Jonathan M. Bock

Pepsin promotes proliferation of laryngeal and pharyngeal epithelial cells.

Laryngopharyngeal reflux (LPR) is thought to be a significant risk factor for laryngeal squamous cell carcinoma (SCC), but causality has never been proven. It is accepted that chronic reflux into the esophagus can induce metaplastic changes in esophageal mucosa with subsequent increased risk of esophageal adenocarcinoma, but no similar associations have been established for LPR and laryngopharyngeal SCC. The objective of this study was to test the hypothesis that reflux of pepsin into the laryngopharynx can promote carcinogenesis.

Celecoxib Toxicity Is Cell Cycle Phase Specific

Celecoxib inhibits proliferation and induces apoptosis in human tumors, but the molecular mechanisms for these processes are poorly understood. In this study, we evaluated the ability of celecoxib to induce toxicity in head and neck squamous cell carcinomas (HNSCC) and explored the relationships between celecoxib-induced cell cycle inhibition and toxicity in HNSCC. Celecoxib inhibited the proliferation of UM-SCC-1 and UM-SCC-17B cells both in vitro and in vivo, accompanied by G(1) phase cell cycle arrest and apoptosis. Celecoxib induced p21(waf1/cip1) at the transcriptional level independent of wild-type p53 function, leading to decreased expression of cyclin D1 and hypophosphorylation of Rb, with subsequent marked downstream decreases in nuclear E2F-1 protein expression and E2F transactivating activity by luciferase reporter assay. Cell cycle phase-specific cytometric sorting showed that celecoxib induced clonogenic toxicity preferentially to cells within the S phase greater than G(1) and G(2) phases. Levels of p21(waf1/cip1) and cyclin D1 protein were reduced in the S phase compared with the G(1) and G(2) phases, suggesting a possible protective role for p21(waf1/cip1) expression in celecoxib toxicity. In conclusion, we show that celecoxib has marked antiproliferative activity against head and neck cancer cells through transcriptional induction of p21(waf1/cip1) and G(1) phase accumulation leading to S phase-specific clonogenic toxicity. We additionally show that a profound inhibition of nuclear E2F function provides a possible mechanism for this S phase-specific toxicity.

Botulinum toxin injection for the treatment of upper esophageal sphincter dysfunction.

Objectives: We sought to review the dysphagia-related outcomes and quality of life in a series of patients with upper esophageal sphincter (UES) dysfunction treated with cricopharyngeal (CP) botulinum toxin (BTX) injection, and to identify patient characteristics or CP muscle histologic features that predict efficacy of BTX injection. Methods: A retrospective chart review was performed on patients with UES dysfunction who underwent CP BTX injection. Dysphagia-related quality-of-life questionnaires based on the Eating Assessment Tool (EAT-10) were mailed to patients. Results: Forty-nine patients (30 female, 19 male; average age, 59 ± 16 years) with UES dysfunction have been treated at our institution with CP BTX injection since 2000. Seventeen of these patients also underwent CP myotomy. Injections of BTX were occasionally repeated after the treatment effect subsided, and the BTX dose varied widely (average, 39 ± 19 units). Improvement in symptoms was noted by 65% of patients. The overall complication rate was minimal, although many patients complained of transient worsening of dysphagia after CP BTX injection. Biopsy specimens of the CP muscle were evaluated in the subset of patients with CP BTX injection who proceeded to myotomy, with results of neuropathic, myopathic, and mixed histologic subtypes. The EAT-10 scores demonstrated a general trend toward improved swallowing outcomes after CP BTX injection. Conclusions: This study reviewed findings from the largest published series of BTX treatment of UES dysfunction and evaluated the efficacy, patient satisfaction, and complications of this procedure. Dysphagia-related quality-of-life outcomes appear to be improved after CP BTX injection.

