Expression of hypoxia-inducible factor-1 alpha is significantly associated with the progression and prognosis of oral squamous cell carcinomas in Taiwan.

Background: Overexpression of hypoxia-inducible factor-1 alpha (HIF-1 alpha) has been found to be significantly associated with the tumor invasion, lymph node metastasis, clinical stage, and prognosis of a variety of human cancers.

Methods: This study examined the expression of HIF-1 alpha in 57 specimens of oral squamous cell carcinoma (OSCC), 41 specimens of oral epithelial dysplasia (OED, 12 mild, 17 moderate, and 12 severe OED cases), and 14 specimens of normal oral mucosa (NOM) by immunohistochemistry.

Results: We found that the mean nuclear HIF-1 alpha labeling indices (LIs) increased significantly from NOM (9 +/- 6%) through mild OED (25 +/- 18%), moderate OED (41 +/- 27%), and severe OED (42 +/- 22%) to OSCC samples (55 +/- 23%, P < 0.

Levamisole can modulate the serum tumor necrosis factor-alpha level in patients with recurrent aphthous ulcerations.

Background: Recurrent aphthous ulcerations (RAU) are common oral inflammatory lesions. Tumor necrosis factor (TNF)-alpha is an important inflammatory mediator and a critical cytokine for adequate host defense. Our previous studies have shown that 14-43% and 59-63% of patients in the ulcerative stage of major, minor or herpetiform RAU have significantly higher than normal serum levels of interleukin (IL)-6 and IL-8, respectively.

HMB-45 may be a more sensitive maker than S-100 or Melan-A for immunohistochemical diagnosis of primary oral and nasal mucosal melanomas.

Background: Primary mucosal melanomas (MMs) of the head and neck are a rare entity. Melanomas with characteristic melanin-pigmented tumor cells are easy to diagnose, but those without melanin-pigmented tumor cells, amelanotic melanomas, are difficult to identify and need immunohistochemistry (IHC) to confirm the final diagnosis. In this study, we examined the expression of three melanocytic differentiation markers, HMB-45, S-100, and Melan-A in primary oral and nasal MMs.

Expression of hepatocyte growth factor and c-met protein is significantly associated with the progression of oral squamous cell carcinoma in Taiwan.

Background: Hepatocyte growth factor (HGF) is a pleotropic growth factor that regulates cell proliferation, migration, survival, tumor angiogenesis, and tumor cell invasion and metastasis. Its diverse biological effects are mediated through its interaction with its receptor, c-met protein.

Methods: In this study, we examined the expression of HGF and c-met protein in 93 specimens of oral squamous cell carcinoma (OSCC), 10 specimens of oral epithelial dysplasia (OED), 14 specimens of oral epithelial hyperkeratosis (OEH), and 16 specimens of normal oral mucosa (NOM) by immunohistochemistry.

Odontoma: a clinicopathologic study of 81 cases.

Background And Purpose: Odontoma is the most common odontogenic tumor. It includes 2 types, the compound and complex odontomas. There has not been a series study of the clinical and histologic features of odontomas from Taiwan.

Characteristics of calcifying odontogenic cyst in Taiwanese.

Background And Purpose: Calcifying odontogenic cyst (COC) is a rare type of odontogenic cyst. This retrospective study analyzed the clinical, radiographic, and histopathologic features of COC in Taiwanese.

Methods: Ten cases of COC in 2 male and 8 female patients with a mean age of 29 years (range, 11 to 48 years) treated from January 1985 to December 2002 were included.

Sequential expressions of MMP-1, TIMP-1, IL-6, and COX-2 genes in induced periapical lesions in rats.

To elucidate the pathogenesis of periapical lesion-associated bone resorption, a disease model of Wistar rat molar was employed. After lesion induction, the mRNAs encoding for matrix metalloproteinase-1 (MMP-1), tissue inhibitor of metalloproteinase-1 (TIMP-1), interleukin-6 (IL-6), and cyclooxygenase-2 (COX-2) in the developing lesions were detected by in situ hybridization at day 5, 10, 15 and 20, respectively. At day 5, MMP-1, IL-6 and COX-2 mRNAs appeared predominantly in macrophages.

Estrogen blocks parathyroid hormone-stimulated osteoclast-like cell formation in modulating differentiation of mouse marrow stromal cells in vitro.

Background And Purpose: During skeletal development and bone remodeling, bone marrow stromal cells give rise to osteoblasts and provide a critical microenvironment to support osteoclast formation. Estrogen is important for the maintenance of bone balance in adult animals by either increasing bone mass or inhibiting osteoclastic bone resorption. This study sought to determine the role that estrogen plays in coordinating osteogenic differentiation of bone marrow stromal cells and the ability of these cells to support osteoclast formation.

Estrogen inhibition of PTH-stimulated osteoclast formation and attachment in vitro: involvement of both PKA and PKC.

Estrogens modulate the catabolic effects of PTH on bone in vivo and in vitro. PTH-stimulated cAMP accumulation in osteoblasts is thought to be linked to increased osteoclastic activity, but the precise mechanism is still unknown. In cocultures of clonal marrow stromal cells (MS1) and normal mouse spleen cells, both 1,25-dihydroxyvitamin D3 and rat PTH (rPTH)-(1-34) can induce the formation of tartrate-resistant acid phosphatase- and calcitonin receptor-positive multinucleated osteoclast-like cells, which can attach to dentine slices and produce resorption pits.