Stathmin as a surrogate marker of phosphatidylinositol-3-kinase pathway activity: Towards precision medicine in HPV-negative head & neck squamous cell carcinoma.

In order to assess Stathmin as an immunohistochemical (IHC) indicator of phosphatidylinositol 3-kinase (PI3K) pathway activity in HPV-negative head & neck squamous cell carcinoma (HNSCC), we compared Stathmin IHC to expression of other pathway components. We also evaluated the relationship between Stathmin IHC and the mutational status of four key pathway genes. Finally, we ascertained whether Stathmin IHC correlates with tumor grade or primary site. Correlation exists between high Stathmin expression and high pAKT1 expression, indicating a role for Stathmin IHC as a marker of pathway activity. Our analysis did not show correlation between Stathmin IHC and mutation of the four genes evaluated. We also observed an association between high Stathmin expression and oropharyngeal primary site. Our results suggest utility of Stathmin IHC as an indicator of PI3K pathway activity, and thereby demonstrate potential relevance of Stathmin IHC in the context of HNSCC.

Oncogenic PIK3CA mutation and dysregulation in human salivary duct carcinoma.

Salivary duct carcinoma (SDC) is an aggressive malignant tumor with a high mortality, which resembles high-grade breast ductal carcinoma in morphology. The parotid gland is the most common location. Its molecular genetic characteristics remain largely unknown. We have previously reported high incidence of PIK3CA somatic mutations in head and neck squamous cell carcinoma, particularly in pharyngeal cancers. Here we examined the PIK3CA gene expression status and hotspot mutations in six cases of SDC by immunohistochemistry and genomic DNA sequencing. Immunohistochemistry showed that PIK3CA expression was elevated in all six patients with SDC. By DNA sequencing, two hotspot mutations of the PIK3CA gene, E545K (exon 9) and H1047R (exon 20), were identified in two of the six cases. Our results support that oncogenic PIK3CA is upregulated and frequently mutated in human SDC, adding evidence that PIK3CA oncogenic pathway is critical in the tumorigenesis of SDC, and may be a plausible drug target for this rare disease.

Topical Application of Green Tea Polyphenol (-)-Epigallocatechin-3-gallate (EGCG) for Prevention of Recurrent Oral Neoplastic Lesions.

OBJECTIVE: A preliminary study was conducted to investigate feasibility of using an oral cancer chemopreventive agent (-)-epigallocatechin-3-gallate (EGCG), the most biologically active component in the green tea extract, in a form of 'swish-and-spit' mouthwash. Such application of EGCG is beneficial as it maximizes exposure of the oral mucosa to the agent but minimizes systemic side effect. STUDY DESIGN: The study was conducted on individuals suspected to have oral field cancerization who are at a high risk for developing recurrent oral precancerous and carcinomatous lesions. EGCG was used as a daily mouthwash for 7 days. EGCG's ability to modulate target molecules implicated in oral carcinogenesis was assessed by measuring the change in expression level of biomarkers. RESULTS: Immunohistochemical expression of phosphoactivated epidermal growth factor receptor (pEGFR), cyclooxygenase-2 (cox-2) and ki-67 were evaluated at baseline and at the endpoint (day 8). Although not statistically significant, overall decrease in expression levels of pEGFR (27.5%), cox-2 (15.9%) and ki-67 positive cells (51.8%) were observed following EGCG treatment. Moreover, a detectable level of EGCG was found in saliva but not in plasma after the one-week treatment regime, demonstrating local availability of EGCG in oral mucosa without significant systemic absorption. CONCLUSION: To best of our knowledge this is the first study to explore use of oral cancer chemopreventive agent in a form of mouthwash in patients with oral field cancerization. Although a definitive conclusion was not reached due to limited sample size, if proven effective, EGCG therapy may offer a non-invasive preventive modality for oral field cancerization.

Multiple tumor-suppressor genes on chromosome 3p contribute to head and neck squamous cell carcinoma tumorigenesis.