Modulation of Cellular Invasion by VEGF-C Expression in Squamous Cell Carcinoma of the Head and Neck

OBJECTIVE To determine how vascular endothelial growth factor C (VEGF-C) affects tumor cell invasion and motility in squamous cell carcinoma of the head and neck (SCCHN). DESIGN A molecular biology study. The VEGF-C coding sequence was cloned into an expression vector and stably transfected into the SCCHN cell line SCC116 to create the SCC116-VEGFC line. RNA interference (RNAi) was used to block VEGF-C expression. An adenoviral system for expressing VEGF-C RNAi was developed and tested. SETTING An academic hospital laboratory. MAIN OUTCOME MEASURES Relative VEGF-C RNA levels were determined by real-time quantitative reverse transcriptase-polymerase chain reaction, and protein expression was evaluated by Western blot. Cellular invasion was evaluated by 24-hour semipermeable membrane transit assay. RESULTS SCC116-VEGFC cells had markedly increased expression of VEGF-C protein and RNA compared with normal SCC116 controls. SCC116-VEGFC cells produced marked increases in cellular invasion and motility compared with SCC116 cells. Blockade of VEGF-C expression by transfection of a VEGF-C RNAi expression plasmid into both SCC116 and SCC116-VEGFC cells induced a 38% decrease in SCCHN invasion and motility as tested by a semipermeable membrane invasion assay. We developed an adenoviral expression system for VEGF-C RNAi, which also induced a dose-dependent decrease in cellular invasion in the highly invasive DM12 cell line. CONCLUSIONS These studies demonstrate that intracellular VEGF-C levels modulate in vitro SCCHN motility and invasion. Further work is needed to clarify the specific receptors and signaling pathways that are involved in SCCHN motility. Molecular therapies that inhibit the VEGF-C pathway may have clinical potential in the treatment of lymphatic metastasis in SCCHN.

Analysis of pepsin in tracheoesophageal puncture sites.

Objectives: Tracheoesophageal puncture (TEP) and prosthesis insertion is a well-established method of voice rehabilitation after laryngectomy. Maintenance of the prosthesis and tract can be challenging, and reflux to the TEP site has been proposed as a cause. The sites of TEP were evaluated for the presence of pepsin in tissue biopsy specimens and tract secretions to explore this association. Methods: Patients with TEP were interviewed for a history of symptoms related to reflux, medication use history, TEP voice quality, and incidence of TEP complications. Tissue biopsy specimens and tract secretions were obtained from TEP sites and analyzed for the presence of pepsin via sodium dodecyl sulfate–polyacrylamide gel electrophoresis Western blot analysis. Results: Twelve of 17 patients (47%) had some history of preoperative or postoperative symptoms of gastroesophageal reflux disease or laryngopharyngeal reflux. Pepsin was present within the TEP site in a total of 10 of 17 patients (58%; 7 of 17 tissue biopsy specimens and 6 of 7 secretion samples). There were no statistically significant associations between the presence of pepsin and sex, reflux history, use of acid suppressive medicine, or time since laryngectomy. Conclusions: Reflux with subsequent pepsin deposition into the TEP tract occurs in a majority of laryngectomy patients. Further studies on the effect of reflux on the health and function of the TEP tract are warranted.

Relative non-steroidal anti-inflammatory drug (NSAID) antiproliferative activity is mediated through p21-induced G1 arrest and E2F inhibition.

This study was performed to compare the relative antineoplastic activity of 10 different non‐steroidal anti‐inflammatory drugs (NSAIDs) in clinical use, and to investigate the underlying mechanisms of this activity in a squamous cell carcinoma of the head and neck model (SCCHN). A standard 5‐day MTT assay was used to calculate IC50 values in UM‐SCC‐1 cells for 10 NSAIDs, including celecoxib, rofecoxib, sulindac sulfide, sulindac sulfone, indomethacin, ketoprofen, flurbiprofen, naproxen, piroxicam, and aspirin. Celecoxib, a COX‐2 specific inhibitor, was by far the most potent NSAID, with an IC50 of 39.9 ± 1.1 µM, followed by sulindac sulfide (116.5 ± 2.34 µM). Celecoxib and sulindac sulfide also induced more activation of caspase‐3 than any other NSAID. Cell cycle analysis showed that celecoxib and sulindac sulfide both induced a 3‐fold increase in G1 phase distribution, and this correlated with strong induction of p21waf1/cip1, inhibition of cyclin D1, and hypophosphorylation of Rb. Celecoxib and sulindac sulfide treatment induced strong downstream inhibition of E2F transactivating activity as determined by a luciferase reporter assay. These data demonstrate the wide range of activity of various NSAID agents, and reveal a mechanism of action through cell cycle inhibition and induction of apoptosis.

