The key mechanism for acetaminophen hepatotoxicity is cytochrome P450 (CYP)-dependent formation of N-acetyl-p-benzoquinone imine, a potent electrophile that forms protein adducts. Previous studies revealed the fundamental role of glutathione, which binds to and detoxifies N-acetyl-p-benzoquinone imine. Glutathione is synthesized from cysteine in the liver, and N-acetylcysteine is used as a sole antidote for acetaminophen poisoning.
View Article and Find Full Text PDFFor the doctors and other medical staff treating oral cancers, it is necessary to standardize basic concepts and rules on oral cancers to progress in the treatment, research and diagnosis. Oral cancers are integrated in head and neck cancers and are applied to the general rules on head and neck cancer, but it is considered that more detailed rules based on the characteristics of oral cancers are essential. The objectives of this 'General Rules for Clinical and Pathological Studies on Oral Cancer' are to contribute to the development of the diagnosis, treatment and research of oral cancers based on the correct and useful medical information of clinical, surgical, pathological and image findings accumulated from individual patients at various institutions.
View Article and Find Full Text PDFOral carcinogenesis is a complex process involving multiple genes. However, the genetic changes involved in this process are not apparent in identical oral squamous cell carcinomas (OSCCs). According to pathological characteristics, samples of normal tissue, oral dysplastic lesions (ODLs), and invasive cancers were obtained from identical OSCCs using laser microdissection (LMD).
View Article and Find Full Text PDFKokubyo Gakkai Zasshi
March 2012
Calcifying cystic odontogenic tumors are benign tumors, characterized by the presence of ghost cells and calcified materials. We evaluated clinical characteristics of calcifying cystic odontogenic tumors in 21 cases at the Maxillofacial Surgery, Tokyo Medical and Dental University Hospital, between January 1979 and December 2006. Of the 21 lesions that were studied, 12 were observed in male patients, and 9 in female patients.
View Article and Find Full Text PDFThe prognosis of oral squamous cell carcinoma (OSCC) is significantly dependent on the existence of cervical lymph node metastasis (LNM), with the overall survival rate being much lower in patients with LNM. Primary causes and molecular mechanisms of LNM are still largely unclear. We hypothesized that factors related with cancer progress and/or prognosis in OSCC are revealed by genome-wide investigation of DNA copy number aberrations (CNAs).
View Article and Find Full Text PDFAlthough vascular invasion (VI) is recognized as an important predictor of lymph node metastasis and a significant prognostic factor in head and neck squamous cell carcinoma (HNSCC), there is currently no common definition for the pathological evaluation of VI status. We reviewed the medical records of 63 consecutive resected primary oral tongue SCCs (OTSCCs) without preoperative treatment between June 1999 and April 2008, and evaluated VI status by investigating lymphatic vessel invasion (LVI) and blood vessel invasion (BVI) by using immunohistochemistry (IHC) with monoclonal antibody D2-40 (D2-40) and Elastica van Gieson (EVG) staining, respectively. Subsequently, we analyzed their correlations with cervical lymph node metastasis and prognosis.
View Article and Find Full Text PDFAlthough epidermal growth factor receptor (EGFR) is particularly important in the pathogenesis of head and neck squamous cell carcinomas (HNSCCs), conflicting data have been reported on the correlation between EGFR copy number and survival and the association between EGFR copy number and protein expression. Anatomical site of the tumour in HNSCCs may likely contribute to the discordance of the above points as EGFR expression may differ between the sub-sites of HNSCCs. Thus, in this study, we focused on oral tongue squamous cell carcinomas (OTSCCs).
View Article and Find Full Text PDFCementoblastoma is an uncommon disease, representing only 1-8% of all odontogenic tumours. Furthermore, this tumour is especially uncommon in children, as only five cases have been reported in this age group. Here, we describe a case of cementoblastoma arising in the maxilla of an 8-year-old boy, that was treated with a partial maxillectomy.
View Article and Find Full Text PDFPurpose: The purpose of this study was to clarify the clinico-pathological findings of Warthin's tumors.
Subjects And Methods: Twenty cases of Warthin's tumors treated at our clinic during the past 22 years and their medical charts and imaging films were reviewed.
Results: Warthin's tumors occurred more frequently in middle-aged or elderly men than in women.
Aims: This study aimed to identify relevant keratin subtypes that may associate with the pathogenesis of oral epithelial neoplasms.
Methods And Results: Expression of all the keratin subtypes was examined by cDNA microarray analysis of 43 oral squamous cell carcinoma (OSCC) cases. Immunohistochemical expression of the major keratins was examined in 100 OSCC and oral epithelial dysplasia (OED) cases.
Keratocystic odontogenic tumor is a cystic lesion that behaves more aggressively than other jaw cysts. One of its characteristic histologic features is a parakeratinized uniform layer of lining epithelium. A jaw cyst lined with orthokeratinized epithelium is called an orthokeratinized odontogenic cyst.
