Faculty Bibliography

The human homologue of the Drosophila segment polarity gene PTCH1, a tumor suppressor gene within the Sonic Hedgehog pathway has been implicated as the mutation responsible for nevoid basal cell carcinoma syndrome (NBCCS) as well as many other sporadic neoplasms. The calcifying epithelial odontogenic tumor (CEOT) is a rare and aggressive tumor of the jaws. The objective of this study was to investigate the role of the Sonic hedgehog pathway in the pathogenesis of the CEOT. We evaluated the protein distribution of PTCH and the transcription factors Gli1 and Gli2 within seven cases using immunohistochemistry. We also sought to confirm the findings by sequencing the PTCH1 gene from DNA extracted from the paraffin-embedded tissue of these cases. Seven cases of paraffin-embedded CEOT specimens were analyzed with immunohistochemistry. Immunoreactivity for Sonic hedgehog pathway proteins was evaluated using antibodies to the receptor PTCH as well as to the transcription factors Gli1 and Gli2. A keratocystic odontogenic tumor (KOT) from a 12year-old with NBCCS served as our positive control. Normal salivary gland tissue served as our negative control. PTCH gene sequencing was completed using PCR. Immunoreactivity to PTCH was seen in 6/7 cases, to Gli1 in 6/7 cases and to Gli2 in 6/7 cases. All three proteins were positive in the syndromic KOT and all proteins were negative in normal salivary tissue. Gene sequencing revealed five single-nucleotide polymorphisms (SNPs) of which two resulted in missense mutations. A missense mutation was also detected in the KOT. This study is the first to implicate the Sonic hedgehog pathway in the pathogenesis of the CEOT through sequencing. Similar to other odontogenic neoplasms gene mutations in PTCH1 are present in the CEOT

Endothelin-1 (ET-1) produced by various cancers is known to be responsible for inducing pain. While ET-1 binding to ETAR on peripheral nerves clearly mediates nociception, effects from binding to ETBR are less clear. The present study assessed the effects of ETBR activation and the role of endogenous opioid analgesia in carcinoma pain using an orthotopic cancer pain mouse model. mRNA expression analysis showed that ET-1 was nearly doubled while ETBR was significantly down-regulated in a human oral SCC cell line compared to normal oral keratinocytes (NOK). Squamous cell carcinoma (SCC) cell culture treated with an ETBR agonist (10(-4)M, 10(-5)M, and 10(-6) M BQ-3020) significantly increased the production of beta-endorphin without any effects on leu-enkephalin or dynorphin. Cancer inoculated in the hind paw of athymic mice with SCC induced significant pain, as indicated by reduction of paw withdrawal thresholds in response to mechanical stimulation, compared to sham-injected and NOK-injected groups. Intratumor administration of 3mg/kg BQ-3020 attenuated cancer pain by approximately 50% up to 3h post-injection compared to PBS-vehicle and contralateral injection, while intratumor ETBR antagonist BQ-788 treatment (100 and 300microg/kg and 3mg/kg) had no effects. Local naloxone methiodide (500microg/kg) or selective mu-opioid receptor antagonist (CTOP, 500microg/kg) injection reversed ETBR agonist-induced antinociception in cancer animals. We propose that these results demonstrate that peripheral ETBR agonism attenuates carcinoma pain by modulating beta-endorphins released from the SCC to act on peripheral opioid receptors found in the cancer microenvironment

Mediators involved in the generation of pain in patients with cancer are poorly understood. Using a combined molecular, pharmacologic, behavioral, and genetic approach, we have identified a novel mechanism of cancer-dependent allodynia induced by protease-activated receptor 2 (PAR2). Here we show that human head and neck carcinoma cells have increased levels of proteolytic activity compared to normal human cell controls. Supernatant from human carcinoma cells, but not controls, caused marked and prolonged mechanical allodynia in mice, when administered into the hindpaw. This nociceptive effect was abolished by serine protease inhibition, diminished by mast cell depletion and absent in PAR2-deficient mice. In addition, non-contact co-culture of trigeminal ganglion neurons with human head and neck carcinoma cells increased the proportion of neurons that exhibited PAR2-immunoreactivity. Our results point to a direct role for serine proteases and their receptor in the pathogenesis of cancer pain. This previously unrecognized cancer pain pathway has important therapeutic implications wherein serine protease inhibitors and PAR2 antagonists may be useful for the treatment of cancer pain