Migration of Cymetra After Vocal Fold Injection for Laryngeal Paralysis

Injection laryngoplasty is a common operative technique used in the management of unilateral vocal fold paralysis. Cymetra is a micronized particulate injectable form of acellular human dermis that is commonly used for vocal cord medialization procedures. We report migration of an intracordal bolus of Cymetra into the medial wall of the pyriform sinus. Histopathology from endoscopic resection of the migrated Cymetra demonstrated a localized foreign body reaction with characteristic giant cells. Specific anatomic considerations through cadaveric laryngeal dissection are presented to demonstrate the likely pathway of intralaryngeal bolus migration.

Laryngopharyngeal Reflux: Paradigms for Evaluation, Diagnosis, and Treatment

Objective: This study aimed to describe current patterns for diagnosis and treatment of laryngopharyngeal reflux (LPR) and analyze differences between laryngologists and non-laryngologists. Methods: American Academy of Otolaryngology–Head and Neck Surgery and American Broncho-Esophagological Association members were invited to complete an online survey regarding evaluation, diagnosis, and treatment of LPR. Subgroup analysis was performed to identify differences between respondents who completed laryngology fellowships (LF) and those who did not (NL). Results: Of 159 respondents, 40 were LF. Video documentation of laryngopharyngeal exams was almost universal among LF (97% vs 38%, P < .0001). Use of rigid (100%, P = .002) and flexible distal-chip technologies (94%, P = .004) was more common among LF. Diagnostic criteria were similar between the groups, with symptoms of heartburn, globus, and throat clearing thought most suggestive of LPR. Adjunctive tests most commonly used were barium esophagram and dual-probe pH testing with impedance. Laryngology fellowship-trained respondents used dual pH probes with impedance more often (P = .004). They were more likely to prescribe twice daily proton pump inhibitors with concurrent H2-blocker medication initially (P = .004) and to treat for longer than 4 weeks (P = .0003). Conclusion: Otolaryngologists are in agreement on symptoms and physical features of LPR; however, significant differences exist between laryngologists and non-laryngologists on the use of adjunctive testing and treatment strategies.

A new noninvasive method for determination of laryngeal sensory function.

We report a new surface technique for studying sensory conduction in the superior laryngeal nerve (SLN).

Coblation-assisted lingual tonsillectomy for dysphagia secondary to tongue base hypertrophy.

Objectives: Lingual tonsillar hypertrophy is an underappreciated cause of dysphagia and is believed to impede swallowing function by inhibition of laryngeal elevation and epiglottic inversion due to mechanical interference by bulky tongue base tissue. We present a case of severe dysphagia secondary to idiopathic tongue base hypertrophy that was treated with coblation lingual tonsillectomy and tongue base reduction. Methods: We report a case and discuss the relevant literature regarding tongue base hypertrophy and surgical interventions to treat the enlarged base of the tongue. Results: Symptoms of dysphagia and globus sensation and signs of decreased epiglottic inversion and laryngeal penetration improved markedly after surgical reduction of hypertrophied lingual tonsillar tissue using coblation. Preoperative and postoperative clinical imaging and radiographs are presented to show the reduction of tongue base size, correlated with the patients improved clinical function. Conclusions: Coblation-assisted lingual tonsillectomy and tongue base reduction can successfully treat dysphagia secondary to tongue base hypertrophy.