View Article and Find Full Text PDFTo determine whether staining with iodine solution provides an efficient criterion for determining the area of resection for the lesions surrounding squamous cell carcinoma (SCC) and leukoplakia of the tongue, we determined the optimum density of iodine solution and staining procedure and analyzed the color of lightly stained lesions (LSLs) in relation to the histopathologic findings. Sixty-five patients with SCC or leukoplakia of the tongue were divided into two groups: lesions stained with 3% Lugol solution and restained with either 5% Lugol solution (n=38) or 10% iodine glycerin (n=27). Among the lesions stained with 5% Lugol solution, significant differences were found in all color values.
View Article and Find Full Text PDFβ-catenin plays an important role in the maintenance of cell adhesion and is a key component of the Wnt signaling pathway. However, little is known about its prognostic significance or its role in tumor progression in tongue squamous cell carcinoma (SCC). This study conducted an immunohistochemical analysis of the expression of β-catenin.
View Article and Find Full Text PDFOral Surg Oral Med Oral Pathol Oral Radiol Endod
December 2009
Oral Surg Oral Med Oral Pathol Oral Radiol Endod
May 2009
This report describes the histological and immunohistochemical characteristics of 3 cases of nerve sheath myxoma (NSM)/neurothekeoma arising in the oral cavity. Histopathologically, 3 distinct variants were observed based on the amount of myxoid matrix: classic/hypocellular, cellular, and mixed types. Immunohistochemically, all types expressed strong immunoreactivity to S-100 protein (3/3), NSE (neuron-specific enolase) (3/3), and NGFR (nerve growth factor receptor) (3/3), whereas all cases were negative for SMA (smooth muscle actin) and FVIII.
View Article and Find Full Text PDFOral Surg Oral Med Oral Pathol Oral Radiol Endod
April 2009
Basal cell adenocarcinoma arising from the minor salivary gland is extremely rare. We report a 76-year-old Japanese man with basal cell adenocarcinoma originating in the upper gingiva. He underwent subtotal maxillectomy combined with resection of the coronoid process, and reconstruction was performed using a rectus abdominis microvascular flap.
View Article and Find Full Text PDFPurpose: To evaluate the diagnostic accuracy of cone-beam CT in assessing mandibular invasion by lower gingival carcinoma and compare it with that of panoramic radiography.
Patients And Methods: Fifty patients with squamous cell carcinoma of the lower gingiva who were examined by both panoramic radiography and cone-beam CT before surgery were included in this study. Five radiologists used a 6-point rating scale to independently evaluate cone-beam CT and panoramic images for the presence or absence of alveolar bone and mandibular canal involvement by tumor.
Desmocollin 3 (Dsc3) and desmoglein 3 (Dsg3) are both transmembrane glycoproteins that belong to the cadherin family of calcium-dependent cell adhesion molecules. beta-Catenin is a member of the cadherin-catenin complex that mediates homotypic cell-cell adhesion and is also an important molecule in the wnt signaling pathway. In this study, we examined the simultaneous expression level of Dsc3, Dsg3, and beta-catenin in oral squamous cell carcinomas (OSCCs) and normal oral epithelia using immunohistochemistry.
View Article and Find Full Text PDFOral Surg Oral Med Oral Pathol Oral Radiol Endod
May 2007
Purpose: We encountered a case of lipofibromatosis in a 21-month-old male patient and examined its histopathologic properties.
Methods: We examined morphological aspects of the tumor and immunohistochemical patterns.
Results: Tumor proliferation was infiltrative, which did not show apparent encapsulation.
Basal cell adenocarcinomas (BCACs) of the oral minor salivary gland are very rare neoplasms. We report on an 86-year-old woman with BCAC arising from the minor salivary gland in the soft palate. Histologically, the tumor was located in the submucosa and showed microinvasion into the adjacent soft tissue without encapsulation.
View Article and Find Full Text PDFWe report an immunohistochemical investigation of the expression of activated extracellular signal-regulated kinase (ERK1/2) and cyclin D1 protein in both oral tongue squamous cell carcinomas (OTSCCs) and normal tongue epithelium. The expression of Ki-67 labeling index (LI) was also examined in order to evaluate cell proliferation activity. The expression of activated ERK1/2, cyclin D1 protein and Ki-67 LI were significantly stronger in OTSCCs than in normal oral mucosa (P<0.
View Article and Find Full Text PDFSalivary gland acinic cell carcinoma (ACC) is a relatively rare neoplasm, and limited information is available regarding its molecular pathogenesis. Because the deregulation of Rb pathway is common to most human tumors, we immunohistochemically investigated the expression of Rb pathway-related proteins, including Rb, Rb proteins phosphorylated at serine 780 and 795 (pRb-S780 and pRb-S795, respectively), cyclin D1, and p16INK4a in 18 cases of ACC. The expression of topoisomerase II-alpha and Ki-67 was also examined to evaluate cell proliferation.
View Article and Find Full Text PDFThe purpose of the present study was to investigate the level of apoptosis and expressions of p53, mdm2 and bcl-2 proteins in salivary gland adenoid cystic carcinoma (ACC) to determine potential relationships among apoptosis, apoptosis-associated proteins and clinical cumulative survival. Thirty-nine formalin-fixed, paraffin-embedded cases, cribriform (17), tubular (13) and solid (9), were studied by immunohistochemistry. Apoptosis detection and analysis were determined by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL).
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