MYO7A and USH2A gene sequence variants in Italian patients with usher syndrome Molecular Vision, 2014
Identification of autoantibodies against inner ear antigens in a cohort of children with idiopathic sensorineural hearing loss Elettra Berti, Gaia Vannucci, Claudio Lunardi, Benedetta Bianchi, Caterina Bason, et al. Autoimmunity, 2013 Immune-mediated pathogenesis has been suggested for idiopathic sensorineural hearing loss. Recent studies have investigated the relationship between idiopathic sensorineural hearing loss and autoantibodies against inner ear antigens. We conducted a prospective, observational study in a series of pediatric patients affected by idiopathic sensorineural hearing loss. Autoantibodies against inner ear (anti-Cogan peptide, anti-connexin 26, anti-DEP1/CD148 and anti-reovirus), previously described in the serum of patients with Cogan’s syndrome, were detected in our population. The characteristics of children whose results were positive were also evaluated to verify if clinical data, disease progression and response to treatment could confirm an immune-mediated pathogenesis. Eleven patients were enrolled and 9 of them were positive for inner ear antibodies. Non-organ specific autoantibodies were present in 5 children out of 9. An immune-mediated condition was diagnosed in 2 cases and minor immune manifestations were found in 2 additional patients. In 5 cases hearing loss remained stable without therapy, while 4 children developed progression. Two subjects were treated with corticosteroids and methotrexate, achieving hearing improvement. Another subject showed stabilization on methotrexate. Inner ear autoantibodies can be positive in children with autoimmune sensorineural hearing loss, and in conjunction with clinical data may assist the clinician in identifying a subset amenable for immune modulation therapy. Large prospective studies are needed to investigate usefulness, diagnostic and prognostic role of these autoantibodies.
Profound hypokalemia and hypochloremic metabolic alkalosis during thiazide therapy in a child with Pendred syndrome I. Pela, M. Bigozzi, B. Bianchi Clinical Nephrology, 2008 Pendred syndrome is a recessive autosomal disorder characterized by thyroid goiter and sensorineural hearing loss. The Pendred syndrome gene (SLC26A4) encodes a new anion exchanger named pendrin which mediates iodide transport by thyrocytes and regulates ion and fluid transport by the endolymphatic sac epithelium. Pendrin defects result in inner ear malformations, with enlargement of the endolymphatic sac and duct in association with a large vestibular aqueduct. Furthermore, patients may develop endolymphatic hydrops requiring diuretic therapy, mainly in the form of thiazides. Pendrin could also account for apical Cl(-)/ HCO3(-) exchange at level of intercalated cells of the cortical collecting duct in the kidneys, however, humans with Pendred syndrome have no symptoms attributable to renal pendrin abnormalities in basal conditions. We report the case of a child with Pendred syndrome and intercurrent endolymphatic hydrops, who developed profound hypokalemia and severe hypochloremic metabolic alkalosis (potassium 1.7, chloride 70, sodium 129, HCO3 43.8, base excess +17.8 mmol/l, pH 7.52) following thiazide therapy. In subjects with Pendred syndrome thiazide therapy seems to provoke more severe Cl(-) and extracellular volume depletion. A possible explanation could be the defective action of the disrupted pendrin, which exacerbates the effects of the inhibition of C1(-) reabsorption mediated by the thiazide-sensitive NaCl cotransporter (SLC12A3).
Prognostic significance of cyclooxygenase-2 pathway and angiogenesis in head and neck squamous cell carcinoma Oreste Gallo, Emanuela Masini, Benedetta Bianchi, Luca Bruschini, Milena Paglierani, et al. Human Pathology, 2002 Prostaglandins play a critical role in tumor development and growth by regulating numerous biologic processes, including tumor angiogenesis, with clear prognostic and therapeutic implications. The aim of this study was to investigate the prognostic relevance of cyclooxygenase-2 (COX-2) pathway activation in head and neck squamous cell carcinoma (HNSCC). COX-2 activity was analyzed in 52 consecutive patients by assessing protein expression and prostaglandin E(2) (PgE(2)) levels and was then correlated to vascular endothelial growth factor (VEGF) expression and tumor angiogenesis. We evaluated the prognostic impact of these parameters by Kaplan-Meier and Cox survival analysis. COX-2 expression by tumor cells was closely correlated to VEGF expression and to tumor vascularization. According to Kaplan-Meier analysis, patients with COX-2 tumor overexpression and with higher PgE(2) tumor levels had significantly shorter overall survival estimates (P = 0.022 and P = 0.033, respectively). Analogously, patients with more-vascularized tumors had worse survival than those with less-vascularized cancers (P = 0.032). Cox multivariate analysis demonstrated that the most significant prognostic factors were presence of lymph node metastasis, tumor vascularization, COX-2 protein expression, and PgE(2) tumor levels. This study demonstrates a close correlation between COX-2 pathway, VEGF expression, and tumor angiogenesis in HNSCC. In addition, COX-2 overexpression and higher tumor vascularization appear to predict a shorter survival in patients with head and neck cancer.