Endobronchial ultrasonography (EBUS) has emerged as a new diagnostic tool that allows the bronchoscopist to see beyond the airway, including pulmonary and mediastinal lesion. The real time EBUS-guided transbronchial needle aspiration (TBNA) has advanced the diagnostic yield in primary lung pathology and mediastinal lymph node staging of lung carcinoma. Sixty-four patients (36 males, 28 females, ages ranging from 16 to 86 years) with peribronchial lung lesions and mediastinal and/or hilar lymph node lesions underwent EBUS-TBNA. All patients had intraoperative cytological assessment by smears on aspiration samples or touch preparation on needle core biopsies.The cytological final diagnoses were categorized as negative, suspicious/positive, and non-diagnostic. Forty-nine samples were obtained from lymph node lesions and 15 samples were obtained from lung lesions. In cytology specimens, 32 patients had suspicious/positive diagnoses and 32 patients had negative diagnosis. In follow-up histology specimens, 35 patients had malignant diagnoses, including 18 adenocarcinomas, 8 small cell carcinomas, 6 squamous cell carcinomas, 1 metastatic hepatocellular carcinoma, 1 metastatic melanoma, and 1 lymphoma. Twenty-nine patients had negative diagnoses. Sensitivity and specificity were 88.9% and 96.4%, respectively. Positive and negative predictive values were 97.0% and 87.1%, respectively. Diagnostic accuracy was 92.2%. EBUS-TBNA is an efficient and effective technique for diagnosis of intrapulmonary and mediastinal/hilar lymph nodes. It becomes significantly invaluable on clinical management for staging in those patients with lung cancer of other metastatic malignancies. This technique enables us to obtain tissue samples for quick diagnoses beyond central airway with minimal complications. Diagn. Cytopathol. 2010. (c) 2009 Wiley-Liss, Inc

BACKGROUND: Radiation therapy (RT) to the head and neck often results in damage to the vocal folds (VF) and surrounding structures. Characterization and treatment of these sequelae is limited, likely due to the lack of experimental models. METHODS: Larynges from rats exposed to 2 fractionation schedules (40 Gy total) were analyzed histologically. In vitro, reactive oxygen species (ROS) synthesis, and transcription of select genes associated with ROS, inflammation, and fibrosis were examined in VF fibroblasts after single-dose radiation. RESULTS: Although radiation-induced histologic alterations are made to VF architecture, 1 fractionation schedule was accompanied by significant morbidity and mortality. In vitro, radiation increased ROS synthesis and inflammatory and profibrotic gene expression. CONCLUSION: Our data suggest that hyperfractionated RT is more tolerable. Utilizing this model, RT-induced histologic aberrations are made to the VF mucosa. In addition, a relationship between radiation, ROS, and inflammatory and fibrotic gene expression was observed in vitro

OBJECTIVES: Actinomycosis is a rare disease with a typically indolent course in the head and neck. During the modern era, only 12 cases within the ear and temporal bone and 75 intracranial cases have been reported. We present a case of actinomycosis of the petrous apex that led to meningitis and encephalitis. METHODS: The patient was a 12-year-old girl who presented with mental status changes. After 48 hours of treatment with empiric antibiotics for meningitis without improvement, imaging revealed an enhancing mass in the right petrous apex, destruction of the cochlea, meningeal enhancement, and left temporoparietal encephalitis. RESULTS: The initial therapy included broad-spectrum antibiotic, antifungal, and antiviral agents, as well as myringotomy and tympanostomy tube placement. When the patient's clinical status worsened, she underwent subtotal petrosectomy with drainage of the petrous apex. The final pathologic findings were consistent with actinomycosis. CONCLUSIONS: Actinomycosis is a rare infection in the temporal bone and central nervous system that can have a high mortality risk if not treated appropriately. Often, these bacteria do not grow well in culture, and diagnosis must be made on the basis of histopathologic features. Good clinical outcomes can be obtained with surgical debridement followed by long-term antibiotic treatment

Auditory thresholds with standardized clinical procedures are obtained over a much narrower frequency range by bone conduction than by air conduction. As a result, diagnostic information for both sensorineural and conductive-mechanism function is incomplete for high frequencies. A new magnetostrictive bone-conduction transducer that has the potential for improved output in the high-frequency range was evaluated in the laboratory and in a variety of subjects with normal hearing (N=11) or sensorineural hearing loss (N=9). Laboratory results indicated that harmonic distortion and acoustic radiation were both sufficiently low to allow accurate threshold measurements. Auditory thresholds obtained with this magnetostrictive bone-conduction transducer can be measured accurately under conventional clinical conditions for frequencies up to 16 kHz and levels up to 85 dB HL. These measures can be used to accurately characterize sensorineural hearing sensitivity for high frequencies and, when combined with standard air-conduction measures for high frequencies, to accurately characterize conductive-mechanism function for frequencies higher than possible with current diagnostic bone-conduction technology.