Head and neck squamous cell carcinoma (HNSCC) remains a significant cause of morbidity and mortality. There has been a great interest in finding specific genomic changes which contribute to HNSCC tumorigenesis, especially within the chromosome 3p area, where high frequency of LOH (loss of heterozygosity) has been reported. However, tumor-suppressor genes that may account for the frequent LOH remain to be identified. Recently, one systematic study of genomic sequencing was performed on breast and colorectal cancers and 189 candidate cancer genes (CAN-genes) were reported. Among those CAN-genes, 13 genes are located on chromosome 3p. To investigate whether any of the 13 CAN-genes on chromosome 3p is relevant to HNSCC tumorigenesis, we examined their mutational profiles in eight HNSCC cell lines and 12 tumor-normal pairs of human HNSCC in this study. Three of the 13 CAN-genes, ALS2CL, EPHA3, and CMYA1, each was found to harbor a missense mutation (1/20, 5% for each of the three genes). The mutations appeared hemizygous and SNP array analyses showed that these missense mutations are accompanied by LOH on the remaining allele. In summary, our data offer further support that ALS2CL, EPHA3, and CMYA1 are bona-fide tumor-suppressor genes and contribute to the tumorigenesis of HNSCC. Our data suggest that multiple tumor-suppressor genes are likely to be involved in accounting for the high LOH on chromosome 3p in HNSCC.

Novel mutant-enriched sequencing identified high frequency of PIK3CA mutations in pharyngeal cancer.

We previously reported 4 PIK3CA mutations in 38 head and neck cancer samples, 3 of which were identified in 6 pharyngeal cancer samples. To determine the mutation frequency of PIK3CA in pharyngeal cancer, we studied 24 additional cases of pharyngeal squamous cell carcinoma in this study. Using both direct genomic DNA sequencing and novel mutant-enriched sequencing methods developed specifically for the 3 hot-spot mutations (H1047R, E545K and E452K) of PIK3CA, we detected 5 mutations of PIK3CA in the 24 pharyngeal cancers (20.8%). Three of the 5 mutations had been missed by the conventional sequencing method and were subsequently detected by novel mutant-enriched sequencing methods. We showed that the mutant-enriched sequencing method for the H1047R hot-spot mutation can identify the mutation in a mixed population of mutant and wild-type DNA sequences at 1:360 ratios. These novel mutant-enriched sequencing methods allow the detection of the PIK3CA hot-spot mutations in clinical specimens which often contain limited tumor tissues (i.e., biopsy specimens). The data further support that oncogenic PIK3CA may play a critical role in pharyngeal carcinogenesis, and the mutant-enriched sequencing methods for PIK3CA are sensitive and reliable ways to detect PIK3CA mutations in clinical samples. Because PIK3CA and its pathway are potential targets for chemotherapy and radiation therapy, and frequent somatic mutation of PIK3CA has been identified in many human cancer types (e.g., breast cancer, colorectal cancer), the abilities to detect PIK3CA mutations with enhanced sensitivities have great potential impacts on target therapies for many cancer types.

PIK3CA mutations in head and neck squamous cell carcinoma.

PURPOSE: Recent studies have reported high frequencies of somatic mutations in the phosphoinositide-3-kinase catalytic alpha (PIK3CA) gene in several human solid tumors. Although gene amplifications of PIK3CA have been reported in head and neck squamous cell carcinoma (HNSCC), small mutation of the gene has not been evaluated in HNSCC previously. In this study, we examined the mutation frequency of PIK3CA in HNSCC. EXPERIMENTAL DESIGN: More than 75% of the somatic mutations of PIK3CA are clustered in the helical (exon 9) and kinase domains (exon 20). To investigate the possible role of PIK3CA in HNSCC tumorigenesis, exons 1, 4, 5, 6, 7, 9, and 20 of the gene were analyzed by direct genomic DNA sequencing in 38 HNSCC specimens. RESULTS: We identified four missense mutations in the seven exons of PIK3CA from 38 HNSCC specimens (11%). Three of the four mutations (i.e., H1047R, E542K, and E545K) have been previously reported as hotspot mutations. The remaining novel mutation, Y343C, is identified at exon 4 nucleotide 1028 A --> G. Three of the four mutations were shown to be somatic, whereas the fourth mutation (H1047R) was identified in a cell line. Interestingly, three of the four mutations identified were in pharyngeal cancer samples. CONCLUSIONS: These data provide evidence that oncogenic properties of PIK3CA contribute to the carcinogenesis of human head and neck cancers, especially in pharyngeal cancer. A specific kinase inhibitor to PIK3CA may potentially be an effective therapeutic reagent against HNSCC or pharyngeal cancer in particular.

"Balanced" orbital decompression for severe Graves' orbitopathy: technique with treatment algorithm.

