Beta-6 Integrin, tenascin-C, and MMP-1 expression in salivary gland neoplasms.

Beta-6 Integrin, tenascin-C, and MMP-1 (matrix metalloproteinase-1) are invasion-related proteins that are frequently overexpressed in many human malignancies. The objective of this study was to determine whether there is overexpression of these molecules in three types of salivary neoplasms showing markedly different behavior. A total of 55 formalin-fixed, paraffin-embedded archived specimens comprising 19 adenoid cystic carcinomas (ACC), 18 polymorphous low-grade adenocarcinomas (PLGA) and 18 pleomorphic adenomas (PA) were utilized in this study.

Assessment of p63 expression in oral squamous cell carcinomas and dysplasias.

Objectives: p63, a p53 homologue, may be associated with tumorigenesis in epithelial tissues through its inhibition of p53 transactivation functions. We sought to determine the pattern and levels of p63 expression in oral dysplasias and carcinomas using standard immunohistochemical staining. We also assessed and compared expression of p53 and a cell proliferation marker in these lesions.

The expression of apoptotic proteins and matrix metalloproteinases in odontogenic myxomas.

Purpose: The odontogenic myxoma is a rare benign tumor affecting the jaws. We hypothesize that odontogenic myxomas have dysregulated antiapoptotic mechanisms to assist in neoplastic growth. We believe that antiapoptotic proteins of the Bcl-2 family are over expressed and that tumor cells must generate some form of matrix proteinase.

Oral spindle cell neoplasms: a review of 307 cases.

The infrequent exposure of pathologists to soft tissue spindle cell neoplasms coupled with overlapping histologic patterns can often make diagnosis challenging. We reviewed all nonodontogenic spindle cell neoplasms seen between 1982 and 2002 (86,162 total accessions). Diagnoses were reclassified according to current standards supplemented with immunohistochemistry.

Oral mucosal carcinogenesis in SENCAR mice.

Animal models of oral carcinogenesis have been developed but most use the hamster buccal pouch or rat oral mucosa. With completion of human and murine genome sequencing, the development of a mouse model of oral carcinogenesis may prove useful for future genomic studies of oral carcinogenesis. To achieve this objective, 30 SENCAR mice were initiated by brush application of palatal, buccal and tongue mucosa with 200 nmol 7,12-dimethylbenz[a]anthracene (DMBA) using 3 treatment regimens, and promoted by brush application with 5 nmol 12-O-tetradecanoylphorbol-13-acetate (TPA) for a total of 28 weeks.

Proliferation and invasion factors in HIV-associated dysplastic and nondysplastic oral warts and in oral squamous cell carcinoma: an immunohistochemical and RT-PCR evaluation.

Objective: Oral warts arising in human immunodeficiency virus (HIV) infection occasionally show marked epithelial dysplasia. However, anecdotal evidence suggests that they do not progress to oral squamous cell carcinoma (SCC). Therefore, we evaluated lesions for expression of proteins (tenascin-C, beta6 integrin, and matrix metalloproteinase-1[MMP1]) that have been identified as important in the invasive phase of oral SCC.

Oral lesions as the first clinical sign of microscopic polyangiitis: a case report.

Microscopic polyangiitis (MPA) is defined as a systemic necrotizing vasculitis that clinically and histologically affects small-sized vessels without granulomata. The main clinical feature of MPA is renal involvement characterized by rapidly progressing glomerulonephritis. We report a case of oral lesions, initially thought to be associated with Wegener's granulomatosis, as the first sign of MPA in an otherwise healthy man.

Effect of duration of fixation on quantitative reverse transcription polymerase chain reaction analyses.

Increasingly, there is the need to analyze gene expression in tumor tissues and correlate these findings with clinical outcome. Because there are few tissue banks containing enough frozen material suitable for large-scale genetic analyses, methods to isolate and quantify messenger RNA (mRNA) from formalin-fixed, paraffin-embedded tissue sections are needed. Recovery of RNA from routinely processed biopsies and quantification by the polymerase chain reaction (PCR) has been reported; however, the effects of formalin fixation have not been well studied.

Tenascin and beta 6 integrin are overexpressed in floor of mouth in situ carcinomas and invasive squamous cell carcinomas.

Floor of the mouth squamous cell carcinomas exhibit many characteristics that suggest they represent a distinct biological subset within head and neck tumors. The features of preinvasive lateral intraepithelial spread, high rate of conversion of intraepithelial neoplasia to invasive carcinoma, and high incidence of occult metastases, suggest the importance of motility-associated proteins in the pathogenesis of these lesions. Two such proteins, tenascin and beta 6 integrin, are generally overexpressed in squamous carcinomas, and may play a central role in the invasive process of floor of the mouth lesions.

Odontogenic cysts, odontogenic tumors, fibroosseous, and giant cell lesions of the jaws.

Odontogenic cysts that can be problematic because of recurrence and/or aggressive growth include odontogenic keratocyst (OKC), calcifying odontogenic cyst, and the recently described glandular odontogenic cyst. The OKC has significant growth capacity and recurrence potential and is occasionally indicative of the nevoid basal cell carcinoma syndrome. There is also an orthokeratinized variant, the orthokeratinized odontogenic cyst, which is less aggressive and is not syndrome associated.

Advanced diagnostic methods in oral and maxillofacial pathology. Part II: immunohistochemical and immunofluorescent methods.

The practice of pathology is currently undergoing significant change, in large part due to advances in the analysis of DNA, RNA, and proteins in tissues. These advances have permitted improved biologic insights into many developmental, inflammatory, metabolic, infectious, and neoplastic diseases. Moreover, molecular analysis has also led to improvements in the accuracy of disease diagnosis and classification.