thus surgery, chemotherapy, and/or radiation remain as standard approaches. The lack of predictive biomarkers to any therapy represents an obstacle to achieving the promise of precision medicine. This review aims to familiarize the reader with current insights into the HNSCC genomic landscape, discuss the currently approved and promising molecular targeting agents under exploration in laboratories and clinics, and consider precision medicine approaches to HNSCC.

BACKGROUND AND OBJECTIVES: To determine the rate of ocular hypertension (OHT) after dexamethasone intravitreal implant in routine clinical practice and identify patient characteristics associated with a risk for glaucoma surgery. PATIENTS AND METHODS: The charts of 260 eyes from 221 patients with diabetic macular edema, retinal vein occlusion, uveitis, and macular edema secondary to various causes treated with one or more dexamethasone implants were reviewed. Intraocular pressure (IOP), medications, and glaucoma interventions were collected before and after implantation. RESULTS: The mean baseline IOP was 14.3 mm Hg ± 3.6 mm Hg, and after receiving dexamethasone implant(s), 26.2% and 7.7% of patients had IOP greater than 25 mm Hg and 35 mm Hg, respectively. There was evidence ( P < .001) of an association between preexisting glaucoma or glaucoma suspect status (103 eyes) and need for glaucoma surgery, and 4.62% (12 eyes) required glaucoma surgery. CONCLUSIONS: Secondary OHT induced by the dexamethasone implant can usually be controlled by medications, but the incidence of OHT requiring glaucoma surgery was high (4.62%) in our study relative to rates previously reported in the literature. All patients, especially those with preexisting glaucoma, should be advised of the possible need for glaucoma surgery prior to undergoing treatment with the dexamethasone implant. [ Ophthalmic Surg Lasers Imaging Retina . 2018;49:680–685.]

Transparency of the human cornea is necessary for vision. Fuchs Endothelial Corneal Dystrophy (FECD) is a bilateral, heritable degeneration of the corneal endothelium, and a leading indication for corneal transplantation in developed countries. While the early onset, and rarer, form of FECD has been linked to COL8A2 mutations, the more common, late onset form of FECD has genetic mutations linked to only a minority of cases. Epigenetic modifications that occur in FECD are unknown. Here, we report on and compare the DNA methylation landscape of normal human corneal endothelial (CE) tissue and CE from FECD patients using the Illumina Infinium HumanMethylation450 (HM450) DNA methylation array. We show that DNA methylation profiles are distinct between control and FECD samples. Differentially methylated probes (10,961) were identified in the FECD samples compared with the control samples, with the majority of probes being hypermethylated in the FECD samples. Genes containing differentially methylated sites were disproportionately annotated to ontological categories involving cytoskeletal organization, ion transport, hematopoetic cell differentiation, and cellular metabolism. Our results suggest that altered DNA methylation patterns may contribute to loss of corneal transparency in FECD through a global accumulation of sporadic DNA methylation changes in genes critical to basic CE biological processes.