BACKGROUND: Graves' orbitopathy can produce proptosis, compressive optic neuropathy, and extraocular motility abnormalities; symptoms result from an increase in orbital volume due to expansion of intraorbital fat, with or without extraocular muscle involvement. STUDY DESIGN: We conducted a chart review of patients who underwent orbital decompression to treat Graves' orbitopathy. Twenty-two orbits (13 patients) underwent orbital bone decompression, of which 17 orbits (9 patients) underwent the combined medial and lateral "balanced" decompression. RESULTS: All patients had significant improvement with an average decrease in proptosis of 5.9 mm in the balanced decompression group. Restoration of normal optic nerve function was achieved in all patients with compressive optic neuropathy. Diplopia was noted in 4 patients (30.7%) preoperatively. Two patients had new postoperative diplopia (15.35%). CONCLUSION: In our experience, "balanced" decompression results in a reduction of proptosis and improved optic nerve function and has a low incidence of complications.

Combined modality treatment of Ewing's sarcoma of the maxilla.

BACKGROUND: Primary bone sarcomas arising in osseous structures of the head and neck are rare. These tumors are often incompletely resected and treated with radiotherapy for local control. METHODS: We report a case of a 9-year-old girl with a maxillary Ewing's sarcoma. This patient was successfully treated with neoadjuvant chemotherapy followed by surgical resection and prosthetic reconstruction of the primary site. The surgical approach that was used consisted of a subtotal maxillectomy by means of a facial degloving approach, sparing the orbital contents and the inferior orbital rim and orbital floor. RESULTS: This approach produced excellent cosmetic, functional, and oncologic outcome. The patient remains without evidence of disease recurrence more than 4 years after surgery. CONCLUSIONS: This case illustrates a novel surgical approach to the resection of a maxillary Ewing's sarcoma and highlights the need for a multidisciplinary team approach to the management of head and neck sarcomas in children.

Laryngeal adductor reflex and pharyngeal squeeze as predictors of laryngeal penetration and aspiration.

OBJECTIVES: The contribution of laryngopharyngeal (LP) sensory deficits to the outcome of swallowing and the relationship between sensory and motor deficits in the laryngopharynx is unclear. The study purpose is to determine if patients with LP sensory and motor deficits are at increased risk for laryngeal penetration and aspiration during swallowing, and to determine the relationship between pharyngeal motor weakness and LP sensory deficits. MATERIALS AND METHODS: Endoscopic evaluation of swallowing with sensory testing was performed on 122 dysphagic patients who were prospectively divided into two groups. The control group was 76 patients with normal sensitivity, determined by an intact laryngeal adductor reflex (LAR) on air pulse stimulation of the mucosa innervated by the superior laryngeal nerve. The study group was 46 patients with severe sensory deficits, determined by an absent LAR. Each group was given puree followed by thin liquid, noting presence or absence of laryngeal penetration and aspiration. Pharyngeal muscle strength was assessed by noting presence or absence of pharyngeal contraction during voluntary adduction of the vocal folds (pharyngeal squeeze). RESULTS: In control subjects, with purees, 6 of 76 (7.90%) penetrated and 3 of 76 (3.94%) aspirated; with thins, 26 of 76 (34.2%) penetrated and 13 of 76 (17.1%) aspirated. In the absent LAR group, with purees, 39 of 46 (84.8%) penetrated and 32 and 46 (69.6%) aspirated; with thins, 46 of 46 (100%) penetrated and 43 of 46 (93.5%) aspirated. For both consistencies, the differences in prevalence of penetration and aspiration between groups was significant (P <.0001, chi2). In control subjects, pharyngeal squeeze was impaired in 17 of 76 (22.4%), with penetration of puree in 6 of 17 (35.3%) and aspiration in 3 of 17 (17.6%). In the absent LAR group, squeeze was impaired in 41 of 46 (89.1%), with penetration of puree in 39 of 41 (95.1%) and aspiration in 32 of 41 (78.0%). The difference in the prevalence of pharyngeal weakness between groups was significant (P <.0001). The difference in the prevalence of penetration and aspiration was higher in the absent LAR/impaired contraction cohort than in the normal sensation/impaired contraction cohort (P <.0001). CONCLUSION: Absence of the LAR and impaired pharyngeal squeeze puts patients with dysphagia at high risk for laryngeal penetration and aspiration compared with patients with an intact LAR and intact pharyngeal squeeze. There is a strong association between motor and sensory deficits in the laryngopharynx.