Objective: Salivary gland neoplasms pathogenesis has not been well established. DNA methylation o... more Objective: Salivary gland neoplasms pathogenesis has not been well established. DNA methylation occurs when methyl groups are added to cytosine nucleotides in specific areas of the gene by the enzyme DNA methyltransferase (DNMT). This chemical modification can alter gene expression without altering DNA sequence. While DNMT3a is mostly involved in de novo methylation, DNMT1 acts as a maintenance methyltransferase. We aimed to investigate the immunoexpression of DNMT3a and DNMT1 in minor salivary gland neoplasms, comparing it with normal tissue. Material: Forty-four formalin-fixed and paraffin-embedded samples of pleomorphic adenoma, adenoid cystic carcinoma, mucoepidermoid carcinoma and polymorphous low-grade adenocarcinoma were included in the study. The DNMT1 and DNMT3a proteins were identified by using a highly sensitive polymer-based system. Results: Positive nuclear and cytoplasmic labeling for DNMT1 was observed in all samples, including the controls. Positive nuclear labeling ...
Chronic renal disease is characterised by progressive and irreversible loss of renal function. A ... more Chronic renal disease is characterised by progressive and irreversible loss of renal function. A number of systemic and oral complications are associated with chronic renal disease. We report a rare case of jaw enlargement caused by the simultaneous presence of osteitis fibrosis and brown tumour secondary to hyperparathyroidism. Both conditions are related to increased levels of parathyroid hormone and dental surgeons should be aware of this important complication associated with chronic renal disease.
BACKGROUND: Although clonal origin is an essential step in the comprehension of neoplasias, there... more BACKGROUND: Although clonal origin is an essential step in the comprehension of neoplasias, there have been no studies to examine whether odontogenic tumours are derived from a single somatic progenitor cell. The purpose of this study was to investigate the clonal origin of odontogenic tumours. METHODS: Fresh samples of seven ameloblastomas, two odontogenic mixomas, two adenomatoid odontogenic tumour, one calcifying odontogenic cyst, one calcifying epithelial odontogenic tumour (CEOT) and six odontogenic keratocyst (OKC) of female patients were included in this study. After DNA extraction, the HUMARA gene polymorphism assay was performed. RESULTS: Most of the informative odontogenic lesions studied (12 out of 16) showed a monoclonal pattern. Among the polyclonal cases, two were OKC, one CEOT and one odontogenic mixoma. CONCLUSIONS: Our results suggest that most odontogenic tumours are monoclonal.
Objective: Salivary gland neoplasms pathogenesis has not been well established. DNA methylation o... more Objective: Salivary gland neoplasms pathogenesis has not been well established. DNA methylation occurs when methyl groups are added to cytosine nucleotides in specific areas of the gene by the enzyme DNA methyltransferase (DNMT). This chemical modification can alter gene expression without altering DNA sequence. While DNMT3a is mostly involved in de novo methylation, DNMT1 acts as a maintenance methyltransferase. We aimed to investigate the immunoexpression of DNMT3a and DNMT1 in minor salivary gland neoplasms, comparing it with normal tissue. Material: Forty-four formalin-fixed and paraffin-embedded samples of pleomorphic adenoma, adenoid cystic carcinoma, mucoepidermoid carcinoma and polymorphous low-grade adenocarcinoma were included in the study. The DNMT1 and DNMT3a proteins were identified by using a highly sensitive polymer-based system. Results: Positive nuclear and cytoplasmic labeling for DNMT1 was observed in all samples, including the controls. Positive nuclear labeling ...
Chronic renal disease is characterised by progressive and irreversible loss of renal function. A ... more Chronic renal disease is characterised by progressive and irreversible loss of renal function. A number of systemic and oral complications are associated with chronic renal disease. We report a rare case of jaw enlargement caused by the simultaneous presence of osteitis fibrosis and brown tumour secondary to hyperparathyroidism. Both conditions are related to increased levels of parathyroid hormone and dental surgeons should be aware of this important complication associated with chronic renal disease.
BACKGROUND: Although clonal origin is an essential step in the comprehension of neoplasias, there... more BACKGROUND: Although clonal origin is an essential step in the comprehension of neoplasias, there have been no studies to examine whether odontogenic tumours are derived from a single somatic progenitor cell. The purpose of this study was to investigate the clonal origin of odontogenic tumours. METHODS: Fresh samples of seven ameloblastomas, two odontogenic mixomas, two adenomatoid odontogenic tumour, one calcifying odontogenic cyst, one calcifying epithelial odontogenic tumour (CEOT) and six odontogenic keratocyst (OKC) of female patients were included in this study. After DNA extraction, the HUMARA gene polymorphism assay was performed. RESULTS: Most of the informative odontogenic lesions studied (12 out of 16) showed a monoclonal pattern. Among the polyclonal cases, two were OKC, one CEOT and one odontogenic mixoma. CONCLUSIONS: Our results suggest that most odontogenic tumours are monoclonal.
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