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Summary Background Middle ear cholesteatoma is a cyst like structure composed of keratinizing squamous epithelium that contains keratin debris and subepithelial connective tissue. Bone resorption may lead to destruction of ossicular chain and temporal bone. The higher activity of N-acetyl-β-glucosaminidase (HEX) was noted in cholesteatoma tissue, compared to the controls. It is supposed, that HEX takes part in bone resorption in middle ear cholesteatoma. Using of HEX inhibitors in cultured fibroblasts and evaluation HEX mRNA expression may contribute to showing new ways of understanding cholesteatoma pathogenesis. The aim of the study was to elaborate cholesteatoma fibroblast cell culture (CF) technique and evaluate in vitro inhibition potential of pyrimethamine. Material and methods Cholesteatoma and normal retroauricular skin sample obtained during surgical treatment were used in the study. CF served as a study group and fibroblast derived from skin specimens – as controls. Pyrimethamine was used at the concentrations of 1.5, 3, 10 and 20 μg/ml. The reverse transcriptase-polymerase chain reaction (RT-PCR) was carried out for the determination of HEX gene expression. Results RT-PCR established the elevated expression of HEXA and HEXB mRNA in cholesteatoma. HEXA mRNA in CF was six times higher than in the controls. HEX mRNA expression found to be regulated by pyrimethamine. Inhibition of HEXA and HEXB mRNA expression was achieved when the highest concentration of PYR was used. Low concentrations of pyrimethamine upregulated HEX gene in CF. Conclusions Pyrimethamine, depending on its concentration, contributes to regulating the HEX gene expression in CF and controls. Pyrimethamine may be regarded as a new future research direction on factors, that may limit development of cholesteatoma.

Middle ear cholesteatoma is a cyst like structure composed of keratinizing squamous epithelium that contains keratin debris and subepithelial connective tissue. Bone resorption may lead to destruction of ossicular chain and temporal bone. The higher activity of N-acetyl-beta3-glucosaminidase (HEX) was noted in cholesteatoma tissue, compared to the controls. It is supposed, that HEX takes part in bone resorption in middle ear cholesteatoma. Using of HEX inhibitors in cultured fibroblasts and evaluation HEX mRNA expression may contribute to showing new ways of understanding cholesteatoma pathogenesis.was to elaborate cholesteatoma fibroblast cell culture (CF) technique and evaluate in vitro inhibition potential of pyrimethamine.Cholesteatoma and normal retroauricular skin sample obtained during surgical treatment were used in the study. CF served as a study group and fibroblast derived from skin specimens--as controls. Pyrimethamine was used at the concentrations of 1.5, 3, 10 and 20 microg/ml. The reverse transcriptase-polymerase chain reaction (RT-PCR) was carried out for the determination of HEX gene expression.RT-PCR established the elevated expression of HEXA and HEXB mRNA in cholesteatoma. HEXA mRNA in CF was six times higher than in the controls. HEX mRNA expression found to be regulated by pyrimethamine. Inhibition of HEXA and HEXB mRNA expression was achieved when the highest concentration of PYR was used. Low concentrations of pyrimethamine upregulated HEX gene in CF.Pyrimethamine, depending on its concentration, contributes to regulating the HEX gene expression in CF and controls. Pyrimethamine may be regarded as a new future research direction on factors, that may limit development of cholesteatoma.

Vocal fold polyp is usually a result of the injury of the vocal cords. It often appears after vocal overuse or misuse causing trauma in vocal fold mid-membranous and wound formation. THE AIM OF THE STUDY was to assess the activity of hexosaminidase in vocal fold polyps in the comparison to the control tissue.Vocal polyps (n=8) were collected from 8 patients during direct laryngoscopy. Specimens of normal vocal folds were obtained from 8 cadavers (n=8) served as controls. Specimens were immediately frozen in -80 degrees C. To assess hexosaminidase activity, release of p-nitrophenol from p-nitrophenol derivatives was used.We observed statistical differences between the activity of investigated enzyme in all vocal folds specimens compared with that in normal tissue homogenates. However the activity of HEX achieved a low level. Mean release of HEX from the activated cells in vocal fold specimens was 1.073 nkat/g wet tissue compared with 0.766 nkat/g wet tissue in normal cadaveric vocal fold homogenates.Low activity of HEX in vocal fold polyps suggests that inflammation may not be a primary factor in the development of the disease and other mechanism should likely be considered in the pathogenesis of vocal fold polyps.

Objectives Larynx squamous cell carcinoma is one of the most common forms of cancer in the area of the neck. The aim of our study was to investigate the activities of N-acetyl-β- d -hexosaminidase (HEX) in larynx cancer compared with the specimens from the healthy space of the tumor that served as controls. Design and methods Larynx cancer (n = 15) and normal healthy tissue around the tumor (n = 15) were collected from the patients during total laryngectomy. Specimens were immediately frozen in − 80 °C. To assess hexosaminidase activity, release of p-nitrophenol from p-nitrophenol derivatives was used. Results We observed a significantly higher activity of the investigated enzyme in all laryngeal cancer specimens compared with that in healthy tissue homogenates. The differences were statistically significant. Conclusions It could be assumed that HEX may release particular sugars from the ends of oligosaccharide chains of glycocalyx proteins, changing adhesive forces binding together cells, and the communication between cells and elements of extracellular matrix.