BACKGROUND: Half of the patients with head and neck squamous cell carcinoma (HNSCC) can be expected to fail therapy, indicating that more aggressive treatment is warranted for this group. We have developed a novel risk model that can become a basis for developing new treatment paradigms. Here we report on the performance of our model in a new multicenter cohort. DESIGN: Eligible patients from 3 institutions (Montefiore Medical Center, University of Manitoba, and New York University Medical Center) were identified and pathology slides from their resection specimens were reviewed by Margaret Brandwein-Gensler; risk category was assigned as previously published. Kaplan-Meier analysis was performed for disease progression and survival. Cox proportional hazards regression was performed, adjusted for potential confounders. A teaching module was also developed; attending pathologists were asked to score coded slides after a lecture and multiheaded microscope teaching session. Agreement was assessed by calculating Cohen unweighted kappa coefficients. RESULT: The validation cohort consisted of 305 patients, from the above institutions, with 311 primary HNSCC of the oral cavity, oropharynx, and larynx. The median follow-up period for all patients was 27 months. Risk category predicts time to disease progression (P=0.0005), locoregional recurrence (P=0.013), and overall survival (P=0.0000) by Kaplan-Meier analysis. High-risk status is significantly associated with decreased time to disease progression, adjusted for clinical confounders (P=0.015, hazard ratio 2.32, 95% confidence interval 1.18-4.58) compared with collapsed intermediate and low-risk groups. We also demonstrate substantial interrater agreement (kappa=0.64), and very good rater agreement when compared with the standard (kappa=0.87). CONCLUSIONS: We demonstrate significant predictive performance of the risk model in a new cohort of patients with primary HNSCC, adjusted for confounders. Our training experience also supports the feasibility of adapting the risk model in clinical practice

HYPOTHESIS: A new intraoral bone-conduction device has advantages over existing bone-conduction devices for reducing the auditory deficits associated with single-sided deafness (SSD). BACKGROUND: Existing bone-conduction devices effectively mitigate auditory deficits from single-sided deafness but have suboptimal microphone locations, limited frequency range, and/or require invasive surgery. A new device has been designed to improve microphone placement (in the ear canal of the deaf ear), provide a wider frequency range, and eliminate surgery by delivering bone-conduction signals to the teeth via a removable oral appliance. METHODS: Forces applied by the oral appliance were compared with forces typically experienced by the teeth from normal functions such as mastication or from other appliances. Tooth surface changes were measured on extracted teeth, and transducer temperature was measured under typical use conditions. Dynamic operating range, including gain, bandwidth, and maximum output limits, were determined from uncomfortable loudness levels and vibrotactile thresholds, and speech recognition scores were measured using normal-hearing subjects. Auditory performance in noise (Hearing in Noise Test) was measured in a limited sample of SSD subjects. Overall comfort, ease of insertion, and removal and visibility of the oral appliance in comparison with traditional hearing aids were measured using a rating scale. RESULTS: The oral appliance produces forces that are far below those experienced by the teeth from normal functions or conventional dental appliances. The bone-conduction signal level can be adjusted to prevent tactile perception yet provide sufficient gain and output at frequencies from 250 to 12,000 Hz. The device does not damage tooth surfaces nor produce heat, can be inserted and removed easily, and is as comfortable to wear as traditional hearing aids. The new microphone location has advantages for reducing the auditory deficits caused by SSD, including the potential to provide spatial cues introduced by reflections from the pinna, compared with microphone locations for existing devices. CONCLUSION: A new approach for SSD has been proposed that optimizes microphone location and delivers sound by bone conduction through a removable oral appliance. Measures in the laboratory using normal-hearing subjects indicate that the device provides useful gain and output for SSD patients, is comfortable, does not seem to have detrimental effects on oral function or oral health, and has several advantages over existing devices. Specifically, microphone placement is optimized for reducing the auditory deficit caused by SSD, frequency bandwidth is much greater, and the system does not require surgical placement. Auditory performance in a small sample of SSD subjects indicated a substantial advantage compared with not wearing the device. Future studies will involve performance measures on SSD patients wearing the device for longer periods.